Soil Fertility and Plant Nutrition for Sustainable Agriculture

Journal Name	Impact Factor	CiteScore	Launched Year	First Decision (median)	APC
Horticulturae horticulturae	3.1	2.4	2015	14.7 Days	CHF 2200
Plants plants	4.5	5.4	2012	15.3 Days	CHF 2700
Agronomy agronomy	3.7	5.2	2011	15.8 Days	CHF 2600
Agriculture agriculture	3.6	3.6	2011	17.7 Days	CHF 2600
Sustainability sustainability	3.9	5.8	2009	18.8 Days	CHF 2400

15 pages, 4895 KiB

Open AccessArticle

Effect of Phosphorus Application on Subcellular Distribution and Chemical Morphology of Cadmium in Eggplant Seedlings under Cadmium Stress

by Qinghui Meng, Wenhua Fan, Fenwu Liu, Gailing Wang and Xiaoying Di

Agronomy 2024, 14(5), 932; https://doi.org/10.3390/agronomy14050932 - 29 Apr 2024

Viewed by 268

Abstract

Soil cadmium (Cd) contamination poses a serious threat to ecosystems, and the application of phosphorus fertilizers can reduce Cd toxicity. However, the specific effects of different phosphorus fertilizers on the subcellular distribution and chemical morphology of Cd in eggplant grown in calcareous Cd-contaminated [...] Read more.

Soil cadmium (Cd) contamination poses a serious threat to ecosystems, and the application of phosphorus fertilizers can reduce Cd toxicity. However, the specific effects of different phosphorus fertilizers on the subcellular distribution and chemical morphology of Cd in eggplant grown in calcareous Cd-contaminated soil remain unclear. This study examined the impact of various types and levels of phosphate fertilizers on the subcellular distribution and chemical morphology of cadmium in eggplant seedlings using a two-factor analysis. The investigation was conducted via a pot experiment utilizing a two-factor analysis. The application of 0.35 g kg⁻¹ dicalcium phosphate significantly decreased the Cd content in the subcellular distribution and induced notable alterations in the chemical morphology of Cd in eggplant roots. Specifically, the ethanol-extracted Cd state decreased by 65.45%, and the sodium chloride-extracted Cd state decreased by 64.65%. Conversely, Cd extracted by deionized water, acetic acid, hydrochloric acid, and the residue state increased by 6.20%, 4.01%, 20.87%, and 17.85%, respectively. The application of 0.35 g kg⁻¹ dicalcium phosphate resulted in the most significant reduction in Cd content in eggplant and modification of subcellular Cd distribution and chemical morphology in roots. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2034 KiB

Open AccessArticle

A Study of the Relationship between Initial Grape Yield and Soil Properties Based on Organic Fertilization

by Yuxia Wu, Zhengcheng Luo, Liang Qi, Rui Zhang and Yanxiu Wang

Agronomy 2024, 14(4), 861; https://doi.org/10.3390/agronomy14040861 - 20 Apr 2024

Viewed by 330

Abstract

Increasing the use of organic fertilizers is an effective measure to improve, increase soil fertility and maintain crop yields. The aim of this study was to investigate the influence of different types of organic fertilizers on the early yield of grapes and soil [...] Read more.

Increasing the use of organic fertilizers is an effective measure to improve, increase soil fertility and maintain crop yields. The aim of this study was to investigate the influence of different types of organic fertilizers on the early yield of grapes and soil parameters, as well as the relationship between soil parameters and grape yield under fertilization conditions. The ‘Shine Muscat’ grape was used as the material, with early maturing cultivation in the solar greenhouse. From the time of grape planting, three-year continuous fertilization management was carried out using five types of base fertilizers: chemical fertilizer (CK), fermented corn stalk residue (A1), mature sheep manure (A2) and two types of commercial organic fertilizers (B1 and B2). In the third year, berry and soil samples were collected to determine grape yield and evaluate soil physicochemical properties, nutrient status and changes in enzyme activity, studying the relationship between grape yield and soil indicators. The results show that compared to CK, the grape yields with B1 and B2 increased by 19.04% and 16.26%, respectively, while A1 and A2 decreased by 24.09% and 18.97%. Organic fertilizer application reduced soil bulk density, increased soil porosity, enhanced soil organic matter content and effectively buffered soil pH levels. Two types of commercial fertilizers (B1 and B2) improved soil total nitrogen, total phosphorus, total potassium, available nitrogen and available phosphorus content to varying degrees. All organic fertilizer treatments effectively increased soil enzyme activity, except for soil sucrase activity. Through correlation and regression analyses, it was found that in this study, the levels of available nitrogen, available potassium and soil saccharase activity were most closely related to early grape yield. Their influence on grape yield was in the order of available nitrogen > soil saccharase activity > available potassium. Therefore, with a combined organic and inorganic basal fertilization system, the fertilizer nutrients are more comprehensive and help to increase the productivity of grapes at the beginning of the fruiting period. Nitrogen and phosphorus are very important in the maintaining of grape yields and improving sucrose activity in the soil through the application of organic fertilizers cannot be ignored when increasing yields. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 3135 KiB

Open AccessArticle

The Influence of Different, Long-Term Fertilizations on the Chemical and Spectroscopic Properties of Soil Organic Matter

by Jerzy Weber, Lilla Mielnik, Peter Leinweber, Edyta Hewelke, Andrzej Kocowicz, Elżbieta Jamroz and Marek Podlasiński

Agronomy 2024, 14(4), 837; https://doi.org/10.3390/agronomy14040837 - 17 Apr 2024

Viewed by 334

Abstract

Currently, revealing soil management strategies that store the maximum atmospheric CO₂ in the soil is a major issue. This is best explored by investigating long-term experiments, like the Skierniewice (Poland) field trial, established in 1921 on sandy loam Luvisol. In this trial, [...] Read more.

Currently, revealing soil management strategies that store the maximum atmospheric CO₂ in the soil is a major issue. This is best explored by investigating long-term experiments, like the Skierniewice (Poland) field trial, established in 1921 on sandy loam Luvisol. In this trial, the variants analyzed included control (CON), manure (MAN), legumes (LEG), and manure + legumes (MAN + LEG). Soil samples from the A horizon were analyzed for total organic carbon (TOC), carbon content of humic acids (HA), fulvic acids (FA), and humin (HUM), as well as for spectroscopic properties of bulk soil and isolated HUM. Compared to the control, all other treatments caused an increase in TOC, while the application of manure resulted in an increase in the amount of HUM. Legume application caused an increase in UV-Vis absorbance and fluorescence emission. Thermochemolysis and gas chromatography/mass spectrometry showed that HUM was enriched in carbohydrates in almost all pairs of soil and HUM. Compared to the CON, the largest proportion of carbohydrate in HUM was found in MAN + LEG. Different long-term soil management strategies not only altered TOC, but also, surprisingly, the chemical composition of HUM, which is considered to be particularly stable and a long-term sink of atmospheric carbon. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1505 KiB

Open AccessArticle

Vegetable Response to Added Nitrogen and Phosphorus Using Machine Learning Decryption and the N/P Ratio

by Léon Etienne Parent

Horticulturae 2024, 10(4), 356; https://doi.org/10.3390/horticulturae10040356 - 03 Apr 2024

Viewed by 644

Abstract

The current N and P fertilization practices for vegetable crops grown in organic soils are inaccurate and and may potentially damage the environment. New fertilization models are needed. Machine learning (ML) methods can combine numerous features to predict crop response to N and [...] Read more.

The current N and P fertilization practices for vegetable crops grown in organic soils are inaccurate and and may potentially damage the environment. New fertilization models are needed. Machine learning (ML) methods can combine numerous features to predict crop response to N and P fertilization. Our objective was to evaluate machine learning predictions for marketable yields, N and P offtakes, and the N/P ratio of vegetable crops. We assembled 157 multi-environmental fertilizer trials on lettuce (Lactuca sativa), celery (Apium graveolens), onion (Allium cepa), and potato (Solanum tuberosum) and documented 22 easy-to-collect soil, managerial, and meteorological features. The random forest models returned moderate to substantial strength (R² = 0.73–0.80). Soil and managerial features were the most important. There was no response to added P and null to moderate response to added N in independent universality tests. The N and P offtakes were most impacted by P-related features, indicating N–P interactions. The N/P mass ratios of harvested products were generally lower than 10, suggesting P excess that would trigger plant N acquisition and possibly alter soil N and C cycles through microbial processes. Crop response prediction by ML models and ex post N/P ratio diagnosis and N and P offtakes proved to be useful tools to guide N and P management decisions in organic soils. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 2224 KiB

Open AccessArticle

Temporal Synchronization of Nitrogen and Sulfur Fertilization: Impacts on Nutrient Uptake, Use Efficiency, Productivity, and Relationships with Other Micronutrients in Soybean

by Azizullah Khalili, Ahlam Khalofah, Aketi Ramesh and Mahaveer P. Sharma

Agronomy 2024, 14(3), 570; https://doi.org/10.3390/agronomy14030570 - 12 Mar 2024

Viewed by 580

Abstract

Nitrogen (N) and sulfur (S) are essential nutrient elements, and their deficiency affects crop growth, productivity, and nutrient uptake due to their multifaceted role in plant metabolism, which has been well documented. Therefore, agricultural management strategies that can overcome these deficiencies are the [...] Read more.

Nitrogen (N) and sulfur (S) are essential nutrient elements, and their deficiency affects crop growth, productivity, and nutrient uptake due to their multifaceted role in plant metabolism, which has been well documented. Therefore, agricultural management strategies that can overcome these deficiencies are the need of the hour. In this context, a study was undertaken with the objective to assess the impacts of N and S applications, either basally or through split application (12.5, 25 and 50 kg ha⁻¹), on the nutrient uptake, productivity, use efficiency, and micronutrient content status in soybean seeds, and also the change in soil nutrient zinc (Zn) and iron (Fe) content at different critical stages of soybean crop growth. The field trial was conducted utilizing a randomized complete-block design, and comprised fourteen treatments with varying N and S quantities. N and S were applied through basal and split applications in different combinations. The salient findings indicated that the highest seed, straw yield, N, and S uptake were obtained with the application of N25+25, S25+25, and did not significantly vary with N25+25, S12.5+12.5, N50, and N25+S50. The highest N use efficiency was recorded with the application of N25+S50, and S use efficiency with the application of N25+25, S25+25. The split application of N and S as N25+25, S25+25 significantly increased soil Zn and Fe content at R₂ and R₅ stages of soybean crop growth, as well as seed Zn and Fe uptake. It can be concluded that the basal and split application of N and S at the rate of 25 kg ha⁻¹ can improve soybean productivity through increased mobilization and assimilation by plants. The findings indicated that applying N and S separately, with 25 kg ha⁻¹ each basally and at the R₂ stage resulted in the highest nutrient uptake, and seed and straw yields. The nutrient use efficiencies, along with Zn and Fe uptake by seeds, exhibited noticeable improvements with this split application approach compared to the control. Furthermore, the soil Zn and Fe contents also experienced enhancements due to the split application of both Nand S fertilizers. These results underscore the potential benefits of temporally adopting optimized fertilizer application strategies to maximize agricultural productivity while ensuring efficient nutrient utilization and soil health maintenance. Further research and field trials could provide deeper insights into the long-term impacts and scalability of this approach across different crop varieties and environmental conditions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 1437 KiB

Open AccessArticle

Assessment of Fertility Dynamics and Nutritional Quality of Potato Tubers in a Compost-Amended Mars Regolith Simulant

by Antonio Giandonato Caporale, Roberta Paradiso, Mario Palladino, Nafiou Arouna, Luana Izzo, Alberto Ritieni, Stefania De Pascale and Paola Adamo

Plants 2024, 13(5), 747; https://doi.org/10.3390/plants13050747 - 06 Mar 2024

Viewed by 620

Abstract

Mars exploration will foresee the design of bioregenerative life support systems (BLSSs), in which the use/recycle of in situ resources might allow the production of food crops. However, cultivation on the poorly-fertile Mars regolith will be very challenging. To pursue this goal, we [...] Read more.

Mars exploration will foresee the design of bioregenerative life support systems (BLSSs), in which the use/recycle of in situ resources might allow the production of food crops. However, cultivation on the poorly-fertile Mars regolith will be very challenging. To pursue this goal, we grew potato (Solanum tuberosum L.) plants on the MMS-1 Mojave Mars regolith simulant, pure (R100) and mixed with green compost at 30% (R70C30), in a pot in a cold glasshouse with fertigation. For comparison purposes, we also grew plants on a fluvial sand, pure (S100) and amended with 30% of compost (S70C30), a volcanic soil (VS) and a red soil (RS). We studied the fertility dynamics in the substrates over time and the tuber nutritional quality. We investigated nutrient bioavailability and fertility indicators in the substrates and the quality of potato tubers. Plants completed the life cycle on R100 and produced scarce but nutritious tubers, despite many critical simulant properties. The compost supply enhanced the MMS-1 chemical/physical fertility and determined a higher tuber yield of better nutritional quality. This study demonstrated that a compost-amended Mars simulant could be a proper substrate to produce food crops in BLSSs, enabling it to provide similar ecosystem services of the studied terrestrial soils. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2090 KiB

Open AccessArticle

Variation of Nitrogen, Phosphorus, and Potassium Contents in Drip-Irrigated Cotton at Different Yield Levels under Combined Effects of Nitrogen, Phosphorus and Potassium

by Yan Chen, Ming Wen, Xuehua Ma, Chenli Guo, Minghua Li, Wenqing Zhao, Yang Liu and Fuyu Ma

Agronomy 2024, 14(3), 503; https://doi.org/10.3390/agronomy14030503 - 29 Feb 2024

Viewed by 571

Abstract

To elucidate the variation characteristics of nitrogen (N), phosphorus (P), and potassium (K) content and accumulation in cotton at different yield levels, a two-year experiment was conducted using cotton variety Lumianyan 24 under four N treatments (506, 402.5, 299, and 195.5 kg ha [...] Read more.

To elucidate the variation characteristics of nitrogen (N), phosphorus (P), and potassium (K) content and accumulation in cotton at different yield levels, a two-year experiment was conducted using cotton variety Lumianyan 24 under four N treatments (506, 402.5, 299, and 195.5 kg ha⁻¹, designated as N1, N2, N3, and N4, respectively). The four P and K fertilization ratios were (PK-M1, 25% P and K applied at squaring stage (SS) and 75% at the bloom-bolling stages (BS)), 50%:50% (PK-M2, 50% P and K applied at each stage), 75%:25% (PK-M3, 75% P and K applied at SS and 25% at the BS) and 100%:0% (PK-M4, total P and K applied at SS). The results showed that the N content (Nc), P content (Pc), and K content (Kc) of cotton plants at high yield levels were 23.3%, 44.2%, and 31.6% higher than those at low yield levels. In addition, the reproductive organs maintained higher Pc and Kc at high yield levels, and the Nc, Pc, and Kc exhibited positive linear correlations with yield, while Nc/Pc, Nc/Kc, and Kc/Pc had significant negative correlations with yield. In conclusion, seed cotton yield was mainly limited by Nc at low yield levels and affected by Pc and Kc at high yield levels. Then, when 0.85 < Nc/Kc < 1.0 at the full squaring stage (FS), 0.8 < Nc/Kc < 1.0 at the full flowering stage (FF), 4.3 < Nc/Pc < 6.7 at the early-full bolling stage (EFB) and 4.9 < Nc/Pc < 7.1 at the late-full bolling stage (LFB), there is a high yield potential of 7000–9000 kg ha⁻¹. Furthermore, yields can be improved by reducing the application of N during the growing period and increasing the application of P fertilizer during the later growth period. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 1785 KiB

Open AccessArticle

Vegetation Restoration Increases Soil Carbon Storage in Land Disturbed by a Photovoltaic Power Station in Semi-Arid Regions of Northern China

by Wenjing Zhao, Jing Zhao, Meiying Liu, Yong Gao, Wenlong Li and Haiwen Duan

Agronomy 2024, 14(1), 9; https://doi.org/10.3390/agronomy14010009 - 20 Dec 2023

Viewed by 705

Abstract

The photovoltaic industry is developing rapidly because of its renewable energy and other advantages. However, the installation of this infrastructure may affect soil, vegetation, and carbon dynamics, making it is necessary to carry out vegetation restoration work at a plant’s location in the [...] Read more.

The photovoltaic industry is developing rapidly because of its renewable energy and other advantages. However, the installation of this infrastructure may affect soil, vegetation, and carbon dynamics, making it is necessary to carry out vegetation restoration work at a plant’s location in the later stages of its construction. For this reason, three types of artificial vegetation were selected (Pinus sylvestris var. mongolica, Astragalus membra-naceus var. mongholicus and Medicago sativa) as research objects in an ecological photovoltaic power plant in Northern China, to study the changes in soil organic carbon storage (SOCS), carbon:nitrogen ratios (C:N) and C:phosphorus ratios (C:P) at different soil depths and for different vegetation types. Natural vegetation plots undisturbed by the construction of the power plant were used as a control. Seven years after revegetation, we found that the storage and content of soil organic carbon in all three artificial vegetation plots were notably lower compared to the control. Nevertheless, the soil’s organic carbon content for Medicago sativa plots increased was significantly higher by 1.2 g·kg⁻¹ compared to Pinus sylvestris var. mongolica and A. membranaceus var. mongholicus plots, while organic carbon storage increased significantly by 3.55 t·ha and 7.15 t·ha. SOCS, C:N, and C:P concentrations in the 0–20 cm soil layer exhibited a significantly higher value in comparison to those of the 20–40 cm soil layer. As the soil depth increased, all the concentrations declined gradually. Vegetation type and soil depth, as well as their interaction, had a significant impact on soil carbon storage, C:N, and C:P. The study area was restricted by the availability of P. In general, vegetation restoration is a beneficial ecological practice for soil restoration at photovoltaic power stations. It is believed that planting alfalfa can accelerate the improvement of soil carbon with an extension of vegetation recovery time. In order to restore the balance of nutrients for plants, it is necessary to avoid human interference at the later stage, and to supplement phosphorus as soon as possible to minimize phosphorus limitation at the later stage of vegetation growth, which is of great importance to increasing the likelihood of success in reclaiming disturbed land. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 305 KiB

Open AccessArticle

The Effect of Long-Term Farmyard Manure and Mineral Fertilizer Application on the Increase in Soil Organic Matter Quality of Cambisols

by Jiří Balík, Pavel Suran, Ondřej Sedlář, Jindřich Černý, Martin Kulhánek, Simona Procházková, Dinkayehu Alamnie Asrade and Michaela Smatanová

Agronomy 2023, 13(12), 2960; https://doi.org/10.3390/agronomy13122960 - 30 Nov 2023

Viewed by 734

Abstract

Soil organic matter (SOM) quantity and quality are important factors that significantly influence soil fertility. SOM quality indicators change throughout time. In this study, long—term field experiments (22–50 years in duration) on a Cambisol at four sites in the Czech Republic were selected. [...] Read more.

Soil organic matter (SOM) quantity and quality are important factors that significantly influence soil fertility. SOM quality indicators change throughout time. In this study, long—term field experiments (22–50 years in duration) on a Cambisol at four sites in the Czech Republic were selected. Seven crops were successively rotated in the sequence: clover, winter wheat, early potato, winter wheat, spring barley, potato, and spring barley with interseeded clover. Five treatments were investigated, including an unfertilized treatment, farmyard manure, and various combinations of farmyard manure and mineral fertilization. A total of 40 t ha⁻¹ of farmyard manure was applied to the early potato and potato crops. Combining organic and mineral fertilizers increased soil organic matter quality and quantity over unfertilized or organic only treatment. The highest intensity of mineral fertilizers in our trials elevated the mean of carbon sequestration efficiency to 45.6% in comparison to pure manure treatment which reached only 22.9% efficiency. A strong correlation was established between the total glomalin content and soil organic matter carbon, fulvic acid, humic acid, carbon hot water extraction, potential wettability index (PWI), and aromaticity index. The PWI was also strongly correlated with these indicators. The E4/E6 ratio indicator was shown to be a much less sensitive method for reflecting the change in soil organic matter quality. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

14 pages, 3625 KiB

Open AccessArticle

Synergistic Effects of N Fertilization and Irrigation on Soil Bacterial Community in Super Rice Paddies

by Xiaoqing Qian, Jianing Huang, Ruqing Xie, Li Di, Juanjuan Wang and Guiliang Wang

Agronomy 2023, 13(12), 2856; https://doi.org/10.3390/agronomy13122856 - 21 Nov 2023

Viewed by 714

Abstract

Nitrogen reduction, in association with increased planting density and irrigation management, has been widely adopted in super rice cultivation systems to pursue higher yield with lower input. Here, soil microbial community structures under accurate N and water management were investigated after four years [...] Read more.

Nitrogen reduction, in association with increased planting density and irrigation management, has been widely adopted in super rice cultivation systems to pursue higher yield with lower input. Here, soil microbial community structures under accurate N and water management were investigated after four years of experiments. Plot experiments were conducted with three treatments, including conventional farming practice (CF), reduced nitrogen with increased plant density (RNID), and reduced nitrogen with increased plant density and precise irrigation (RNIDPI). The results showed that RNID treatment increased soil bacterial diversity, enriched biomarker bacterial taxa, and altered bacterial community structure, with pH as the influential factor. The phylum Chloroflexi was enriched in the treatment of N reduction, while a higher ratio of Firmicutes was present in CF treatments. RNID treatment witnessed a low proportion of bacterial functional groups involved in nitrification and nitrate reduction. N fertilizer reduction with irrigation management increased rice yield (up to 22%) without changing the major soil fertility properties except for the increased pH and decreased ammonium N. The results suggest that N reduction, in association with increased plant density and accurate irrigation, is beneficial for super rice production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 1474 KiB

Open AccessArticle

Exogenous Easily Extractable Glomalin-Related Soil Protein Induces Differential Response in Plant Growth of Tea Plants via Regulating Water Channel Protein Expression

by Xiao-Long Wu, Yong Hao, Feng-Jun Dai, Xin Chen and Chun-Yan Liu

Agronomy 2023, 13(11), 2797; https://doi.org/10.3390/agronomy13112797 - 12 Nov 2023

Viewed by 773

Abstract

Glomalin, a glycoprotein secreted by arbuscular mycorrhizal fungi (AMFs), exhibits multiple beneficial functions in regard to plant growth. However, the roles and regulatory mechanisms of exogenous easily extractable glomalin-related soil protein (EE-GRSP) in water and their effects on the quality of tea plants [...] Read more.

Glomalin, a glycoprotein secreted by arbuscular mycorrhizal fungi (AMFs), exhibits multiple beneficial functions in regard to plant growth. However, the roles and regulatory mechanisms of exogenous easily extractable glomalin-related soil protein (EE-GRSP) in water and their effects on the quality of tea plants (Camellia sinensis (L.) O. Ktze.) remain unclear. The present study aimed to investigate the effects of a quarter-strength exogenous EE-GRSP solution (1/4 EE-GRSP), half-strength exogenous EE-GRSP solution (1/2 EE-GRSP), three-quarter-strength exogenous EE-GRSP solution (3/4 EE-GRSP), and full-strength exogenous EE-GRSP solution (full EE-GRSP) on plant growth, the root system architecture, leaf water status, and the tea quality of tea seedlings, along with examining the changes in the relative expression of water channel proteins (AQPs) in tea plants. The results indicated that exogenous EE-GRSP of different strengths had different effects on both the growth performance (height, leaf numbers, and biomass) and root architecture parameters of tea seedlings, and the best positive effects on plant growth and the root architecture appeared under the three-quarter-strength exogenous EE-GRSP treatment. Similarly, the exogenous EE-GRSP application also differently affected tea quality indicators, in which only the quarter- and half-strength exogenous EE-GRSP solutions significantly increased most of the indicators, including carbohydrates, tea polyphenols, total amino acids, catechins, and flavonoids. Moreover, the half- and three-quarter-strength exogenous EE-GRSP treatments significantly increased the leaf relative water content (LRWC), but all of the exogenous EE-GRSP treatments significantly decreased the leaf water potential (LWP). Furthermore, the expression of AQP genes in the root system of tea plants was related to the strength of the exogenous EE-GRSP treatments, and different genes were significantly up-regulated or down-regulated under the treatment of exogenous EE-GRSP at different strengths. Moreover, the correlation analysis showed that most of the relative expression of AQPs was significantly and positively correlated with tea plant growth, the root architecture, and the leaf relative water content, but negatively correlated with tea quality indicators; however, the expression of CsNIPs and CsSIPs was markedly and negatively correlated with plant growth performance. Therefore, we speculated that the application of exogenous EE-GRSP could facilitate plant growth and improve the quality indirectly by regulating the expression of root AQPs, thus ameliorating the water uptake and nutrient accumulation in tea plants. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 3364 KiB

Open AccessArticle

Effect of Furrow Straw Mulching and Straw Decomposer Application on Celery (Apium graveolens L.) Production and Soil Improvement

by Zijian Zheng, Wangpei Zhou, Qianqian Yang, Jiezeng Jiang and Minmin Miao

Agronomy 2023, 13(11), 2774; https://doi.org/10.3390/agronomy13112774 - 06 Nov 2023

Viewed by 967

Abstract

Straw mulching on wet beds is an effective method to alleviate continuous cropping obstacles in greenhouses. However, this technique cannot be applied in the production of leafy vegetables with high planting density. Straw mulching in furrows is an alternative method in this circumstance. [...] Read more.

Straw mulching on wet beds is an effective method to alleviate continuous cropping obstacles in greenhouses. However, this technique cannot be applied in the production of leafy vegetables with high planting density. Straw mulching in furrows is an alternative method in this circumstance. In this study, celery (Apium graveolens L.), a vegetable that prefers a high planting density and wet soil, was used to test furrow straw mulching technology, and the effect of different straw amounts and straw decomposers on soil improvement and celery production was investigated. The results showed that straw mulching in furrows significantly reduced soil conductivity and nitrate nitrogen levels, increased the contents of soil organic carbon as well as phosphorus and potassium nutrients in the bed, and improved celery yield and quality, indicating the significant lateral movement of released nutrients between the furrow and bed. The positive effects of 15,000 kg/ha straw application were more pronounced than those of 7500 kg/ha and 11,250 kg/ha. In addition, straw decomposers accelerated nutrient release and improved celery yield and quality. A decomposer named “ZhuBang” containing Bacillus licheniformis was the most effective. We concluded that furrow straw mulching combined with straw decomposer application is an effective measure for the sustainable production of leafy vegetables in intensive vegetable production facilities. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 91234 KiB

Open AccessArticle

A Multicriteria Model for Estimating Coffea arabica L. Productive Potential Based on the Observation of Landscape Elements

by Jorge Eduardo F. Cunha, George Deroco Martins, Eusímio Felisbino Fraga Júnior, Silvana P. Camboim and João Vitor M. Bravo

Agriculture 2023, 13(11), 2083; https://doi.org/10.3390/agriculture13112083 - 01 Nov 2023

Viewed by 929

Abstract

Understanding a crop’s productive potential is crucial for optimizing resource use in agriculture, encouraging sustainable practices, and effectively planning planting and preservation efforts. Achieving precise and tailored management strategies is equally important. However, this task is particularly challenging in coffee cultivation due to [...] Read more.

Understanding a crop’s productive potential is crucial for optimizing resource use in agriculture, encouraging sustainable practices, and effectively planning planting and preservation efforts. Achieving precise and tailored management strategies is equally important. However, this task is particularly challenging in coffee cultivation due to the absence of accurate productivity maps for this crop. In this article, we created a multicriteria model to estimate the productive potential of coffee trees based on the observation of landscape elements that determine environmental fragility (EF). The model input parameters were slope and terrain shape data, slope flow power, and orbital image data (Landsat 8), allowing us to calculate the NDVI vegetation index. We applied the model developed to coffee trees planted in Bambuí, Minas Gerais, Brazil. We used seven plots to which we had access to yield data in a recent historical series. We compared the productivity levels predicted by the EF model and the historical productivity data of the coffee areas for the years 2016, 2018, and 2020. The model showed a high correlation between the calculated potential and the annual productivity. We noticed a strong correlation (R²) in the regression analyses conducted between the predicted productive potential and the actual productivity in 2018 and 2020 (0.91 and 0.93, respectively), although the correlation was somewhat weaker in 2016 (0.85). We conclude that our model could satisfactorily estimate the yearly production potential under a zero-harvest system in the study area. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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27 pages, 16433 KiB

Open AccessArticle

Spatial-Temporal Differentiation of Soil Biochemical Parameters and Their Relationship with Nitrogen Resources during the Vegetation Period of Selected Crops

by Agnieszka Wolna-Maruwka, Aleksandra Grzyb, Remigiusz Łukowiak, Jakub Ceglarek, Alicja Niewiadomska and Dariusz Kayzer

Agriculture 2023, 13(10), 2034; https://doi.org/10.3390/agriculture13102034 - 22 Oct 2023

Cited by 1 | Viewed by 1016

Abstract

Understanding the spatial–temporal variability of soil enzymatic activity and its relationship with nitrogen (N) resources in the soil and crop yield is crucial in rational management practices of mineral fertilization. The scarcity of comprehensive studies on geostatic analyses of agricultural soils and plant [...] Read more.

Understanding the spatial–temporal variability of soil enzymatic activity and its relationship with nitrogen (N) resources in the soil and crop yield is crucial in rational management practices of mineral fertilization. The scarcity of comprehensive studies on geostatic analyses of agricultural soils and plant yields, which would take into account both temporal and spatial variability, was the reason for undertaking this research. The aim of this study was to determine the spatial and temporal variability of the activity of soil enzymes, such as acid (PAC) and alkaline (PAL) phosphatases, urease (URE) and protease (PROT), the content of N-NH₄ (ammonium ions), N-NO₃ (nitrate ions), phosphorus (P), pH, moisture, as well as crop yield on a conventionally managed farmland of 40 ha. During the two-year experiment, soil samples were collected from 37 measurement points. Wheat was the first tested crop, followed by oilseed rape. It was shown that all the tested soil parameters showed temporal and spatial variability, and a significant number of them were significantly higher in July. The creation of raster maps showing the distribution of the tested parameters allowed for the observation of the considerable activity of PAC, PAL, URE, and PROT, as well as a high application of N-NO₃ in the southern part of the field during the growth of the plants. The statistical analysis revealed a negative interaction between the N-NH₄ and N-NO₃ and the urease in the soil under the cultivation of plants. The pH and the percentage of moisture in the soil also had higher values in the south of the field. This pointed to the existence of separate production zones in the south-central part of the field, characterized by a higher yield of wheat and rape. On the basis of the conducted research, it was unequivocally stated that the values of enzymatic and chemical parameters of the soil were reflected in the size of the yield obtained, which allows conclusions to be drawn with respect to the rational management of N in the production process, laying the foundations for precision agriculture. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 29302 KiB

Open AccessArticle

The Effects of Biochar-Based Organic Fertilizer and Mineral Fertilizer on Soil Quality, Beet Yield, and Sugar Yield

by Jingting Chen, Jian Li, Xiaofei Yang, Chao Wang, Linghua Zhao, Pengfei Zhang, He Zhang, Yubo Wang and Caifeng Li

Agronomy 2023, 13(9), 2423; https://doi.org/10.3390/agronomy13092423 - 20 Sep 2023

Cited by 1 | Viewed by 1214

Abstract

The addition of biochar-based organic fertilizer (BOF) can improve sugar beet yield, but its effects on the growth of sugar beet and on soil quality at different densities remain unclear. Six treatments, comprising two densities D1 and D2 (80,000 and 90,000 plant ha [...] Read more.

The addition of biochar-based organic fertilizer (BOF) can improve sugar beet yield, but its effects on the growth of sugar beet and on soil quality at different densities remain unclear. Six treatments, comprising two densities D1 and D2 (80,000 and 90,000 plant ha⁻¹) and three application rates B1, B2, and B3 (2.75, 3.25, and 3.75 t ha⁻¹) of BOFs + mineral fertilizer, respectively, are investigated in this research. The mineral fertilizers are typically used to supplement the total N, P₂O₅, and K₂O deficiencies. The BOFs were used in the soil before sowing, and the mineral fertilizer was added to the soil after the first pair of true leaves was grown. At 160 days after sowing (DAS), the root-to-shoot ratio under the D2B2 treatment was significantly higher than that under the other treatments. The effect of density on the photosynthesis rate of sugar beet was not significant. The BOF application amount and density exerted interaction effects on soil physicochemical properties and the activities of different soil enzymes affecting each other. Both the D2B2 and D2B3 treatments reduced the content of NO₃^–-N in the 40–60 cm soil layer. Combined 90,000 plants ha^–1 with 3.25 t ha⁻¹ BOFs can increase the soil nutrient content of the 0–60 cm soil layer, improve the rhizosphere soil environment, promote the uniform distribution of dry matter, and increase sugar production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 1567 KiB

Open AccessArticle

Effect of Pesticides and a Long-Life Inoculant on Nodulation Process and Soybean Seed Quality during Storage

by Rodrigo S. Araújo, Gisele C. Silva, Itamar R. Teixeira, Guilherme R. Silva, Bruna Mayara F. Souza, Ivano A. Devilla, Marcos Eduardo V. Araújo and Paulo C. Corrêa

Agronomy 2023, 13(9), 2322; https://doi.org/10.3390/agronomy13092322 - 05 Sep 2023

Viewed by 810

Abstract

Inoculants containing strains of bacteria that fix atmospheric N that are tolerant or resistant to chemical products commonly used in seed treatment are classified as long-life inoculants, which contribute to improving the efficiency of nodulating bacteria in soybean crops. The objective of this [...] Read more.

Inoculants containing strains of bacteria that fix atmospheric N that are tolerant or resistant to chemical products commonly used in seed treatment are classified as long-life inoculants, which contribute to improving the efficiency of nodulating bacteria in soybean crops. The objective of this work was to evaluate the effects of applying commonly used pesticides in seed treatment and a long-life inoculant, alone or in combination, on the nodulation process and seed quality of soybeans during storage. The first experiment was carried out in a greenhouse using a completely randomized design, in an 8 × 2 factorial arrangement, with three replications. The treatments consisted of applications of industrial seed treatments: control, MaximAdvanced, Fortenza, long-life inoculant, MaximAdvanced + Fortenza, MaximAdvanced + long-life inoculant, Fortenza + long-life inoculant, and MaximAdvanced + Fortenza + long-life inoculant. The seeds were sown in pots containing soils from two crop areas. The second experiment was carried out in a laboratory, using a completely randomized design in an 8 × 7 factorial arrangement, with four replications. The treatments consisted of the same eight treatments used in the greenhouse experiment, which were applied before packaging and storing the seeds for two months. The industrial seed treatment with the mixture of fungicide, insecticide, and inoculants improved the soybean photosynthesis and nodulation processes, regardless of the history of the area. Soybean seeds can be stored for commercial purposes for up to 40 days, regardless of the seed treatment with fungicide, insecticide, and long-life inoculant applied alone or in combination. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 1257 KiB

Open AccessArticle

The Efficacy of 5-Aminolevulinic Acid-Producing Luteovulum sphaeroides Strains on Saline Soil Fertility, Nutrient Uptakes, and Yield of Rice

by Nguyen Quoc Khuong, Nguyen Thi Thuy Dung, Le Thi My Thu, Le Thanh Quang, Ly Ngoc Thanh Xuan and Ngo Thanh Phong

Agriculture 2023, 13(9), 1761; https://doi.org/10.3390/agriculture13091761 - 05 Sep 2023

Viewed by 949

Abstract

Saline soils negatively affect and cause serious problems for rice cultivation. This study aimed to evaluate the efficacy of the purple nonsulfur bacteria (PNSB) capable of secreting 5-aminolevulinic acid (ALA) to reduce soil salinity, improve soil fertility, and enhance rice growth and yield. [...] Read more.

Saline soils negatively affect and cause serious problems for rice cultivation. This study aimed to evaluate the efficacy of the purple nonsulfur bacteria (PNSB) capable of secreting 5-aminolevulinic acid (ALA) to reduce soil salinity, improve soil fertility, and enhance rice growth and yield. A two-factorial experiment was conducted in a randomized complete block design with four replications. Factor one was the salinity of the irrigated water, and factor two was the supplementation of the ALA-producing PNSB. The results indicated that watering with saline water above 3‰ led to decreases in plant growth and rice yield compared to the treatments watered with tap water. Application of either an individual strain or the mixture of W01, W14, and W22 ameliorated soil properties and increased total NPK uptake, whereas treatments supplied with the mixed strains reduced total Na uptake (9.50 mg Na pot⁻¹). Supplying the W01, W14, and W22 strains individually or in a mixture enhanced the plant height by 3.51–5.45% and rice grain yield by 14.7–26.2%, compared with those of the control treatment. From the study, the combination of the L. sphaeroides W01, W14, and W22 strains is promising for application in saline or salt-contaminated regions to aid the damages caused by salinity on cultivars there, especially rice. Furthermore, this is a biological approach to ease an environmental problem and improve crop performance, which is supposed to be a trend in the sustainable agriculture. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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26 pages, 8724 KiB

Open AccessArticle

Enhancing Phosphorus and Nitrogen Uptake in Maize Crops with Food Industry Biosolids and Azotobacter nigricans

by Sara-Luz Vera-García, Felipe-Neri Rodríguez-Casasola, Josefina Barrera-Cortés, Arnulfo Albores-Medina, Karla M. Muñoz-Páez, Rosa-Olivia Cañizares-Villanueva and Ma.-Carmen Montes-Horcasitas

Plants 2023, 12(17), 3052; https://doi.org/10.3390/plants12173052 - 25 Aug 2023

Viewed by 1306

Abstract

The problem of phosphorus and nitrogen deficiency in agricultural soils has been solved by adding chemical fertilizers. However, their excessive use and their accumulation have only contributed to environmental contamination. Given the high content of nutrients in biosolids collected from a food industry [...] Read more.

The problem of phosphorus and nitrogen deficiency in agricultural soils has been solved by adding chemical fertilizers. However, their excessive use and their accumulation have only contributed to environmental contamination. Given the high content of nutrients in biosolids collected from a food industry waste treatment plant, their use as fertilizers was investigated in Zea mays plants grown in sandy loam soil collected from a semi-desert area. These biosolids contained insoluble phosphorus sources; therefore, given the ability of Azotobacter nigricans to solubilize phosphates, this strain was incorporated into the study. In vitro, the suitable conditions for the growth of Z. mays plants were determined by using biosolids as a fertilizer and A. nigricans as a plant-growth-promoting microorganism; in vitro, the ability of A. nigricans to solubilize phosphates, fix nitrogen, and produce indole acetic acid, a phytohormone that promotes root formation, was also evaluated. At the greenhouse stage, the Z. mays plants fertilized with biosolids at concentrations of 15 and 20% (v/w) and inoculated with A. nigricans favored the development of bending strength plants, which was observed on the increased stem diameter (>13.5% compared with the negative control and >7.4% compared with the positive control), as well as a better absorption of phosphorus and nitrogen, the concentration of which increased up to 62.8% when compared with that in the control treatments. The interactions between plants and A. nigricans were observed via scanning electron microscopy. The application of biosolids and A. nigricans in Z. mays plants grown in greenhouses presented better development than when Z. mays plants were treated with a chemical fertilizer. The enhanced plant growth was attributed to the increase in root surface area. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2160 KiB

Open AccessArticle

Swine Manure Reduces Nitrous Oxide Emissions from Acidic Red Soil Due to Mineral N Immobilization and Alleviated Acidification

by Lu Zhang, Tusheng Ren, Jiwen Li, Kiya Adare, Nano Alemu Daba, Md Ashraful Alam, Shilin Wen and Huimin Zhang

Agronomy 2023, 13(9), 2201; https://doi.org/10.3390/agronomy13092201 - 23 Aug 2023

Viewed by 854

Abstract

Swine manure is widely used for ameliorating red soil acidification, but little information is available about its effect on N₂O emissions. To explore the effects, a 35-day incubation experiment was conducted with two soils under different fertilization history: chemical fertilizers only [...] Read more.

Swine manure is widely used for ameliorating red soil acidification, but little information is available about its effect on N₂O emissions. To explore the effects, a 35-day incubation experiment was conducted with two soils under different fertilization history: chemical fertilizers only (F) and combination of chemical fertilizers with swine manure (M). The treatments included no fertilizer (control), 100% N from urea (M0), and urea plus swine manure, which supplied 20% (M20), 40% (M40), 60% (M60), and 100% (M100) of total N. Soil N₂O emission rates, pH, exchangeable acidity, mineral N species, dissolved organic carbon and nitrogen, microbial biomass carbon, and their inner relationships were examined. The N₂O emission rates markedly increased following the treatments, reached peaks before day 2, and thereafter decreased sharply to the level of the control by day 25, 25, 23, 15, and 9 in F soil and by day 25, 25, 23, 19, and 11 in M soil for M0, M20, M40, M60, and M100 treatments, respectively. As swine manure application rate increased, the cumulative N₂O emissions of F soil decreased significantly, while, for M soil, there was no significant difference among M0, M20, M40, and M60 treatments, which were higher than the M100 treatment. At the end of incubation, soil pH in F and M soils followed the order M0 < M20 < M40 < M60 < control < M100 and vice versa for exchangeable Al³⁺ and acidity. F soil had relatively higher NH₄⁺-N concentration in M0 treatment and higher NO₃⁻-N concentrations in M0 and M20 treatments than M soil. Soil pH and NH₄⁺-N had the greatest relative contribution to N₂O emissions. Overall, this study indicates that partial chemical N replacement by swine manure could effectively mitigate N₂O emissions from acidic red soil primarily because of mineral N immobilization and alleviated red soil acidification. Thus, swine manure has the potential to co-ameliorate red soil acidification and N₂O emission. Further research is needed to determine the effect of swine manure on N₂O emission reductions under field conditions and the overall benefit in effective N management. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 1906 KiB

Open AccessArticle

Fertilizers Containing Balanced Proportions of NH₄⁺-N and NO₃⁻-N Enhance Maize (Zea mays L.) Yield Due to Improved Nitrogen Recovery Efficiency

by Sajid Masood, Muhammad Suleman, Sajid Hussain, Muhammad Jamil, Muhammad Ashraf, Manzer H. Siddiqui, Rizwan Nazar, Naseerullah Khan, Sarvet Jehan, Khalid Saifullah Khan and Muhammad Tahir

Sustainability 2023, 15(16), 12547; https://doi.org/10.3390/su151612547 - 18 Aug 2023

Cited by 1 | Viewed by 891

Abstract

The current study aimed to improve the nitrogen recovery efficiency (NRE) of maize under the application of balanced proportions of ammoniacal-nitrogen (NH₄⁺-N) and nitrate-nitrogen (NO₃⁻-N) (1:1), as well as to determine economic impacts of such fertilizers on [...] Read more.

The current study aimed to improve the nitrogen recovery efficiency (NRE) of maize under the application of balanced proportions of ammoniacal-nitrogen (NH₄⁺-N) and nitrate-nitrogen (NO₃⁻-N) (1:1), as well as to determine economic impacts of such fertilizers on maize productivity. A 3-year field study was carried out in Sahiwal, Punjab, Pakistan during the 2018–2020 growing seasons with autumn maize. In parallel, multi-location field experiments were conducted at farmer’s fields in Sahiwal during the same growing seasons with autumn maize. The trials compared the effects of different fertilizers like urea, calcium ammonium nitrate (CAN), Sarsabz nitrophos (NP), nitrphos plus (NP Plus), and di-ammonium phosphate (DAP) on maize growth and yield, as well their economic efficiency. The results revealed that the application of Sarsabz NP and CAN increased the maize grain yield by 30%, 13%, 15%, 19%, 15%, and 9% as compared to the control, NP + urea, NP Plus + CAN, NP Plus + urea, DAP + urea, and DAP + CAN, respectively. In addition, the combined application of NP and CAN increased the total N and NO₃⁻-N concentrations, whereas it decreased the NH₄⁺-N concentrations in the soils. By contrast, NP + CAN increased the NH₄⁺-N concentrations in maize leaves as compared to NO₃⁻-N concentrations. Overall, the NRE of maize plants and the net return were higher under combined application of NP and CAN. In conclusion, CAN fertilizer increased the soil NO₃⁻-N concentrations, which thus assimilated in the plants as NH₄⁺ and improved the NRE of maize. Improved NRE thus enhanced maize yield and resulted in the maximum net return as compared to all other fertilizer combinations. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 1065 KiB

Open AccessArticle

Monitoring of Soil Nutrient Levels by an EC Sensor during Spring Onion (Allium fistulosum) Cultivation under Different Fertilizer Treatments

by Govind Dnyandev Vyavahare, Yejin Lee, Yeong Ju Seok, Han Na Kim, Jwakyung Sung and Jin Hee Park

Agronomy 2023, 13(8), 2156; https://doi.org/10.3390/agronomy13082156 - 17 Aug 2023

Cited by 2 | Viewed by 1712

Abstract

Balanced nutrients are essential for healthy plant growth, but there is no sensor available to monitor essential nutrients such as N and K. Electrical conductivity (EC) is one of the key parameters that could be adopted to monitor nutrient contents because soil EC [...] Read more.

Balanced nutrients are essential for healthy plant growth, but there is no sensor available to monitor essential nutrients such as N and K. Electrical conductivity (EC) is one of the key parameters that could be adopted to monitor nutrient contents because soil EC is influenced by the available nutrients. Therefore, the main objective of this study was to examine the effects of different basal fertilizers, including inorganic, organic, and compost fertilizers, and the application ratio of basal and additional fertilizers on nutrient contents with an EC sensor. The applied basal and additional fertilizer ratios were N 30:70, K 40:60, and N 20:80, K 20:80, respectively, for each fertilizer treatment. The results showed that the EC sensor value was positively associated with water content. The soil EC response increased with inorganic fertilizer and fertigation, and it was positively correlated with soluble nutrients and exchangeable ammonium. The correlation coefficients between sensor EC and soluble nutrients, nitrate, and ammonium nitrogen were 0.87, 0.86, and 0.65, respectively. The principal component analysis (PCA) also elucidated that inorganic fertilizer was positively associated with sensor EC, soluble Na, Ca, Mg, and nitrate among variables. This work suggests that soil available nutrients, especially N, could be monitored with an EC sensor, and the soil nutrient status could be regulated to promote better plant growth. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2726 KiB

Open AccessArticle

Impact of Sea Rice Planting on Enzymatic Activity and Microbial Community of Coastal Soils: Focus on Proteinase

by Jie Yang, Zhiyun Liu, Mingyi Zhang, Xiaolong Zhu, Mingyi Wang, Xingfeng Xu and Guangchao Liu

Agronomy 2023, 13(8), 2089; https://doi.org/10.3390/agronomy13082089 - 09 Aug 2023

Viewed by 867

Abstract

Soil proteinase and proteinase-producing microbial community are closely associated with soil fertility and soil health. Sea rice has been planted in the coastal beach of Jiaozhou Bay, China, in an effort to transform saline-alkali soil into arable land. However, the knowledge regarding the [...] Read more.

Soil proteinase and proteinase-producing microbial community are closely associated with soil fertility and soil health. Sea rice has been planted in the coastal beach of Jiaozhou Bay, China, in an effort to transform saline-alkali soil into arable land. However, the knowledge regarding the bacterial degradation of organic nitrogen in sea rice soils is limited. This study aims to investigate the physicochemical characteristics and enzymatic activities of the sea rice soils, as well as the microbial communities by both the Illumina sequencing-based culture-independent technology and culture-dependent methods. Sea rice soils exhibited a lower salinity and higher organic matter content and proteinase activity, as well as an increase in both the richness and diversity of the proteinase-producing bacterial community, compared to the adjacent non-rice soils. The Proteobacteria phylum and the Gammaproteobacteria class were dominant in sea rice soils, showing higher abundance than in the reference soils. The Planococcus genus and Bacillus-like bacterial communities were abundant in the cultivable proteinase-producing bacteria isolated from sea rice soils. Furthermore, a significant proportion of the extracellular proteinase produced by the isolated soil bacteria consisted of serine proteinases and metalloproteinases. These findings provided new insights into the degradation of soil organic nitrogen in coastal agricultural regions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 2916 KiB

Open AccessArticle

Effect of Potassium Application Rates on Sugarcane Yield in Soils with Different Non-Exchangeable Potassium Reserves and Fixation Capacity

by Dimpho Elvis Elephant, Neil Miles and Pardon Muchaonyerwa

Agronomy 2023, 13(8), 1969; https://doi.org/10.3390/agronomy13081969 - 26 Jul 2023

Viewed by 1136

Abstract

Reliable fertilizer recommendations should account for factors influencing nutrient supply, including non-exchangeable potassium (K) reserves and fixation capacity, to ensure optimum crop yields. The combined effects of non-exchangeable K reserves and fixation capacity of soils on crop response to K application has not [...] Read more.

Reliable fertilizer recommendations should account for factors influencing nutrient supply, including non-exchangeable potassium (K) reserves and fixation capacity, to ensure optimum crop yields. The combined effects of non-exchangeable K reserves and fixation capacity of soils on crop response to K application has not been evaluated. This study evaluated the response of sugarcane yields to K application on two soils with contrasting combinations of non-exchangeable K reserves and fixation capacity. Potassium was applied at 0, 120, and 240 kg K ha⁻¹ at the commencement of the field trials and after each harvest on an umbric Acrisol, which had low non-exchangeable K reserves and medium K fixation capacity, and a cutanic Acrisol, which had ‘very high’ non-exchangeable K reserves and fixation capacity. Sugarcane stalk and sucrose yield, leaf, and exchangeable K were measured for each season. In the umbric Acrisol, a lower sucrose yield was measured in the 240 kg K ha⁻¹ treatment compared to the control for the plant crop, but this application rate had higher yields for the second ratoon. In contrast, there was no yield response to K application in cutanic Acrisol. This study indicated the importance of non-exchangeable K reserves and fixation capacity when calculating K requirements and conducting field calibration studies. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 2538 KiB

Open AccessArticle

Grain Yield of Maize Crops under Nitrogen Fertigation Using Wastewater from Swine and Fish Farming

by Daniely Karen Matias Alves, Marconi Batista Teixeira, Fernando Nobre Cunha, Fernando Rodrigues Cabral Filho, Gabriela Nobre Cunha and Christiano Lima Lobo de Andrade

Agronomy 2023, 13(7), 1834; https://doi.org/10.3390/agronomy13071834 - 11 Jul 2023

Cited by 1 | Viewed by 1026

Abstract

Maize is one of the most important cereals in the world. It is a crop demanding in nitrogen. Therefore, alternative sources of fertilization bring agronomic, environmental and economic benefits. The objective of this study was to evaluate the biomass and productivity of maize [...] Read more.

Maize is one of the most important cereals in the world. It is a crop demanding in nitrogen. Therefore, alternative sources of fertilization bring agronomic, environmental and economic benefits. The objective of this study was to evaluate the biomass and productivity of maize fertigated with wastewater from swine and fish farming in different dilutions. The soil used is classified as Dystroferric Red Latosol, Cerrado phase, with clayey texture. The experimental design used was randomized blocks in 2 × 4 split plots with three replications. The treatments consisted of two sources of wastewater (fish farming and swine farming) diluted with the recommended dose of wastewater + 0, 25, 50 and 75% of its volume in water. The accumulation of dry mass (leaf, stalk and aerial parts) was evaluated at 30, 60, 90 and 110 days after sowing. The evaluation of yield variables (number of grain rows, number of grains per row, grain sizes, grain dry weight, gran yield and harvest index) occurred at 130 days after sowing. The largest accumulation of dry biomass at the end of the maize cycle and evaluated productivity variables were obtained with the application of swine farming wastewater. Wastewater from fish farming applied via an irrigation system without dilution (0%) is the most suitable for obtaining the productivity of corn grains. The two sources of wastewater have the potential to partially replace mineral nitrogen fertilizer in maize. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2691 KiB

Open AccessArticle

Combined Application of Arbuscular Mycorrhizal Fungi (AMF) and Nitrogen Fertilizer Alters the Physicochemical Soil Properties, Nitrogen Uptake, and Rice Yield in a Polybag Experiment

by Mulyadi and Ligeng Jiang

Agriculture 2023, 13(7), 1364; https://doi.org/10.3390/agriculture13071364 - 09 Jul 2023

Cited by 2 | Viewed by 1485

Abstract

Excessive application of nitrogen fertilizer during rice cultivation leads to progressive soil contamination in the long term and increases production costs. An alternative to reduce over fertilization is to partially replace the fertilizer with microbes that promote nutrition and growth, such as arbuscular [...] Read more.

Excessive application of nitrogen fertilizer during rice cultivation leads to progressive soil contamination in the long term and increases production costs. An alternative to reduce over fertilization is to partially replace the fertilizer with microbes that promote nutrition and growth, such as arbuscular mycorrhizal fungi (AMF). We investigated the combination of four different rates of AMF (M): (M₀: 0 g polybag⁻¹, M₁: 15 g polybag⁻¹, M₂: 30 g polybag⁻¹, and M₃: 45 g polybag⁻¹) and three rates of nitrogen (N) fertilizer: (N₀: 0 kg N ha⁻¹, N₁: 90 kg N ha⁻¹, N₂: 180 kg N ha⁻¹) on Trisakti rice cultivar cultivated in polybag. Our findings indicate that the combination of 45 g AMF polybag⁻¹ and 180 kg N ha⁻¹ decreased soil bulk density by 38.02% and 37.24%, increased soil pH by 14.81% and 14.95%, soil porosity by 60.68% and 61.09%, soil organic matter by 28.62% and 30.46%, total N by 92.59% and 89.66%, available phosphorus by 30.12% and 29.85%, available potassium by 3.75% and 4.01%, rice plant height by 19.19% and 19.79%, tiller number by 25.27% and 26.08%, SPAD by 20.71% and 20.62%, flag leaf area by 107.76% and 108.02%, panicle length by 49.72% and 52.31%, panicle number by 67.44% and 72.35%, 1000-grain weight by 30.70% and 32.44%, root dry matter by 54.34% and 53.69%, shoot dry matter by 26.08% and 28.26%, root length by 54.68% and 56.44%, root volume by 42.73% and 43.37%, and N uptake by 107.93% and 108.06% compared to control during the early and late seasons, respectively. Conclusively, the combined application of AMF and N fertilizer increased the physiochemical properties, rice growth, rice productivity, and N uptake compared to AMF alone, N fertilizer alone, and the control treatment. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 970 KiB

Open AccessArticle

Physiological and Histological Characterization of the ESB1 TILLING Mutant of Brassica rapa L.: Potential Use in Biofortification and Phytoremediation Programs

by Santiago Atero-Calvo, Juan José Rios, Eloy Navarro-León, Juan M. Ruiz and Begoña Blasco

Agronomy 2023, 13(6), 1642; https://doi.org/10.3390/agronomy13061642 - 19 Jun 2023

Viewed by 1080

Abstract

Enhanced suberin1 (ESB1) is a protein whose mutation is correlated with an increase in root suberin and altered nutrient concentrations. Here, we show a physiological and histological characterization of esb1 mutant plants of Brassica rapa L. Therefore, the potential use of this mutant [...] Read more.

Enhanced suberin1 (ESB1) is a protein whose mutation is correlated with an increase in root suberin and altered nutrient concentrations. Here, we show a physiological and histological characterization of esb1 mutant plants of Brassica rapa L. Therefore, the potential use of this mutant in selenium (Se) biofortification and/or cadmium (Cd) phytoremediation programs was also evaluated by applying 20 μM of Na₂SeO₄ and 0.49 μM of CdCl₂ to a nutrient solution. With respect to wild type (WT) plants, an increase in root suberin was observed in esb1 at the level of the exodermis. This increase in root suberin did not affect photosynthesis performance. However, the esb1 mutant showed an increase in transpiration rate and a decrease in water use efficiency. Additionally, root histological changes affected the transport and concentration of some mineral elements. Thus, our results suggest that esb1 mutants of B. rapa would not be useful for Se biofortification because no significant differences were observed between the two genotypes at the leaf level. Nevertheless, the esb1 mutant reduced Cd translocation to the leaves and increased Fe and Cu uptake, so ESB1 mutation could be useful for Cd phytoremediation and Fe and Cu biofortification, although further research is needed. Therefore, this study provides detailed information on the effect of ESB1 mutation in B. rapa and suggests its potential use in biofortification and phytoremediation programs. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 5867 KiB

Open AccessEditor’s ChoiceArticle

Research and Design of Hybrid Optimized Backpropagation (BP) Neural Network PID Algorithm for Integrated Water and Fertilizer Precision Fertilization Control System for Field Crops

by Fenglei Zhu, Lixin Zhang, Xue Hu, Jiawei Zhao, Zihao Meng and Yu Zheng

Agronomy 2023, 13(5), 1423; https://doi.org/10.3390/agronomy13051423 - 21 May 2023

Cited by 11 | Viewed by 1840

Abstract

China’s field crops such as cotton, wheat, and tomato have been produced on a large scale, but their cultivation process still adopts more traditional manual fertilization methods, which makes the use of chemical fertilizers in China high and causes waste of fertilizer resources [...] Read more.

China’s field crops such as cotton, wheat, and tomato have been produced on a large scale, but their cultivation process still adopts more traditional manual fertilization methods, which makes the use of chemical fertilizers in China high and causes waste of fertilizer resources and ecological environmental damage. To address the above problems, a hybrid optimization of genetic algorithms and particle swarm optimization (GA–PSO) is used to optimize the initial weights of the backpropagation (BP) neural network, and a hybrid optimization-based BP neural network PID controller is designed to realize the accurate control of fertilizer flow in the integrated water and fertilizer precision fertilization control system for field crops. At the same time, the STM32 microcontroller-based precision fertilizer application control system for integrated water and fertilizer application of large field crops was developed and the performance of the controller was verified experimentally. The results show that the controller has an average maximum overshoot of 5.1% and an average adjustment time of 68.99 s, which is better than the PID and PID control algorithms based on BP neural network (BP–PID) controllers; among them, the hybrid optimization of PID control algorithm based on BP neural network by particle swarm optimization and genetic algorithm(GA–PSO–BP–PID) controller has the best-integrated control performance when the fertilizer application flow rate is 0.6m³/h. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 2183 KiB

Open AccessArticle

Effect of Drip Irrigation, N, K, and Zn Coupling on

P n

of Densely Cultivated Apple on Dwarf Rootstock in Xinjiang, China

by Weiyi Mu, Xiaoxian Duan, Quanjiu Wang, Xuesong Wei, Kai Wei, Yuanxin Li and Xin Guo

Agronomy 2023, 13(4), 1082; https://doi.org/10.3390/agronomy13041082 - 09 Apr 2023

Cited by 2 | Viewed by 1272

Abstract

This study aimed to determine the effect of irrigation amount (

W

), nitrogen (

N

), potassium (

K

), and zinc (

Z n

) on the net photosynthetic rate (

P n

) of closely planted apple trees on dwarf [...] Read more.

This study aimed to determine the effect of irrigation amount (

W

), nitrogen (

N

), potassium (

K

), and zinc (

Z n

) on the net photosynthetic rate (

P n

) of closely planted apple trees on dwarf rootstocks in arid areas of Xinjiang. Taking the “Royal Gala” apple as the experimental material, a mathematical model for

P n

was established using the principle of four-factor five-level quadratic regression with a general rotation combination design. The results show that: (1) The regression equations reached significant levels (F = 37.06 > F_0.01(11.11) = 4.54). (2) The effect of

W

,

N

,

K

,

Z n

on

P n

is significant with relative importance

W

>

N

>

Z n

>

K

. (3) The results of single factor analysis showed that with an increase in W, N, K, and Zn,

P n

exhibits an n-shaped parabolic response. (4) The positive coupling between

W

and

N

is significant, and the positive coupling between

W

and

Z n

is also significant. (5) Analysis of the interaction between sets of three factors revealed that

W

,

N,

and

Z n

could be combined to best effect, with the maximum value reaching 12.77

μ mol \cdot m^{- 2} \cdot s^{- 1}

. Compared with

W \times K \times Z n

and

W \times N \times K

, the combination of

W \times N \times Z n

reduces

W

by 9.2% and 6.3%, respectively, which indicates its suitability for use in the dry and water deficient planting environment in Xinjiang. (6) Within the 95% confidence level, when

W

is 258–294.75 mm,

N

is 33.44–39.51

kg / {hm}^{2}

,

K

is 53.82–69.39

kg / {hm}^{2},

and

Z n

is 6.46–7.84

kg / {hm}^{2}

, the net photosynthetic rate reaches 11

μ mol \cdot m^{- 2} \cdot s^{- 1}

. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2107 KiB

Open AccessArticle

Impact of PGPR Formulations Combined with Exogenous IBA Levels to Enhance Root Capacity in Poinsettia Cuttings

by Fazilet Parlakova Karagöz

Agronomy 2023, 13(3), 878; https://doi.org/10.3390/agronomy13030878 - 16 Mar 2023

Viewed by 1505

Abstract

The commercial production of poinsettias begins with the propagation of apical cuttings from stock plants. The aim of the study was to use bacterial mixtures prepared with PGPRs in the cultivation of stock mother poinsettia plants and determine an effective IBA dose to [...] Read more.

The commercial production of poinsettias begins with the propagation of apical cuttings from stock plants. The aim of the study was to use bacterial mixtures prepared with PGPRs in the cultivation of stock mother poinsettia plants and determine an effective IBA dose to increase root development and root yield of cuttings prepared from these stock mother plants. Rooted cuttings of Euphorbia pulcherrima Willd.ex Klotzsch were used for planting stocks of mother plants. Eight different bacterial isolates were mixed in triple combinations to form 4 different bacterial formulations: (BI) formulation 1 (Paenibacillus polymyxa TV-12E + Pseudomonas putida TV-42A + Pantoea agglomerans RK-79); (BII) formulation 2 (Bacillus megaterium TV-91C + Pantoea agglomerans RK-92 + Bacillus subtilis TV-17C); (BIII) formulation 3 (Bacillus megaterium TV-91C + Pantoea agglomerans RK-92 + Kluyvera cryocrescens TV-113C); and (BIV) formulation 4 (Bacillus megaterium TV-91C + Pantoea agglomerans RK-79 + Bacillus megaterium TV-6D). In the first year, rooted cuttings of stock mother plants were dipped in liquid microbial solution (bacterial formulations) for 15 min and then planted in plastic pots. In the second year, the same bacterial formulations were freshly prepared and applied to the 1-year-old stock mother plants as irrigation water for the second time. Amounts of 0 (control), 1000, 1500, and 2000 mg L⁻¹ IBA doses were used for rooting cuttings taken from the 2-year-old stock mother plants. In the experimental group treated with the BI bacterial formulation, the number of rooted cuttings (NR) increased by 14.26% and 19.00%, compared with the control, in response to IBA 1500 mg L⁻¹ and IBA 2000 mg L⁻¹ treatment, respectively. Compared to the mean root length of the cuttings in the control treatment, the mean root length of the cuttings in the BIV treatment increased by 18.83%. The mean root length values decreased with the increase in IBA doses. The highest value of the number of mean shoots (NAS) was in cuttings treated with BI + 1500 treatment, which was 1.93 times higher than the control. The highest nitrogen content (5.73%) was determined in the bract leaf samples of the BIV application, and an 81.33% nitrogen increase was detected in the related application when compared to the control. In terms of P, Ca, and Fe contents, higher values were obtained from the BIV application when compared to the control application. The highest values of K content were determined in BIII and BII applications. This study provides positive effects on the feedback of stock mother plants with PGPR to provide sprout production by cuttings technique. It has been revealed that lower IBA dose applications can be recommended for rooting cuttings taken from mother plants treated with the BIV bacterial formulation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 2424 KiB

Open AccessArticle

Preparation of Zn−Gly and Se−Gly and Their Effects on the Nutritional Quality of Tea (Camellia sinensis)

by Feixia Li, Xinzhuan Yao, Litang Lu and Yujie Jiao

Plants 2023, 12(5), 1049; https://doi.org/10.3390/plants12051049 - 25 Feb 2023

Cited by 4 | Viewed by 1888

Abstract

Background: Micronutrient malnutrition affects millions of people due to a lack of Zn and Se. Methods: The process conditions for the manufacture of glycine−chelated sodium selenite (Se−Gly) and zinc sulfate heptahydrate (Zn−Gly) were studied. The effects of ligand concentration, pH, reaction ratio, reaction [...] Read more.

Background: Micronutrient malnutrition affects millions of people due to a lack of Zn and Se. Methods: The process conditions for the manufacture of glycine−chelated sodium selenite (Se−Gly) and zinc sulfate heptahydrate (Zn−Gly) were studied. The effects of ligand concentration, pH, reaction ratio, reaction temperature, and reaction time on fertilizer stability were assessed. The effects of Zn−Gly and Se−Gly on tea plants were determined. Results: Orthogonal experiments showed that the optimal preparation conditions for Zn−Gly (75.80 % Zn chelation rate) were pH 6.0, ligand concentration 4 %, reaction ratio 1:2, reaction time 120 min, reaction temperature 70 ℃. The optimal preparation conditions for Se−Gly (56.75 % Se chelation rate) were pH 6.0, ligand concentration 10%, reaction ratio 2:1, reaction time 40 min, temperature 50 ℃. Each chelate was completely soluble in water and verified by infrared spectroscopy and ultraviolet spectroscopy. Conclusions: Zn−Gly and Se−Gly increased the Zn and Se content in tea plants, and foliar application was more effective than soil application. Combined application of Zn−Gly and Se−Gly was more effective than Zn−Gly or Se−Gly alone. Our findings suggest that Zn−Gly and Se−Gly provide a convenient method of addressing human Zn and Se deficiency. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1723 KiB

Open AccessArticle

Growth and Nitrogen Uptake by Potato and Cassava Crops Can Be Improved by Azospirillum brasilense Inoculation and Nitrogen Fertilization

by Adalton Mazetti Fernandes, Jessica Aparecida da Silva, Juliana Aparecida Marques Eburneo, Magali Leonel, Francisca Gyslane de Sousa Garreto and Jason Geter da Silva Nunes

Horticulturae 2023, 9(3), 301; https://doi.org/10.3390/horticulturae9030301 - 23 Feb 2023

Viewed by 1575

Abstract

Nitrogen (N) is the nutrient most taken up by potato and cassava crops and Azospirillum brasilense may contribute to the growth of these crops. Pot experiments evaluated A. brasilense and mineral N application on leaf N concentration, plant growth, and N uptake by [...] Read more.

Nitrogen (N) is the nutrient most taken up by potato and cassava crops and Azospirillum brasilense may contribute to the growth of these crops. Pot experiments evaluated A. brasilense and mineral N application on leaf N concentration, plant growth, and N uptake by potato and cassava grown under natural and disinfected soil. The rates of 2.8 × 10⁸ colony-forming units mL⁻¹ of A. brasilense combined with 0, 75, 150, and 300 mg dm⁻³ N or 0, 50, 100, and 200 mg dm⁻³ N were used for potato or cassava grown. At low N supply in natural soil, A. brasilense inoculation increased N concentration in potato leaves by 23–38%, without benefits to plant growth or N uptake. At unfertilized N treatments of both soils, A. brasilense inoculation increased cassava leaf N concentration by 25–33%, but an 11–32% increase in shoot biomass occurred in treatments inoculated and N supplied. Potato crops responded positively to mineral N supply, but cassava responded to fertilization only in disinfected soil. In disinfected soil fertilized with N, A. brasilense inoculation increased cassava N uptake by 27–40%. In contrast, in natural soil, A. brasilense minimized the negative effect of N excess on the tuber development of cassava. These results show that the use of A. brasilense is a more interesting alternative to improve N status and growth in cassava than in potatoes. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 7308 KiB

Open AccessArticle

Effects of Nutrition and Light Quality on the Growth of Southern Highbush Blueberry (Vaccinium corymbosum L.) in an Advanced Plant Factory with Artificial Lighting (PFAL)

by Haishan An, Jiaying Zhang, Liqing Zhang, Shuigen Li, Boqiang Zhou and Xueying Zhang

Horticulturae 2023, 9(2), 287; https://doi.org/10.3390/horticulturae9020287 - 20 Feb 2023

Cited by 3 | Viewed by 2684

Abstract

A plant factory is a highly developed product system that can produce higher yields and better quality plants under controlled conditions. However, knowledge of blueberry cultivation in plant factories is limited. This study established an advanced plant factory with artificial lighting (PFAL) and [...] Read more.

A plant factory is a highly developed product system that can produce higher yields and better quality plants under controlled conditions. However, knowledge of blueberry cultivation in plant factories is limited. This study established an advanced plant factory with artificial lighting (PFAL) and investigated the effects of nutrition supply and light qualities on the growth performance of blueberries. Different nutrition treatments affected the vegetative growth of blueberries in PFAL, especially the new shoot length and number. Exogenous fertilization significantly promoted the uptake of N, P, and K elements, and a nutrition solution with N:P:K = 2:1:1 was suggested to be superior for blueberries in PFAL. Red light facilitated vegetative growth to some degree, and the blue light was conducive to increased chlorophyll and anthocyanin content. The Pn value was significantly enhanced under 60% red plus 40% blue light. Combining red and blue light is more beneficial to blueberry growth and might be a preferential strategy in PFAL. This study is the first to investigate the growth performance of blueberries cultivated in PFAL, which can provide an important theoretical database for blueberry cultivation in a plant factory with artificial lighting. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2588 KiB

Open AccessArticle

Hyperspectral Estimation of Soil Organic Carbon Content Based on Continuous Wavelet Transform and Successive Projection Algorithm in Arid Area of Xinjiang, China

by Xiaoyu Huang, Xuemei Wang, Kawuqiati Baishan and Baisong An

Sustainability 2023, 15(3), 2587; https://doi.org/10.3390/su15032587 - 01 Feb 2023

Cited by 4 | Viewed by 1536

Abstract

Soil organic carbon (SOC), an important indicator to evaluate soil fertility, is essential in agricultural production. The traditional methods of measuring SOC are time-consuming and expensive, and it is difficult for these methods to achieve large area measurements in a short time. Hyperspectral [...] Read more.

Soil organic carbon (SOC), an important indicator to evaluate soil fertility, is essential in agricultural production. The traditional methods of measuring SOC are time-consuming and expensive, and it is difficult for these methods to achieve large area measurements in a short time. Hyperspectral technology has obvious advantages in soil information analysis because of its high efficiency, convenience and non-polluting characteristics, which provides a new way to achieve large-scale and rapid SOC monitoring. The traditional mathematical transformation of spectral data in previous studies does not sufficiently reveal the correlation between the spectral data and SOC. To improve this issue, we combine the traditional method with the continuous wavelet transform (CWT) for spectral data processing. In addition, the feature bands are screened with the successive projection algorithm (SPA), and four machine learning algorithms are used to construct the SOC content estimation model. After the spectral data is processed by CWT, the sensitivity of the spectrum to the SOC content and the correlation between the spectrum and the SOC content can be significantly improved (p < 0.001). SPA was used to compress the spectral data at multiple decomposition scales, greatly reducing the number of bands containing covariance and enabling faster screening of the characteristic bands. The support vector machine regression (SVMR) model of CWT-R′ gave the best prediction, with the coefficients of determination (R²) and the root mean square error (RMSE) being 0.684 and 1.059 g∙kg⁻¹, respectively, and relative analysis error (RPD) value of 1.797 for its validation set. The combination of CWT and SPA can uncover weak signals in the spectral data and remove redundant bands with covariance in the spectral data, thus realizing the screening of characteristic bands and the fast and stable estimation of the SOC content. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 1135 KiB

Open AccessArticle

Green Manure Amendment Increases Soil Phosphorus Bioavailability and Peanut Absorption of Phosphorus in Red Soil of South China

by Chiming Gu, Weisheng Lv, Xing Liao, Margot Brooks, Yinshui Li, Changbin Yu, Lu Yang, Xiaoyong Li, Wenshi Hu, Jing Dai, Wei Zheng and Lu Qin

Agronomy 2023, 13(2), 376; https://doi.org/10.3390/agronomy13020376 - 27 Jan 2023

Cited by 3 | Viewed by 1567

Abstract

Peanut (Arachis hypogaea L.) is one of the most important crops produced worldwide. Peanut is the dominant crop in the typical upland red soil areas of China; however, phosphorus bioavailability in red soil is very low, which severely affects peanut production. To [...] Read more.

Peanut (Arachis hypogaea L.) is one of the most important crops produced worldwide. Peanut is the dominant crop in the typical upland red soil areas of China; however, phosphorus bioavailability in red soil is very low, which severely affects peanut production. To improve the phosphorus bioavailability, which substantially promotes the green development of peanut production, a peanut–green manure rotation field experiment was conducted with six treatments (milkvetch; radish; brassica rape; mustard rape; winter fallow and no-tillage), commencing in September 2017 in the red soil area of Jiangxi province, China. The results show that compared with no-tillage (NT) treatments, different green manure returning treatments had significant effects on soil pH, soil phosphorus components and available potassium content. The particulate phosphorus and soil available phosphorus contents in the green manure treatments were significantly higher than those in the winter fallow (WF) treatment. Compared with the WF treatment, the content of particulate phosphorous in brassica rape (BR), radish (R) and milkvetch (MV) treatments was significantly increased by 6.55%, 3.66% and 2.50%, respectively; the available phosphorus content in mustard rape (MR), BR, R and MV was significantly increased by 20.93%, 25.60%, 23.76% and 18.10%, respectively. In addition, the total phosphorus content of peanut shell in the MV and R treatment was significantly higher than that in the WF treatment, increasing by 33.47% and 60.66%, respectively. Compared with the WF treatment, the peanut biomass of MR, BR and R treatments increased significantly by 19.51%, 29.83% and 19.77%, respectively. The total phosphorus accumulation in all green manure treatments was higher than that in the WF treatment, and the MV treatment reached a significant level at 18.83%. Based on these results, the particulate phosphorus (PP) and available phosphorus were significantly affected by different green manure treatments; green manure amendment improves peanut phosphorus uptake. The use of green manure (especially milkvetch and brassica rape) can be recommended to improve phosphorus bioavailability and yield of peanut in red soil areas. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 2105 KiB

Open AccessArticle

Biochar Integrated Nutrient Application Improves Crop Productivity, Sustainability and Profitability of Maize–Wheat Cropping System

by Naeem Sarwar, Naseem Abbas, Omer Farooq, Muhammad Akram, Muhammad Waqar Hassan, Khuram Mubeen, Atique-ur Rehman, Muhammad Shehzad, Matlob Ahmad and Abdul Khaliq

Sustainability 2023, 15(3), 2232; https://doi.org/10.3390/su15032232 - 25 Jan 2023

Cited by 3 | Viewed by 2498

Abstract

Enhancing cereal crop production to feed the largely growing population is an important approach towards maintaining food security. Fertilizer management is the major component of crop production requiring special attention for sustainable application. Integrated nutrient management (INM) is an evolving idea, which appears [...] Read more.

Enhancing cereal crop production to feed the largely growing population is an important approach towards maintaining food security. Fertilizer management is the major component of crop production requiring special attention for sustainable application. Integrated nutrient management (INM) is an evolving idea, which appears to contribute to sustainable nutrient management. A field study was designed to see the impact of INM on a maize–wheat cropping system during winter (wheat) and summer (maize) season at Agronomic Research Farm, Bahauddin Zakariya University Multan, Pakistan. Both wheat and maize crops were grown consecutively along with full inorganic fertilizer (NPK) as well as with partial dose of fertilizer (25%, 50%, 75% NPK) supplemented with or without the addition of biochar (5 ton/ha). Data were collected regarding crop growth, yield and quality and further analyzed using MSTAT-C statistics software. Results revealed that the INM approach (75% of NPK + Biochar) enabled crops to improve dry matter production and its translocation towards sink which in turn boosted the crop productivity. This treatment improved dry matter (19%, 57%), grain weight (44%, 54%), grain yield (60%, 63%) and harvest index (30%, 29%) over the control in maize and wheat crops. It also improved the nutrient uptake in the plants which in turn improved the nutrient contents in the grains. Similarly, crops recorded higher system productivity (USD 790, USD 830) in both years and were found to be economically sustainable under INM. It was concluded that an INM strategy (75% of NPK + Biochar) can improve the productivity and sustainability of a maize–wheat cropping system to maintain the food security. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 5192 KiB

Open AccessArticle

Organo-Mineral Fertilization Based on Olive Waste Sludge Compost and Various Phosphate Sources Improves Phosphorus Agronomic Efficiency, Zea mays Agro-Physiological Traits, and Water Availability

by Youness Bouhia, Mohamed Hafidi, Yedir Ouhdouch, Youssef Zeroual and Karim Lyamlouli

Agronomy 2023, 13(1), 249; https://doi.org/10.3390/agronomy13010249 - 14 Jan 2023

Cited by 6 | Viewed by 2897

Abstract

In the context of intensive and sustainable agriculture, limiting soil degradation and the loss of organic matter has become an obligation to maintain food security. The use of organo-mineral fertilizer (OMF) products is an innovative technology that may solve the different challenges raised. [...] Read more.

In the context of intensive and sustainable agriculture, limiting soil degradation and the loss of organic matter has become an obligation to maintain food security. The use of organo-mineral fertilizer (OMF) products is an innovative technology that may solve the different challenges raised. This study aimed to evaluate the effect of various organo-mineral fertilizer (OMF) formulations on Zea mays agro-physiological traits, phosphorus (P)-related parameters, and water conservation during a 90-day pot experiment. The OMF formulations consisted of blending several doses of a stable OMWS compost (10 t /ha(OMF1), 50 t/ha (OMF2), or 100 t/ha (OMF3)) with different sources of mineral P, namely diammonium phosphate (DAP), rock phosphate (RP), or phosphate washing sludge (PWS), compared with separate applications. The results indicated that the effect of an OMF on the soil and plants was strongly dependent on the source of P used and the dose of OMWS compost. The best agronomic performance was attributed to OMF1-based DAP, which resulted in a significant improvement in the shoot and root biomass dry weight by more than 260% and 40%, respectively. However, using an OMF2 formulation was more optimal when using RP and PWS as mineral P sources. Independently of the type of P fertilizer, the addition of stable OM systematically improved multiple soil properties, including water availability, and the nutrient concentrations, such as the available P, exchangeable potassium, and magnesium. Furthermore, the plant’s respiration, photosynthetic activity, and nutrient assimilations were positively affected by the OMF formulations. Overall, our results demonstrate that organo-mineral fertilization is a promising solution for increasing the efficiency of low-P and high-P mineral fertilizers in alkaline soils through direct and indirect mechanisms involving improved soil properties and higher P solubilization. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 3485 KiB

Open AccessArticle

Changes in Foxtail Millet (Setaria italica L.) Yield, Quality, and Soil Microbiome after Replacing Chemical Nitrogen Fertilizers with Organic Fertilizers

by Ming-Jie Sun, Ying Chao, Wei He, Xi-Rui Kang, Quan-Gang Yang, Hui Wang, Hong Pan, Yan-Hong Lou and Yu-Ping Zhuge

Sustainability 2022, 14(24), 16412; https://doi.org/10.3390/su142416412 - 08 Dec 2022

Cited by 2 | Viewed by 2334

Abstract

Foxtail millet (Setaria italica L.) is one of the most economically valuable drought-resistant crops in arid and semi-arid regions as a nutrition health crop, which has garnered considerable research attention. We evaluated the effects of replacing chemical nitrogen fertilizers with organic fertilizers [...] Read more.

Foxtail millet (Setaria italica L.) is one of the most economically valuable drought-resistant crops in arid and semi-arid regions as a nutrition health crop, which has garnered considerable research attention. We evaluated the effects of replacing chemical nitrogen fertilizers with organic fertilizers on two primary plant accessions of foxtail millet (Dungu and Jinfen no. 2). Nitrogen in a standard fertilizer was replaced with organic fertilizer at application levels of 0, 25, 50, 75, and 100%, with effects on crop yield, quality (appearance, taste, and nutritional value), and soil microbiome, assessed using field cultivation experiments. Our results indicate that partial replacement of conventional fertilizers with organic fertilizers improved both yield and quality. Specifically, the 75% replacement significantly improved the appearance (yellow pigment content and grain diameter) and taste (amylose content and soluble sugar content) of foxtail millet, while the 50% replacement significantly improved the taste (gel consistency) and nutritional qualities (crude protein content and seven amino acids’ content). The 50% replacement of organic fertilizer regulated amino acid content more significantly than starch content. Increased ratios of organic fertilizer significantly reduced the soil pH by 0.03–0.36 and increased the relative abundance of Chloroflexi as well as that of Basidiomycota and Cercozoa in the soil microbiome. Our findings provide a solid theoretical foundation for subsequent studies on fertilizer use for foxtail millet and contribute to developing functional nutritional foods in the foxtail millet industry. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 9895 KiB

Open AccessArticle

Properties of Recycled Nanomaterials and Their Effect on Biological Activity and Yield of Canola in Degraded Soils

by Hany Elsawy, Asmaa El-shahawy, Mahmoud Ibrahim, Abd El-Halim Abd El-Halim, Naser Talha, Azza Sedky, Manal Alfwuaires, Hebah Alabbad, Nawa Almeri and Esawy Mahmoud

Agriculture 2022, 12(12), 2096; https://doi.org/10.3390/agriculture12122096 - 07 Dec 2022

Cited by 5 | Viewed by 1624

Abstract

Recycling waste, such as rice straw and water treatment residuals, is important to reduce harmful effects on the environment and to improve canola yield and soil quality in degraded soils. Nanotechnology for the production of nanomaterials from biochar and water treatment residues will [...] Read more.

Recycling waste, such as rice straw and water treatment residuals, is important to reduce harmful effects on the environment and to improve canola yield and soil quality in degraded soils. Nanotechnology for the production of nanomaterials from biochar and water treatment residues will be a future revolution for improving soil quality and increasing canola yield in degraded soil. Therefore, this study aims to identify the properties of some recycled nanomaterials, such as nanobiochar (nB) and nanowater treatment residue (nWTR), and their effect on the biological activity and productivity of canola in degraded soils. The results showed that the nWTR and nB contain many functional groups and minerals, and they also have high negative zeta potential. The addition of the studied soil amendments significantly improved microbial biomass carbon (MBC) and biological activity, which played a major role in increasing canola yield. The highest dehydrogenase (DHA) and catalase (CLA) activity was found in nWTR-treated soil at 50 mg kg⁻¹, with increases of 32.8% and 566.7% compared to the control, respectively. The addition of nB greatly improved the growth of canola plants in the soil. This was evident from the increase in the weight of seeds, the weight of 1000 grains, the number of pods per plant, and the highest increase was for nB added at the rate of 250 mg per kg⁻¹ soil. The addition of 50 mg kg⁻¹ of nWTR gave the best results in seed yield by 150.64% compared to the control. These results indicate that recycled nWTR and nB are some of the best waste recycling treatments, in addition to good soil health, in increasing soil biology and canola yield in degraded soils. In the future, research on recycled nanomaterials should examine the residual effect they have on yield, soil quality, and soil fauna in the long term. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 2498 KiB

Open AccessArticle

Nitrogen Fertilizer Reduction Combined with Biochar Application Maintain the Yield and Nitrogen Supply of Rice but Improve the Nitrogen Use Efficiency

by Chuanchuan Ning, Rui Liu, Xizhi Kuang, Hailang Chen, Jihui Tian and Kunzheng Cai

Agronomy 2022, 12(12), 3039; https://doi.org/10.3390/agronomy12123039 - 01 Dec 2022

Cited by 9 | Viewed by 1891

Abstract

Excessive application of nitrogen (N) fertilizer will cause many adverse consequences in paddy fields, especially for the reduction in N use efficiency. Biochar can be used to replace part of N fertilizer for rice production. A field experiment of 2-year/four-season was conducted to [...] Read more.

Excessive application of nitrogen (N) fertilizer will cause many adverse consequences in paddy fields, especially for the reduction in N use efficiency. Biochar can be used to replace part of N fertilizer for rice production. A field experiment of 2-year/four-season was conducted to investigate the effects of N fertilizer reduction combined with rice straw biochar application on rice yield, soil fertility, and N use efficiency. The experiment contained six treatments: No N application (CK), customary N application (N100), 20% N reduction (N80), 20% N reduction + biochar (N80+BC), 40% N reduction (N60), and 40% N reduction + biochar (N60+BC). Compared with N100, N reduction alone had no significant impact on the number of tillers and aboveground biomass of rice, exceptfor N60 which slightly reduced grain yield, while biochar incorporation tended to obtain higher tillers, aboveground biomass, and grain yield of rice compared with N reduction alone. The average contribution of biochar to grain yield on the basis of N80 and N60 were 5.8% and 7.7%, respectively. Notably, biochar incorporation further improved the agronomic N efficiency (54.5–309.4% over N100) and apparent N recovery (25.7–150.5% over N100) on the basis of N reduction. Furthermore, biochar application could not only maintain N nutrition level of rice, but also improve soil fertility mainly by increasing soil pH and organic matter. Therefore, integrated application of mineral N fertilizer and biochar is a feasible nutrient management measure to increase rice yield and soil fertility, and improve N use efficiency in paddy ecosystem. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1180 KiB

Open AccessArticle

Growth Performance of Guava Trees after the Exogenous Application of Amino Acids Glutamic Acid, Arginine, and Glycine

by Khalid F. Almutairi, Abaidalah A. Saleh, Muhammad Moaaz Ali, Lidia Sas-Paszt, Hesham S. Abada and Walid F. A. Mosa

Horticulturae 2022, 8(12), 1110; https://doi.org/10.3390/horticulturae8121110 - 25 Nov 2022

Cited by 2 | Viewed by 2082

Abstract

A 2020–2021 study was performed on five-year-old guava trees to examine the influence of the foliar application of three amino acids, glycine, arginine, and glutamic acid, at a concentration of 500 or 1000 ppm. Additionally, two combinations of the three mentioned amino acids [...] Read more.

A 2020–2021 study was performed on five-year-old guava trees to examine the influence of the foliar application of three amino acids, glycine, arginine, and glutamic acid, at a concentration of 500 or 1000 ppm. Additionally, two combinations of the three mentioned amino acids were also applied: 500 glycine + 500 arginine + 500 glutamic acid (combination 1) and 1000 glycine + 1000 arginine + 1000 glutamic acid (combination 2), and compared with a control (untreated trees). The results indicated that the application of the three amino acids, solely or in combination, was effective at increasing the shoot length, shoot diameter, and leaf chlorophyll. Additionally, the applied treatments also improved markedly the fruit set percentage, fruit yield, fruit firmness, fruit content of total soluble solids (TSS %), vitamin C (VC), and total sugars as well as the leaf mineral content (nitrogen, potassium, and phosphorus) compared with untreated trees in 2020 and 2021. Moreover, the results indicated that the combinations were more effective than individual applications and that glycine had a greater influence than arginine or glutamic acid, particularly when it was applied at 1000 ppm. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 3573 KiB

Open AccessArticle

The Impact of Viticulture on Soil Characteristics and Microbial Communities in the Ningxia Region of Northwest China

by Tingting Xue, Fan Yang, Ruyi Li, Yue Li, Guoqian Xu and Liang Zhang

Horticulturae 2022, 8(12), 1097; https://doi.org/10.3390/horticulturae8121097 - 22 Nov 2022

Cited by 1 | Viewed by 1363

Abstract

Winegrape cultivation has become increasingly common throughout northwest China over the past 20 years, and such viticulture can profoundly impact the properties of the utilized soil and the associated soil microbial communities. To explore these effects in the present study, samples of soil [...] Read more.

Winegrape cultivation has become increasingly common throughout northwest China over the past 20 years, and such viticulture can profoundly impact the properties of the utilized soil and the associated soil microbial communities. To explore these effects in the present study, samples of soil were collected from control desert soil and from vineyards planted in different years: Cabernet Sauvignon (CS, 2014), Merlot (M, 2012), and Italian Riesling (IR, 2008). The properties of this soil and the microbial communities therein were assessed through a series of physicochemical, enzymatic, and high-throughput sequencing analyses. Compared to the control soil, respective 1033.06 U/g, 398.28 U/g, and 240.56 U/g increases in alkaline phosphatase activity levels were observed in the CS, M, and IR soil samples. Stable soil bacterial richness was observed in the control, CS, and M samples, but decreased in the 11-years old IR soil, whereas no noticeable changes in soil fungi were observed across these samples. The network analyses highlighted correlations among soil microbes, and soil organic carbon and microbial biomass carbon were found to strongly influence variability in these soil microbial communities. Overall, these findings thus provide strong evidence that the prolonged monoculture of winegrapes can contribute to the deterioration of soil quality. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 374 KiB

Open AccessArticle

The Response of Weeds and Apple Trees to Beneficial Soil Microorganisms and Mineral Fertilizers Applied in Orchards

by Jerzy Lisek, Lidia Sas-Paszt, Augustyn Mika and Anna Lisek

Agronomy 2022, 12(11), 2882; https://doi.org/10.3390/agronomy12112882 - 17 Nov 2022

Cited by 2 | Viewed by 1788

Abstract

The effect of beneficial soil fungi, bacteria and mineral fertilizers containing nitrogen, phosphorus and potassium on the level and species composition of weed infestation, uptake of macronutrients by weeds and the nutritional status of ‘Sampion’ apple trees with nitrogen (N), phosphorus (P), potassium [...] Read more.

The effect of beneficial soil fungi, bacteria and mineral fertilizers containing nitrogen, phosphorus and potassium on the level and species composition of weed infestation, uptake of macronutrients by weeds and the nutritional status of ‘Sampion’ apple trees with nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg) and calcium (Ca) was assessed in three-year studies. In the field experiment, the effect of thirteen treatments was investigated, where fungal or bacterial inocula and mineral fertilizers at a standard dose and a dose reduced by 40% were applied individually or together. The fungal inoculum contained two species: Aspergillus niger and Purpureocillium lilacinum. The bacterial consortium consisted of three Bacillus strains: Bacillus sp., Bacillus amyloliquefaciens and Paenibacillus polymyxa. The weight of weeds and the uptake of macronutrients by weeds in the apple orchard increased significantly more after the application of mineral fertilization than after the application of beneficial organisms. The increased uptake of macronutrients by weeds did not significantly change the mineral nutritional status of apple trees expressed as the content of N, P, K Mg and Ca in apple leaves. After the use of NPK mineral fertilization, also with the addition of beneficial organisms, the uptake of N by both weeds and apple trees increased. P and K were more efficiently absorbed by weeds and they achieved greater benefits from fertilization with these two macroelements than trees. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

16 pages, 1043 KiB

Open AccessArticle

Excessive Delay in Nutrient Release by Controlled-Release Fertilizers Can Reduce Chestnut Yield

by Margarida Arrobas, Leonardo Bomfim Belotto, Juliana Aparecida Marchetti, Valdemar Barroso, Soraia Raimundo, Luís César Cassol, Carlos Manuel Correia and Manuel Ângelo Rodrigues

Horticulturae 2022, 8(11), 1067; https://doi.org/10.3390/horticulturae8111067 - 14 Nov 2022

Cited by 2 | Viewed by 1407

Abstract

Farmers are increasing the use of fertilizers in chestnut, the only cash crop produced in the mountainous areas of northeastern Portugal. This calls for more studies to guide them towards a more ecological intensification. The effects of three controlled-release fertilizers, two that release [...] Read more.

Farmers are increasing the use of fertilizers in chestnut, the only cash crop produced in the mountainous areas of northeastern Portugal. This calls for more studies to guide them towards a more ecological intensification. The effects of three controlled-release fertilizers, two that release nutrients over three months (BoskGrow 20:05:20_3m, Exactyon 18:05:13_3m) and one over six months (Exactyon 18:05:12_6m), and an organic amendment authorized for organic farming (Humix 12:03:05) were compared with an untreated control during a three-year field trial (2019–2021). BoskGrow 20:05:20_3m, Exactyon 18:05:13_3m and Humix 12:03:05 gave significantly higher nut yields (90.6 to 97.0 kg tree⁻¹, average 2019 + 2021) than Exactyon 18:05:12_6m (66.3 kg tree⁻¹) and the control (69.5 kg tree⁻¹). Leaf concentrations of nitrogen and potassium tended to be higher in the BoskGrow 20:05:20_3m and Exactyon 18:05:13_3m treatments, and they were stated as the most important causes in the establishment of the two productive groups. Humix 12:03:05, although less concentrated in nutrients, led to a chestnut yield at the level of the most productive treatments, possibly due to the multiple positive effects of organic matter on soil and plants. Under the conditions of this experiment, where rainfall is low in the summer, fertilizers whose nutrient release takes a long time, such as Exactyon 18:05:12_6m, seem not to be a good fertilization option due to reduced nutrient uptake and increased levels of soil inorganic nitrogen at the end of the growing season. Humix 12:03:05 emerged as a possible solution for organic producers. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 2963 KiB

Open AccessArticle

Straw Management and Slurry Application Affect the Soil Microbial Community Composition and Its Activity

by Sara Pintarič, Marjetka Suhadolc and Klemen Eler

Agronomy 2022, 12(11), 2781; https://doi.org/10.3390/agronomy12112781 - 09 Nov 2022

Cited by 1 | Viewed by 1563

Abstract

In low-input farming systems, where plant nutrition strongly depends on either organic matter inputs or nitrogen fixation by legumes, it is crucial to understand the effects of different crop residue management strategies on microbially mediated processes that influence nutrient dynamics. To evaluate different [...] Read more.

In low-input farming systems, where plant nutrition strongly depends on either organic matter inputs or nitrogen fixation by legumes, it is crucial to understand the effects of different crop residue management strategies on microbially mediated processes that influence nutrient dynamics. To evaluate different straw management options, we conducted a pot experiment with the following treatments: (1) control with no straw added (CON), (2) applying straw to the soil surface (SRF), simulating no-till, and (3) straw incorporating straw to the top 10 cm (INC), simulating minimum tillage. Another factor was slurry fertilization (with 3.2 t d.m. ha⁻¹ or without). Throughout the experiment, CO₂ efflux (µmol/m²/s) was measured regularly over a period of four months. Soil sampling was performed to monitor the abundance of the total bacterial, crenarchaeal and fungal communities, as well as nitrogen cycle microbial guilds and the dynamics of labile N and C fractions in the soils at different depths. Among straw treatments, significantly higher soil respiration was observed in INC and SRF compared to CON. Slurry fertilization increased soil respiration in all straw treatments. In the top 10 cm soil layer, the fungal abundance increased in INC compared to SRF and CON, whereas bacteria and crenarchaea did not respond. This effect was even more pronounced with slurry addition. The slurry also stimulated the abundance of certain N-cycle guilds, with the greatest increase in bacterial amoA-bearing nitrifiers and nirS, nosZI and nozII-bearing denitrifiers, particularly in the uppermost 0–1 cm soil layer. Straw treatment effects on N-cycle microbial guilds were less pronounced, while the coupled effect of straw incorporation and slurry was beneficial mostly for nosZ, again mainly in the top 1 cm soil layer. Compared to straw management, slurry fertilization had more potent effects on the abundance and performance of the investigated microbial communities. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 3230 KiB

Open AccessArticle

Phenology Based Variability of Tissue Nutrient Content in Mature Muscadine Vines (Vitis rotundifolia cv. Carlos)

by Kyle Austin Freedman, Tekan Singh Rana and Mark Hoffmann

Agriculture 2022, 12(11), 1805; https://doi.org/10.3390/agriculture12111805 - 29 Oct 2022

Viewed by 1313

Abstract

Muscadine (Vitis rotundifolia) is a grape species that is native to the Southeastern US, where several cultivars are grown commercially for processing or direct consumption. Phenology based tissue analysis to determine the nutritional status of a vine is a critical tool [...] Read more.

Muscadine (Vitis rotundifolia) is a grape species that is native to the Southeastern US, where several cultivars are grown commercially for processing or direct consumption. Phenology based tissue analysis to determine the nutritional status of a vine is a critical tool for growers to understand fertilizer demands in a vineyard. For European-style wine grapes, tissue sampling for nutrient content is well researched. However, current tissue sampling recommendations for muscadines are solely based on anecdotal knowledge. It is currently unknown if the type of tissue collected has an impact on variability and content of nutrients. Questions also remain as to whether or not seasonal vine phenology impacts tissue nutrient content. Without this knowledge it is difficult for a muscadine grower to make informed decisions on the nutritional status of a muscadine vine. Therefore, we investigated the impact of the phenological vine stage (bloom, fruit set, véraison) on nutrient content in two different tissue types (mature leaf vs. petiole), sampled at two different positions on a muscadine vine (opposite of cluster vs. shoot). The study was conducted over two growing seasons (2019 and 2020) in a commercial mature muscadine vineyard (‘Carlos’). Our results show that over both study years, the highest variability in nutrient content was found during bloom (May–June), while nutrient variability was lower during fruit-set and veraison. We also found fully mature leaf samples showed a lower variability in nutrient tissue content. Based on our results, sampling fully mature leafs from shoots remains the best practice. However, our results also indicate that tissue sampling later in the season might be a better practice, compared to the current practice of taking samples during June. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1327 KiB

Open AccessArticle

Phosphorus Availability from German Sewage Sludge Ashes to Plants Cultivated in Soilless Growing Media of Contrasting pH

by Daniel Hauck, Dieter Lohr, Elke Meinken and Urs Schmidhalter

Agronomy 2022, 12(11), 2610; https://doi.org/10.3390/agronomy12112610 - 24 Oct 2022

Cited by 2 | Viewed by 1450

Abstract

Sewage sludge ash (SSA) as a secondary phosphorus (P) source may help to conserve global rock phosphate deposits if used in the base fertilization of soilless growing media. Plant availability of SSA-P was studied in a pot experiment with marigolds in a peat-based [...] Read more.

Sewage sludge ash (SSA) as a secondary phosphorus (P) source may help to conserve global rock phosphate deposits if used in the base fertilization of soilless growing media. Plant availability of SSA-P was studied in a pot experiment with marigolds in a peat-based growing medium of contrasting pH (4.5, 6.0). Six SSAs were included in the study and compared to water-soluble monocalcium phosphate (MCP) and rock phosphate (RockP). In addition to the efficacy of SSA-P, calcium chloride + diethylenetriaminepentaacetate (CAT) and calcium-acetate-lactate (CAL), as commonly used extractants in Germany to analyze plant-available P in growing media, were tested in terms of their ability to predict plant P uptake. No SSA reached the relative P use efficiency (rPUE) observed for MCP. However, at a growing medium pH of 4.5, the average rPUE for SSA was 70% of the MCP rPUE. Compared to RockP, at a growing medium pH of 6.0, SSAs resulted in an rPUE of nearly the same low level. In contrast, at pH 4.5, the rPUE from SSAs was mostly lower than that from RockP, and there were differences in rPUE among SSA origins. Therefore, in addition to a variation in particle size distribution, there might be differences in the P-bearing phase. Sewage sludge ashes represent a promising substitute for primary P sources only in crops requiring a low pH in the growing medium. The extractants CAT and CAL, on their own or in combination, did not reflect plant P uptake from SSA. To improve the prediction of plant-available SSA-P, solvent modifications or additional extractants might be promising and should be subjected to further research. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1181 KiB

Open AccessArticle

Phosphorus Fractions in Temperate Grassland Soils and Their Interactions with Agronomic P Tests

by Jessica Graça, Giulia Bondi, Achim Schmalenberger and Karen Daly

Agronomy 2022, 12(10), 2569; https://doi.org/10.3390/agronomy12102569 - 19 Oct 2022

Cited by 5 | Viewed by 1432

Abstract

Phosphorus (P) is a major nutrient for plant growth and animal health, and its availability in soil is influenced by agronomic management and soil properties. This study examined the distribution of labile and non-labile soil P fractions in grassland and the properties that [...] Read more.

Phosphorus (P) is a major nutrient for plant growth and animal health, and its availability in soil is influenced by agronomic management and soil properties. This study examined the distribution of labile and non-labile soil P fractions in grassland and the properties that influence their distribution in temperate grasslands. Eleven fractions were identified as, labile (H₂O.P and NaHCO₃.P), moderately labile (NaOH.P) and plant non-available (NaOH.P, HCl.P and residual P). The residual P, moderately labile organic (NaOH.Po) and inorganic (NaOH.Pi) fractions comprised 38%, 24% and 15% of the total P (TP), respectively. The residual and organic (Po) fractions were associated with extractable Fe, and the NaOH.Pi fraction was associated with extractable Al. Agronomic reagents (Morgan’s and Mehlich3) targeted specific fractions based on their affinity for different soil elements. Morgan’s P was associated with extractable and residual Ca and in high Ca soils, and overestimated plant-available P by extracting non-labile Ca.P forms (HCl.P). The Mehlich3 P test was associated with NaOH.Pi fraction and showed a preference for Al.P oxides. This study indicates that Mehlich3 reagent, which provides a wider suite of elements such as P, Ca, Al and Fe, will suit as a better indicator for soil P dynamics and improved P advice to farmers. The inclusion of additional soil chemico-physical characteristics would improve agronomic soil testing, benefitting farmers’ advice. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 2316 KiB

Open AccessArticle

Reducing Macronutrients and Increasing Micronutrient Fertilizers Are Key to Improving the Quality of Pomelo Citrus grandis (L.) Osbeck Cv. “Guanxi”

by Xiaodong Liu, Chengxiao Hu, Muhammad Riaz, Xiaoman Liu, Xuecheng Sun, Mulai Zhuang and Qiling Tan

Agriculture 2022, 12(10), 1711; https://doi.org/10.3390/agriculture12101711 - 17 Oct 2022

Cited by 3 | Viewed by 1874

Abstract

Due to long-term excessive fertilization, the fruit quality of the Guanxi pomelo (Citrus grandis) has been declining. The classification of fruit quality and its relationship with nutrients in soils and trees were studied to declaim the characteristics of nutrients in Guanxi pomelo orchards, [...] Read more.

Due to long-term excessive fertilization, the fruit quality of the Guanxi pomelo (Citrus grandis) has been declining. The classification of fruit quality and its relationship with nutrients in soils and trees were studied to declaim the characteristics of nutrients in Guanxi pomelo orchards, ultimately guiding the fertilization for high-quality fruit production. By cluster analysis, 281 samples were grouped into four clusters. High-quality fruit (HF) showed a gourd shape with moderate weight size, high sweetness, edible rate (ER) up to 73%, and vitamin C content over 40 mg/100 g. Compared to sub-quality fruit (SF), common fruit (CF), and inferior fruit (IF), the content of magnesium (Mg) in the leaves of HF was 11.76, 11.76, and 18.75% higher, while the content of iron (Fe) was 6.45, 5.76 and 10.97% higher, respectively. Meanwhile, the contents of Zinc (Zn, 8.51, 6.44, and 11.22% higher than SF, CF, and IF, respectively) and Boron (B, 13.47, 13.83, and 25.40% higher than SF, CF, and IF, respectively) were also found to increase. However, the contents of Mn (35.34, 27.51, and 25.53% higher) and Cu (31.90, 31.99, and 5.64% higher) in IF were significantly higher than in HF, SF, and CF. Acid soils (4.24–4.40) with low OM content (23.00–26.71 g kg⁻¹) led to an imbalance uptake of nutrients of citrus, ultimately resulting in poor quality. These results indicated that farmers should reduce the application of nitrogen (N), phosphorus (P), and K fertilizer and pesticides and increase micronutrient and organic fertilizer, which provides a theoretical basis for scientific fertilization to improve the fruit quality of Guanxi pomelo (Citrus grandis) of Pinghe County. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 3322 KiB

Open AccessArticle

UAV-Derived Spectral Indices for the Evaluation of the Condition of Rye in Long-Term Field Experiments

by Elżbieta Wójcik-Gront, Dariusz Gozdowski and Wojciech Stępień

Agriculture 2022, 12(10), 1671; https://doi.org/10.3390/agriculture12101671 - 12 Oct 2022

Cited by 6 | Viewed by 1813

Abstract

The aim of the study was to evaluate the effect of various fertilization treatments, including nitrogen, potassium and phosphorus fertilization, in long-term experiments for selected UAV (unmanned aerial vehicle)-derived spectral vegetation indices (NDVI—Normalized Difference Vegetation Index, NDRE—Normalized Difference Red Edge Index, VARI—Visible Atmospherically [...] Read more.

The aim of the study was to evaluate the effect of various fertilization treatments, including nitrogen, potassium and phosphorus fertilization, in long-term experiments for selected UAV (unmanned aerial vehicle)-derived spectral vegetation indices (NDVI—Normalized Difference Vegetation Index, NDRE—Normalized Difference Red Edge Index, VARI—Visible Atmospherically Resistant Index, TGI—Triangular Greenness Index, SIPI2—Structure Insensitive Pigment Index 2, LCI—Leaf Chlorophyll Index, BNDVI—Blue Normalized Difference Vegetation Index, GNDVI—Green Normalized Difference Vegetation Index, MCARI—Modified Chlorophyll Absorption in Reflective Index) based on multispectral (bands in the range of visible light and near infra-red) images of winter rye. The strongest effect on the studied vegetation indices was nitrogen fertilization, which discriminated values of most of the vegetation indices. The effect of phosphorus and potassium fertilization on the studied vegetation indices was much weaker. The treatments with nitrogen fertilization had significantly higher values of most vegetation indices in comparison to treatments without nitrogen. This was confirmed by principal component analysis (PCA), in which treatments without nitrogen fertilization were very different in comparison to all other treatments where nitrogen fertilization was applied. The effect of phosphorus and potassium fertilization on most of vegetation indices was relatively weak and not significant in most experiments. Only for rye cultivated in monoculture was the effect of phosphorus fertilization significant for most of vegetation indices in early growth stages. In later growth stages (heading and flowering) the effect of phosphorus fertilization was significant in rye monoculture for the SIPI2 vegetation index. Mean SIPI2 was higher for the fertilization treatment CaNPK in comparison to CaKN (without P fertilization). The effect of potassium fertilization on the studied vegetation indices was very weak, and in most cases not significant. The effect of nitrogen fertilization on vegetation indices was much stronger than effect of both potassium and phosphorus fertilization. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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9 pages, 269 KiB

Open AccessArticle

Effects of Neem Seed Extract on Nitrate and Oxalate Contents in Amaranth Fertilized with Mineral Fertilizer and Cricket Frass

by Pranee Sriraj, Banyong Toomsan and Somchai Butnan

Horticulturae 2022, 8(10), 898; https://doi.org/10.3390/horticulturae8100898 - 29 Sep 2022

Viewed by 2139

Abstract

A vegetable’s high antinutrients, nitrate (NO₃⁻) and oxalate, could be remediated by neem seed extract. The combined use of neem seed extract with mineral fertilizer and cricket frass was conducted to evaluate their effects on amaranth’s tissue NO₃⁻ [...] Read more.

A vegetable’s high antinutrients, nitrate (NO₃⁻) and oxalate, could be remediated by neem seed extract. The combined use of neem seed extract with mineral fertilizer and cricket frass was conducted to evaluate their effects on amaranth’s tissue NO₃⁻ and oxalic acid contents by inhibiting nitrification. The effects of five soil amendments were investigated: unamended, mineral fertilizer, and three rates of cricket frass (3.125 Mg ha⁻¹, 6.25 Mg ha⁻¹, and 12.5 Mg ha⁻¹), combined with two rates of neem seed extract: without (−Nm) and with (+Nm) extract. Only the neem extract applied to soils receiving mineral fertilizers decreased soil tissue NO₃⁻−N contents (0.82 g kg⁻¹ for −Nm vs. 0.62 g kg⁻¹ for +Nm). The oxalic acid content of amaranth decreased with mineral fertilizer (0.60 and 0.46 g kg⁻¹ for −Nm and +Nm, respectively), yet increased with the higher rates of cricket frass (1.42–1.52 g kg⁻¹ for −Nm, and 1.23–1.51 g kg⁻¹ for +Nm) compared to the unamended soil (1.05 and 1.00 g kg⁻¹ for −Nm and +Nm). Cations, including K, Ca, Mg, and Na derived from cricket frass, may enhance biosynthesis and the accumulation of oxalic acid. The neem seed extract decreased the tissue’s oxalic contents regardless of soil amendments. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

12 pages, 3022 KiB

Open AccessArticle

Fertilizer Nitrogen Application for Short-Day Onion Production: From Field to Table

by Andre Luiz Biscaia Ribeiro da Silva, Camila Rodrigues, Laurel Dunn, George Cavender and Timothy Coolong

Horticulturae 2022, 8(9), 847; https://doi.org/10.3390/horticulturae8090847 - 15 Sep 2022

Cited by 3 | Viewed by 1766

Abstract

Long growing seasons, relatively shallow root system, coarse textured soils, and variability of the subtropical environmental conditions of the southeastern U.S. create challenges for nitrogen (N) fertilizer management of short-day onions. The objectives of this study were: (i) to evaluate the impact of [...] Read more.

Long growing seasons, relatively shallow root system, coarse textured soils, and variability of the subtropical environmental conditions of the southeastern U.S. create challenges for nitrogen (N) fertilizer management of short-day onions. The objectives of this study were: (i) to evaluate the impact of fertilizer N rates on the yield and bulb quality of three short-day onion cultivars grown under the subtropical conditions of the southeastern U.S., and (ii) to assess the impact of fertilizer N rate for short-day onions on consumers’ preference. Field experiments were conducted in 2019 and 2020 at the Vidalia Onion and Vegetable Research Center at the University of Georgia located in Lyons, GA, in which a two factorial experimental design of five fertilizer N rates (84, 101, 117, 134, and 151 kg of N ha⁻¹) and three short-day onion cultivars (Sweet Agent, Vidora, and Quick Start) was evaluated in a randomized complete block design. During both growing seasons, rainfall events directly impacted soil mineral N content. While soil mineral N availability increased with fertilizer N application, there was no significant difference among fertilizer N rate treatments due to rainfall distribution in both years studied, except at bulb initiation when the application of 117 kg of N ha⁻¹ sustained soil mineral N availability that maximized with the application of 128 kg of N ha⁻¹. Onion total yield averaged 37,365 kg ha⁻¹ in 2019 and 34,699 kg ha⁻¹ in 2020. In general, colossal, jumbo, and medium-sized onions represented 7%, 76%, and 17% of total yield, respectively. Jumbo-sized onions are of most interest to growers due to their high value, and the yield of jumbo-sized onions was maximized with 158 kg of N ha⁻¹ in 2019 and with 138 kg of N ha⁻¹ in 2020. Bulb bacterial rots were not impacted by fertilizer N rate treatments. Contrarily, bulb gallic acid (GAE) linearly increased and pyruvic acid quadratically increased with the application of fertilizer N rate. Ultimately, a taste panel indicated that sensory characteristics were also not affected by different rates. Overall, a fertilizer N rate application of 117 to 134 kg of N ha⁻¹ could sustain soil mineral N availability without impacting yield; however, an investigation on the timing of application should be conducted to determine a fertilizer N strategy that will promote optimum yield, bulb quality, flavor, and consumer acceptability. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 1655 KiB

Open AccessArticle

Cover Crops Increase N and P Cycling and Rice Productivity in Temperate Cropping Systems

by Rodolfo Lizcano Toledo, Cristina Lerda, Barbara Moretti, Eleonora Miniotti, Veronica Santoro, Emilia Fernandez-Ondoño, Maria Martin, Daniel Said-Pullicino, Marco Romani and Luisella Celi

Agronomy 2022, 12(9), 2193; https://doi.org/10.3390/agronomy12092193 - 15 Sep 2022

Cited by 1 | Viewed by 2136

Abstract

Cover crops can determine positive benefits on soil fertility and rice productivity, although scant attention has been devoted to evaluating the effects of hairy vetch (Vicia villosa Roth) and the incorporation of rice straw with different N fertilization levels on soil [...] Read more.

Cover crops can determine positive benefits on soil fertility and rice productivity, although scant attention has been devoted to evaluating the effects of hairy vetch (Vicia villosa Roth) and the incorporation of rice straw with different N fertilization levels on soil N and P availability and crop yields in temperate cropping systems characterized by poorly developed soils. In this study, the effects of cover crops grown before rice in a temperate mono-cropping system (NW Italy) on: (i) crop yields and yield components; (ii) apparent N fertilizer recovery and optimal level of N fertilization with hairy vetch; and (iii) temporal variation of soil available N and P forms during the hairy vetch growth and rice cropping season, have been investigated. The cultivation and incorporation of hairy vetch in the rice cropping system increased grain productivity by 12%, while reducing N mineral fertilization requirements by 33%. Combined with the incorporation of crop residues, hairy vetch provided a N and P input of 178 and 18 kg ha⁻¹, respectively, representing a readily available source for plant uptake over the whole rice cropping season, particularly under anaerobic conditions. This results in a better temporal synchronization of soil N and P availability with crop nutrient demand, leading to a better rice grain productivity and quality performance. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1969 KiB

Open AccessArticle

Spatial Changes in Glomalin-Related Soil Protein and Their Correlation with Soil Properties in the Black Soil Region of Northeast China

by Xiaoli Wang, Qingjun Cao, Wenying Yang and Xiancan Zhu

Agronomy 2022, 12(9), 2165; https://doi.org/10.3390/agronomy12092165 - 12 Sep 2022

Cited by 3 | Viewed by 1867

Abstract

Glomalin-related soil protein (GRSP), soil nutrients, and soil enzyme activities are closely related to soil fertility and land productivity, which play an important role in indicating soil quality. Little is known about the spatial variation in GRSP and its relationship with edaphic factors. [...] Read more.

Glomalin-related soil protein (GRSP), soil nutrients, and soil enzyme activities are closely related to soil fertility and land productivity, which play an important role in indicating soil quality. Little is known about the spatial variation in GRSP and its relationship with edaphic factors. Here, the spatial distribution of GRSP, soil chemical properties, and the soil enzyme activities of 0–20 cm depth farmland soil in the black soil region of northeast China were investigated, and the relationships among edaphic factors were analyzed collected from 41 sampling sites. The results indicate that GRSP, soil organic matter, total nitrogen, and acid phosphatase activities showed significant patterns of spatial variation, generally decreasing from north to south along a latitudinal gradient. Principal component analysis revealed that total GRSP (by 80.19%) and soil organic matter content (by 80.15%) were the greatest contributing factors accounting for the variations. Edaphic factors such as soil organic matter, total nitrogen, total phosphorus, and acid phosphatase were significantly positively correlated with GRSP, while urease was negatively correlated with GRSP. Mantel tests also showed that soil organic matter, total nitrogen, urease, and acid phosphatase were positively correlated with GRSP. The results reflect the soil fertility characteristics of the black soil region of northeast China and reveal the relationship among edaphic factors. These findings could be used to inform agricultural production and provide new insight into the role of GRSP in soil quality. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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9 pages, 858 KiB

Open AccessArticle

Kinetics of Phosphorus Uptake through Roots of Habanero Pepper (Capsicum chinense Jacq. cv. Mayapán)

by Carmen Yam-Chimal, Luis Ramírez-y-Avilés, Jorge Navarro-Alberto, Francisco Solorio-Sánchez, Eduardo Villanueva-Couoh and José Noh-Medina

Agriculture 2022, 12(9), 1389; https://doi.org/10.3390/agriculture12091389 - 04 Sep 2022

Viewed by 1786

Abstract

The application of enzymatic kinetics theory on the nutrition of horticultural species is scarce. I_ma_x and K_m describe the kinetics of nutrient absorption by the plant. I_max and K_m are necessary to predict phosphorus (P) uptake from soil [...] Read more.

The application of enzymatic kinetics theory on the nutrition of horticultural species is scarce. I_ma_x and K_m describe the kinetics of nutrient absorption by the plant. I_max and K_m are necessary to predict phosphorus (P) uptake from soil using mathematical models, and their estimation gives information about the efficient use of P in plants. I_max and K_m for habanero pepper (Capsicum chinense Jacq. cv. Mayapán) were determined using the modified exhaustion method. Depletion of P by the roots was obtained with 0.01, 0.125, 0.25, 0.50, and 1.00 mM P L⁻¹. P-depletion data over time were fitted to an exponential-regression model to obtain the initial P-uptake rates by the roots. Initial P-uptake rates were significantly different (p < 0.001) depending on the levels of P in the solution. I_max and K_m were predicted by iteratively fitting the initial P-absorption rates in terms of the concentration of P to the Michaelis–Menten model. The average I_max was 3.49 × 10⁻⁷ mM cm² s⁻¹ and K_m was 2.59 × 10⁻² mM P L⁻¹. These results show that the habanero pepper root can uptake 1.08 × 10⁻⁵ mg P L⁻¹ per cm² in the soil solution per second and P transporters are saturated with 2.59 × 10⁻² mM P L⁻¹. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1111 KiB

Open AccessArticle

Responses of Tobacco Growth and Development, Nitrogen Use Efficiency, Crop Yield and Economic Benefits to Smash Ridge Tillage and Nitrogen Reduction

by Bufan Zheng, Yongfeng Jing, Yidong Zou, Ruiwen Hu, Yongjun Liu, Zhipeng Xiao, Fei He, Qiyun Zhou, Xiangshen Tian, Jia Gong, Juan Li and Zhongwen Rang

Agronomy 2022, 12(9), 2097; https://doi.org/10.3390/agronomy12092097 - 02 Sep 2022

Cited by 4 | Viewed by 1855

Abstract

Long-term rotary tillage leads to thinning of the soil layer and low nitrogen use efficiency of crops, resulting in a decrease in crop yield and quality. Therefore, a new alternative method to improve nitrogen use efficiency of crops needs to be found urgently. [...] Read more.

Long-term rotary tillage leads to thinning of the soil layer and low nitrogen use efficiency of crops, resulting in a decrease in crop yield and quality. Therefore, a new alternative method to improve nitrogen use efficiency of crops needs to be found urgently. Here, we analyzed the effects of a new smash ridge tillage method combined with reduced nitrogen application on tobacco growth and development, and nitrogen use efficiency and its economic benefits. The results showed that, compared with conventional tillage and nitrogen application of 180 kg N ha⁻¹, smash ridge tillage and a 30% reduction in nitrogen rate resulted in greater root length density, more primary lateral roots and greater rooting depth in the subsoil. It is also beneficial to maintain a high level of biomass and nitrogen accumulation in the later growth period, increasing the output value of tobacco by CNY 1588.35 ha⁻¹ and reducing the cost by CNY 974.1 ha⁻¹ on average in two years. In conclusion, our study highlights the economic benefits of smash ridge tillage and nitrogen reduction for tobacco growth and development, and considers them an effective method for improving agricultural productivity and nitrogen use efficiency. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1549 KiB

Open AccessArticle

Enhancing Water Use Efficiency and Yield of Pomegranate Crop by Using Fish Drainage Water with Bio-Fertilizer under Drip Irrigation System

by M. A. M. Moursy, Amro Negm, H. G. Ghanem and Kamal I. Wasfy

Agriculture 2022, 12(9), 1376; https://doi.org/10.3390/agriculture12091376 - 02 Sep 2022

Cited by 1 | Viewed by 1996

Abstract

Fish drainage water is a non-conventional water resource that can be exploited for irrigation due to its constituents of beneficial nutrients, signifying it as environment-friendly bio-fertilizers. Limited water resources, the elevated cost of mineral fertilizers hazards as well as attaining healthy food are [...] Read more.

Fish drainage water is a non-conventional water resource that can be exploited for irrigation due to its constituents of beneficial nutrients, signifying it as environment-friendly bio-fertilizers. Limited water resources, the elevated cost of mineral fertilizers hazards as well as attaining healthy food are of paramount significance in the agriculture sector in Egypt. The utilization of bio-fertilizers is an avenue to fulfil agricultural sustainability, production of clean crops and preservation of the soil from the accumulation of heavy metals and chemicals. Hence, this study aims to find non-conventional alternative water resources to be used for irrigation of pomegranate fruit yield. Two resources of water were utilized, and three types of bio-fertilizers were applied. Results showed that, fish drainage water increased the total yield (kg/fed) by 25.2% as compared to freshwater. Chicken manure increased the total yield (kg/fed) by 22.37 and 11.89% in comparison with cattle and compost organic fertilizer under fish drainage water, respectively. The use of chicken manure yielded the highest net return (2420.79US $/fed), while compost and cattle dung were found to be (2123.52US $/fed) and (1721.66US $/fed), respectively, under using fish drainage water. The study showed that the use of fish drainage water as an organic resource would be an alternative to commercial fertilizers, which could reduce the total cost and thus increase the net profit and yield. Less dependency of commercial fertilizer would have an impact on reducing the emissions of CO₂ mitigating global warming. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 1026 KiB

Open AccessArticle

Application of Homemade Organic Fertilizer for Improving Quality of Apple Fruit, Soil Physicochemical Characteristics, and Microbial Diversity

by Xiuzhang Wang, Qi Bao, Guotao Sun and Jianming Li

Agronomy 2022, 12(9), 2055; https://doi.org/10.3390/agronomy12092055 - 29 Aug 2022

Cited by 4 | Viewed by 3078

Abstract

Application of the organic fertilizers can improve soil properties and agricultural product quality, while the in-depth effect of organic fertilizer needs further exploration. In this study, the apple fruit (Malus pumila Mill.) quality, soil physicochemical characteristics, and microbial community under different fertilizers [...] Read more.

Application of the organic fertilizers can improve soil properties and agricultural product quality, while the in-depth effect of organic fertilizer needs further exploration. In this study, the apple fruit (Malus pumila Mill.) quality, soil physicochemical characteristics, and microbial community under different fertilizers including control without fertilizer (CK), composted manure (CM), biogas slurry (BS), and chemical fertilizer (CF) were systematically investigated, and each treatment was repeated three times in completely random block plots with equal NPK content of fertilizer applied in each treatment. The CM treated apple fruit were observed with the best vertical diameter (78.72 ± 4.32 mm), transverse diameter (87.51 ± 1.3 mm), and color index (L* = 55.48 ± 5.48, b* = 18.96 ± 1.86). Meanwhile, the CM and BS treated apple fruit had higher flesh firmness than that of CK and CF treatment, implying that the organic fertilization can improve the storability and crispy taste apple fruit. Furthermore, the total sugars, essential amino acid, crude protein, total acids, and soluble solid contents of apple fruit were also significantly improved by using CM and BS fertilizer due to the resulting higher N, P, and organics content in soil. The application of organic fertilizer also dramatically enhanced the bacterial and fungi diversity, which may contribute to better soil respiration. The results obtained in this study reveals the insight effect of organic fertilizer on improvement of fruit quality and soil health and can supply technical assistance to organic cultivation of apple. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 2661 KiB

Open AccessArticle

Nodule Formation and Nitrogen Use Efficiency Are Important for Soybean to Adapt to Water and P Deficit Conditions

by Yi Jin, Jin He, Yonghe Zhu and Kadambot H. M. Siddique

Agriculture 2022, 12(9), 1326; https://doi.org/10.3390/agriculture12091326 - 28 Aug 2022

Cited by 5 | Viewed by 2252

Abstract

Drought stress and phosphorus (P) deficit decrease soybean P and nitrogen (N) accumulation, which limits soybean productivity. Therefore, soybean traits related to N and P uptake and/or their efficient utilization are important for soybean adaptation to P- and water-deficit conditions. We hypothesize that [...] Read more.

Drought stress and phosphorus (P) deficit decrease soybean P and nitrogen (N) accumulation, which limits soybean productivity. Therefore, soybean traits related to N and P uptake and/or their efficient utilization are important for soybean adaptation to P- and water-deficit conditions. We hypothesize that increasing soybean nodulation to enhance N and P uptake, and/or improving N and P use efficiency (PUE and NUE) are important for the adaptation of soybean to drought and low P conditions. To test this hypothesis, we selected four genotypes with different nodule dry weight (DW) and yield performance for a pot experiment under two water treatments [well-watered (WW) and cycle water stress (WS)] and three P levels [0 (P0, low), 60 (P60, mid), and 120 (P120, high) mg P kg⁻¹ dry soil on top 40 cm]. Our study showed that P deficit and water stress significantly decreased soybean P and N accumulation, which limited seed yield under both WS and WW conditions. P addition increased soybean nodule dry weight (DW), thus increasing N and P uptake. Increasing nodule DW required high water use, and while there was no relationship found between nodule DW and yield under WS, a positive relationship under WW was shown. Partitioning more dry matter to seed could improve NUE and PUE. P addition did not change soybean NUE, which is important to yield determination under WS and P0 but has no effect on yield under WW. We conclude that increasing nodule formation improved soybean N and P uptake, which diminished the yield loss under WS and improved yield performance under WW. While high NUE reflects efficient utilization of N, which can improve yield under drought stress and low P availability, and does not impair the yield under WW. We propose that NUE and nodules are important traits for breeders to improve the tolerance to water- and P-deficit conditions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1495 KiB

Open AccessArticle

Evaluation of Soil Quality in a Composite Pecan Orchard Agroforestry System Based on the Smallest Data Set

by Cheng Huang, Zhaocheng Wang, Xiaoliang Ren, Xiaomin Ma, Mengyu Zhou, Xiang Ge, Hua Liu and Songling Fu

Sustainability 2022, 14(17), 10665; https://doi.org/10.3390/su141710665 - 26 Aug 2022

Cited by 6 | Viewed by 1377

Abstract

Agroforestry not only takes into account the use of land for forestry and agriculture but can also improve the efficacy of utilized above- and belowground resources, which have always garnered widespread attention. The objective of this study is to evaluate the quality of [...] Read more.

Agroforestry not only takes into account the use of land for forestry and agriculture but can also improve the efficacy of utilized above- and belowground resources, which have always garnered widespread attention. The objective of this study is to evaluate the quality of pecan orchard soil following the implementation of agroforestry. Consequently, 15 indices were selected for a principal component analysis (PCA), which was then combined with the norm value of each index and the correlation coefficients between indices to establish a minimum data set (MDS). A comprehensive index model was used to calculate the soil quality index (SQI) of the total data set (TDS) and MDS (SQI-TDS and SQI-MDS, respectively), and a linear regression of the two was performed. The results revealed that the MDS indices for the evaluation of soil fertility included the pH, electrical conductivity value (EC), bulk density (BD), available potassium (AK), total nitrogen (TN), magnesium (Mg), and the index screening and filtering rates attained 60%. The Soil Quality Index (SQI-MDS) of the four planting patterns, sorted from largest to smallest, were: PPS (0.573) > PPH (0.519) > PPL (0.355) > CK (0.315). BD and AK were the main factors that affected the quality of hickory orchard soils. The agroforestry composite system improved the availability of nutrients and soil quality. Thus, the promotion of understory intercropping and appropriate increases in potassium fertilizers for plantations are recommended. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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8 pages, 256 KiB

Open AccessArticle

Application of New-Generation Growth Regulators and Topdressing Nitrogen Fertilizers Increases Improver Winter Wheat Yield and Grain Quality in South Russia

by Yurii Pleskachiov, Sergey Voronov, Serazhutdin Kurbanov, Francess Sia Saquee and Meisam Zargar

Agriculture 2022, 12(9), 1310; https://doi.org/10.3390/agriculture12091310 - 25 Aug 2022

Cited by 2 | Viewed by 2326

Abstract

The need for effective nutrient management is crucial for optimizing wheat production and increasing the plant’s ability to tolerate different environmental stresses. In this study, we assessed the influence of new-generation PGRs and foliar topdressing nitrogen fertilizer and their interactive effects on wheat [...] Read more.

The need for effective nutrient management is crucial for optimizing wheat production and increasing the plant’s ability to tolerate different environmental stresses. In this study, we assessed the influence of new-generation PGRs and foliar topdressing nitrogen fertilizer and their interactive effects on wheat yield and quality parameters of grain and flour. A three-year field experiment was conducted on the dark chestnut soil of the Rostov region. We estimated the effect of foliar topdressing liquid nitrogen fertilizer on consumption rates of N32 (N32), N64 (N32 + N32), and N96 (N32 + N32 + N32), as well as new-generation plant growth regulators (PGRs), namely, Zirkon, Silk, and Albit, on the productivity and grain quality of winter wheat Tarasovskaya 70. The results of the experiments indicate that the highest average grain yield over three years was 5.34 t/ha⁻¹ with the application of N96 (N32 + N32 + N32) and Albit PGR. In 2020, due to favorable weather conditions, the greatest grain yield was attained at 6.27 t/ha⁻¹ for N96 (N32 + N32 + N32) and Albit PGR. The highest grain quality with the greatest gluten content >28% was obtained when N96 (N32 + N32 + N32) and PGRs were applied. According to the results, using N96 (N32 + N32 + N32) and PGRs made it possible to obtain “valuable” grain in terms of quality, which is suitable for the production of premium flour. The beneficial interactive effects of N application rates and PGRs on winter wheat yield and quality parameters are worthy of further investigation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

10 pages, 1773 KiB

Open AccessArticle

From Ground to Grain: Tracing Phosphorus and Potassium in Flooded Rice Cultivar Grown on Histosols

by Naba R. Amgain, Yuchuan Fan, Matthew T. VanWeelden, Abul Rabbany and Jehangir H. Bhadha

Agriculture 2022, 12(8), 1250; https://doi.org/10.3390/agriculture12081250 - 18 Aug 2022

Viewed by 1864

Abstract

To trace the phosphorus (P) and potassium (K) content in flooded rice (Oryza sativa L), 14 rice cultivars commonly grown in the Southern United States were evaluated for their P and K concentration in tissue and grain. Field experiments were conducted at [...] Read more.

To trace the phosphorus (P) and potassium (K) content in flooded rice (Oryza sativa L), 14 rice cultivars commonly grown in the Southern United States were evaluated for their P and K concentration in tissue and grain. Field experiments were conducted at two locations in Everglades Agriculture Area (EAA), where flooded rice was cultivated on organic Histosols. Soil pH and Mehlich-3 phosphorus (M3P) were significantly different between locations. At Site I, soil pH, M3P, and Mehlich-3 potassium (M3K) varied in the range of 6.8–7.1, 21.4–36.4 mg kg⁻¹, and 53.9–151.0 mg kg⁻¹, respectively. At Site II, soil pH, M3P and M3K varied in the range of 6.9–7.3, 11.2–20.5 mg kg⁻¹, and 64.8–104.1 mg kg⁻¹, respectively. Stem potassium was the only measured parameter that was significantly different among rice cultivars at both sites. At Site I and Site II, stem K ranged from 14.2–26.6 mg kg⁻¹ and 10.4–19.4 mg kg⁻¹, respectively. No significant difference in yield among cultivars was observed at Site I, whereas Site II had a significant difference in yield among cultivars. At Site I and Site II, yields ranged from 3745–7587 kg ha⁻¹ and 2627–6406 kg ha⁻¹, respectively. None of the cultivars ranked consistently in the same top and bottom position for each measured parameter. Total phosphorus (TP) concentration was highest in grain, whereas total potassium (TK) concentration was highest in the stem. Results suggest incorporation of rice stem into the soil could potentially add fertilizer back to the soil which helps in fertility management. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 1907 KiB

Open AccessArticle

Comparative Approach on the Effects of Soil Amendments and Controlled-Release Fertilizer Application on the Growth, Nutrient Uptake, Physiological Performance and Fruit Quality of Pepper (Capsicum annuum L.) Plants

by Theocharis Chatzistathis, Georgios Tsaniklidis, Athanasios Papaioannou, Anastasia Giannakoula and Athanasios Koukounaras

Agronomy 2022, 12(8), 1935; https://doi.org/10.3390/agronomy12081935 - 17 Aug 2022

Cited by 3 | Viewed by 1886

Abstract

Under the economic pressure from the increase of fertilizers’ prices due to the recent energy crisis, more efforts are needed to search for alternative and cheaper sources of nutrients for crops. The purpose of our study was to compare the effects of manure [...] Read more.

Under the economic pressure from the increase of fertilizers’ prices due to the recent energy crisis, more efforts are needed to search for alternative and cheaper sources of nutrients for crops. The purpose of our study was to compare the effects of manure and inorganic amendments’ application to those derived from the application of a controlled-release fertilizer (CRF) on the growth, nutrition, physiology and fruit quality of pepper plants. For that reason, zeolite (ZEO) and vermiculite (VER) were applied either independently, or in combination between them, or with manure (MAN), in a pot experiment. Insignificant differences for plant growth among the treatments were recorded, while higher foliar N, Mg and Mn concentrations were determined in CRF. In contrast, a significantly higher K uptake was recorded in the ZEO and VER + ZEO treatments; the highest leaf P levels (0.47 and 0.44% D.W.) were recorded in the MAN + VER and ZEO treatments, respectively. The optimum photosynthetic II (PSII) performance was observed in the VER and in the MAN + ZEO (based on the performance index—PI) treatments. The highest stomata opening was found in the CRF treatment, while the photosynthetic rate of pepper plants showed its maximum values both in the CRF and VER treatments. Finally, fruit quality (as indicated by total soluble solids, total phenols and antioxidant activity—FRAP) was significantly influenced by treatment. In conclusion, significant differences in the growth, nutrition and physiological performance of pepper plants between soil amendments’ application (inorganic, such as zeolite and vermiculite, and organic, such as manures) and CRF application were recorded; thus, these amendments should be more thoroughly studied in future projects to investigate if they could partially decrease high inorganic fertilization rates in Capsicum annuum L. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 4533 KiB

Open AccessArticle

Soil Available Nitrogen and Yield Effect under Different Combinations of Urease/Nitrate Inhibitor in Wheat/Maize Rotation System

by Xiumin Cui, Jingquan Wang, Jiahui Wang, Yun Li, Yanhong Lou, Yuping Zhuge and Yuxiu Dong

Agronomy 2022, 12(8), 1888; https://doi.org/10.3390/agronomy12081888 - 11 Aug 2022

Cited by 2 | Viewed by 1855

Abstract

In a wheat/maize rotation system, nitrogen (N) accounts for a large proportion of basal fertilizer, but soil N loss and the resulting environmental risk simultaneously exist worldwide. This study applied different urease/nitrification inhibitors together with basal fertilizers and investigated their effects on soil [...] Read more.

In a wheat/maize rotation system, nitrogen (N) accounts for a large proportion of basal fertilizer, but soil N loss and the resulting environmental risk simultaneously exist worldwide. This study applied different urease/nitrification inhibitors together with basal fertilizers and investigated their effects on soil N level and grain yield. Six N stabilizing combinations consisted of two urease inhibitors (HQ and NBPT) and three nitrification inhibitors (DCD, DMPP, and Nitrapyrin). The treatments supplied with urease/nitrification inhibitors reduced, to some degree, the conversion rate of

{N H}_{4}^{+}

into

{N O}_{3}^{-}

, and kept

{N H}_{4}^{+}

content higher in surface soils for a longer time. Compared to CK, A1 treatment supplied with 1.5% HQ + 4% DCD well-maintained the levels of soil alkali-hydrolyzable N and

{N H}_{4}^{+}

. For example, alkali-hydrolyzable N and

{N H}_{4}^{+}

contents at 0–20 cm soil layer under A1 were increased by 8.59–41.6% and 8.15–14.5% more than CK, respectively. Based on the entire growth period of wheat and maize rotation, urease/nitrification inhibitors improved soil available N in surface soils but did not prevent

{N H}_{4}^{+}

and

{N O}_{3}^{-}

leaching, especially in the intensive rainfall season. The combinations of HQ and DCD or Nitrapyrin significantly enhanced crop yield. Specifically, crop yields under A1 and A3 (1.5% HQ + 0.25% Nitrapyrin) were 16.3% and 14.3% higher than CK, respectively. The N stabilizing combinations also promoted N intake and transport at every growth stage. The maximum N accumulation was increased by 27% under A1, when compared to CK. The treatments supplied with urease/nitrification inhibitors also achieved higher apparent N recovery efficiency, N agronomic efficiency, and N partial factor productivity. Consequently, the combinations of urease/nitrification inhibitors could improve N availability at 0–40 cm soil layer, which in turn improved N use efficiency of wheat and maize. The results suggested that the two urease/nitrification inhibitor combinations, 1.5% HQ + 4% DCD (A1) and 1.5% HQ + 0.25% Nitrapyrin (A3), were optimal N stabilizing agents and worthy of further study. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 2852 KiB

Open AccessArticle

Cowpea Growth and Nitrogen Fixation Performance under Different Mulch Treatments

by Florence M. Masete, Lawrence Munjonji, Kingsley K. Ayisi and Moshibudi P. Mopape-Mabapa

Agriculture 2022, 12(8), 1144; https://doi.org/10.3390/agriculture12081144 - 02 Aug 2022

Cited by 2 | Viewed by 1956

Abstract

Mulching is regarded as the most important of the three conservation agriculture principles in increasing crop yield in the short term. Thus, the main objective of this study was to investigate the impact of mulch type and mulch application rate on biological nitrogen [...] Read more.

Mulching is regarded as the most important of the three conservation agriculture principles in increasing crop yield in the short term. Thus, the main objective of this study was to investigate the impact of mulch type and mulch application rate on biological nitrogen fixation (BNF), physiological and yield responses of cowpea. A multi-locational (two locations) and multi-seasonal (two seasons) study was carried out under rainfed conditions in the Limpopo Province of South Africa. Three mulch types (Moringa oleifera stems; Moringa oleifera leaves and twigs; and Vachellia karroo leaves and stems) were uniformly spread on the surface at four rates (0, 3, 6, 9 t/ha). The application of mulches, regardless of the rate and type, improved cowpea chlorophyll content and agronomic parameters, such as stem diameter and plant height. Grain yield at Syferkuil responded to the mulching effect in both seasons, while at Ofcolaco, differences were only observed in one of the seasons. Cowpea under control discriminated against ¹⁵N more than under mulched treatments, resulting in more than 70% of the nitrogen being derived from air compared to 50% in mulched plots. This study demonstrated that organic surface mulches improved the physiological responses of cowpea and that organic surface mulches with a lower C:N ratio significantly reduced BNF. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 1569 KiB

Open AccessArticle

Optimizing Phytochemical and Physiological Characteristics of Balangu (Lallemantia iberica) by Foliar Application of Chitosan Nanoparticles and Myco-Root Inoculation under Water Supply Restrictions

by Abdollah Javanmard, Mahsa Ashrafi, Mohammad Reza Morshedloo, Mostafa Amani Machiani, Farzad Rasouli and Filippo Maggi

Horticulturae 2022, 8(8), 695; https://doi.org/10.3390/horticulturae8080695 - 01 Aug 2022

Cited by 12 | Viewed by 2369

Abstract

Balangu is a medicinal plant used in the Iranian traditional medicine to treat nervous, hepatic and renal diseases. To determine the effects of Myco-Root biofertilizer and chitosan nanoparticles (Cs-NPs) on the physiological and biochemical properties of balangu (Lallemantia iberica (M.Bieb.) Fisch. & [...] Read more.

Balangu is a medicinal plant used in the Iranian traditional medicine to treat nervous, hepatic and renal diseases. To determine the effects of Myco-Root biofertilizer and chitosan nanoparticles (Cs-NPs) on the physiological and biochemical properties of balangu (Lallemantia iberica (M.Bieb.) Fisch. & C.A.Mey.) under different irrigation levels, an experiment was laid out as a factorial based on completely randomized design (CRD) with twelve treatments and three replications. The first factor was represented by different irrigation regimes, including no water deficit (90% FC), mild water deficit (60% FC) and severe water deficit (30% FC); the second factor included control (no Myco-Root and Cs-NPs), inoculation with Myco-Root biofertilizer, foliar application of chitosan nanoparticles (Cs-NPs) and co-application of Cs-NPs along with Myco-Root. The results showed that the highest fresh and dry weight, chlorophyll and carotenoid content, chlorophyll index (SPAD) and fluorescence indices were obtained in 90% FC treated with Cs-NPs+ Myco-Root. In addition, the maximum activity of superoxide dismutase (SOD), ascorbate peroxidase (APX) and peroxidase (POX) was achieved in 60% FC with application of Cs-NPs+ Myco-Root. Moreover, the maximum essential oil content (1.43%) and yield (0.25 g pot⁻¹) were recorded in 60% FC following the application of Cs-NPs+ Myco-Root. Chemical analysis of essential oil showed that germacrene D (31.22–39.77%), (E)-caryophyllene (16.28–19.82%), bicyclogermacrene (7.1–9.22%) and caryophyllene oxide (3.85–6.96%) were the major volatile constituents of balangu. Interestingly, the maximum contents of germacrene D and (E)-caryophyllene were recorded in 60% FC after the application of Cs-NPs+ Myco-Root. Overall, it can be concluded that co-application of Cs-NPs+ Myco-Root could be a sustainable and eco-friendly strategy for improving the essential oil quantity and quality, as well as physiological characteristics, of balangu under water deficit conditions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1351 KiB

Open AccessEditor’s ChoiceArticle

Compost Composition and Application Rate Have a Greater Impact on Spinach Yield and Soil Fertility Benefits Than Feedstock Origin

by Alicia J. Kelley, David N. Campbell, Ann C. Wilkie and Gabriel Maltais-Landry

Horticulturae 2022, 8(8), 688; https://doi.org/10.3390/horticulturae8080688 - 29 Jul 2022

Cited by 6 | Viewed by 2164

Abstract

Rapid urbanization results in the accumulation of food wastes that can be composted and diverted from landfills. Previous lab incubations demonstrated that food-based composts can increase soil N relative to manure-based composts, but these benefits were not tested within a crop system. We [...] Read more.

Rapid urbanization results in the accumulation of food wastes that can be composted and diverted from landfills. Previous lab incubations demonstrated that food-based composts can increase soil N relative to manure-based composts, but these benefits were not tested within a crop system. We assessed soil fertility and yield of spinach (Spinacia oleracea L.) grown in two different soils in a greenhouse, comparing two food- and two manure-based composts added at the recommended N rate (101 kg N ha⁻¹). We quantified soil N mineralization and resin-extractable phosphorus, spinach biomass (root and shoot), and crop nutrient concentrations and accumulation. Nitrogen mineralization generally peaked four weeks after application, and one food-based compost (but no manure-based composts) increased soil phosphorus at harvest compared to an unamended control. One manure-based compost and one food-based compost produced a higher yield and greater nitrogen, phosphorus, and potassium accumulation than the unamended control, whereas only the food-based compost increased spinach phosphorus and potassium concentrations. There was a positive relationship between yield and compost inputs of potassium and plant-available nitrogen (especially nitrate), suggesting that potassium inputs may also explain differences observed among composts. Our results suggest that food-based compost provides more nutrients than composts made from cow manure fiber. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 1364 KiB

Open AccessArticle

Dry-Aggregate Stability and Soil Nutrients Responses to Reapplication of Biochar and Organic/Inorganic Fertilizers in Urban Vegetable Production

by Chinyere Blessing Okebalama and Bernd Marschner

Agronomy 2022, 12(8), 1782; https://doi.org/10.3390/agronomy12081782 - 28 Jul 2022

Cited by 3 | Viewed by 1528

Abstract

Background: Knowledge of the responses of soil aggregates to various fertilization practices can contribute to sustainable soil management in urban vegetable agriculture. Aims: The study assessed the soil fertility, dry aggregate stability, and aggregate total carbon (TC) and nitrogen (TN) retention after the [...] Read more.

Background: Knowledge of the responses of soil aggregates to various fertilization practices can contribute to sustainable soil management in urban vegetable agriculture. Aims: The study assessed the soil fertility, dry aggregate stability, and aggregate total carbon (TC) and nitrogen (TN) retention after the reapplication of biochar, and organic/inorganic fertilizers. Methods: Four replicates of ecological sanitation (ECOSAN) manure, NPK fertilizer, corncob biochar (CCB), and CCB, combined with urea and cattle manure (UCF), were established in a randomized complete block design. Results: The application of ECOSAN increased the soil pH and also resulted in significant accumulation of available phosphorus (P), calcium (Ca), and magnesium (Mg). Compared to CCB treatment, UCF + CCB produced significant increases in the TC, TN, P, Ca, and Mg concentrations by 53, 140, 227, 27, and 78%, respectively, and additionally increased the 4.75–2.00 mm large macroaggregates and mean weight diameter. The total carbon increased significantly in microaggregates (>0.25 mm); macroaggregates (4.75–0.25 mm); and in the micro- and macroaggregate fractions of the ECOSAN, CCB, and UCF + CCB treatments, respectively. More so, the TN in micro- and macroaggregates was increased maximally by UCF + CCB and minimally by the CCB treatment. Conclusions: The reapplication of CCB had limited potential for carbon sequestration in soil aggregates, but its combination with UCF better reflects carbon and nitrogen stabilization in micro- and macro- aggregates, with greater potential in large macroaggregates. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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9 pages, 625 KiB

Open AccessCommunication

Grain Zinc and Yield Responses of Two Rice Varieties to Zinc Biofortification and Water Management

by Kankunlanach Khampuang, Bernard Dell, Nanthana Chaiwong, Sithisavet Lordkaew, Hatem Rouached and Chanakan Prom-u-thai

Sustainability 2022, 14(14), 8838; https://doi.org/10.3390/su14148838 - 19 Jul 2022

Cited by 1 | Viewed by 1534

Abstract

Zinc (Zn) biofortification can improve grain yield and nutritional quality in rice, but its effectiveness is subject to agronomic practices and other factors. In a previous study, the application of Zn to soil enhanced grain Zn in lowland rice in well-drained and waterlogged [...] Read more.

Zinc (Zn) biofortification can improve grain yield and nutritional quality in rice, but its effectiveness is subject to agronomic practices and other factors. In a previous study, the application of Zn to soil enhanced grain Zn in lowland rice in well-drained and waterlogged soil, whereas grain Zn in upland rice increased only in well-drained soil. This new study explores the hypothesis that the application of foliar Zn can enhance grain Zn in upland and lowland rice grown under waterlogged and well-drained conditions. Two rice varieties, CNT1 (wetland rice) and KH CMU (upland rice) were grown in containers in waterlogged or well-drained soil with three Zn treatments (no Zn, soil Zn and foliar Zn). For the soil Zn treatment, 50 kg ZnSO₄ ha⁻¹ was applied to the soil before transplanting. For the foliar treatment, 0.5% ZnSO₄ (equivalent to 900 L ha⁻¹) was applied at booting and repeated at flowering and milky growth stages. Grain yield in CNT1 was 15.9% higher in the waterlogged than in the well-drained plants, but the water regime had no effect on grain yield in KH CMU. Grain Zn concentration in CNT1 increased from 19.5% to 32.6% above the no Zn control when plants were applied with soil or foliar Zn. In KH CMU, there was an interaction between the water regime and Zn treatment. Application of foliar Zn increased grain Zn by 44.6% in well-drained and 14.7% in waterlogged soil. The results indicate strong interaction effects between variety, water regime and Zn fertilizer application on Zn biofortification in rice. Thus, the selection of rice varieties and growing conditions should be considered in order for producers to achieve desirable outcomes from high grain Zn concentrations. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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8 pages, 263 KiB

Open AccessArticle

Influence of Vermicompost Application on the Growth of Vinca rosea valiant, Pelargonium peltatum L. and Pegasus patio rose

by Aslihan Esringü, Metin Turan, Svetlana Sushkova, Tatiana Minkina, Vishnu D. Rajput, Alexey Glinushkin and Valery Kalinitchenko

Horticulturae 2022, 8(6), 534; https://doi.org/10.3390/horticulturae8060534 - 16 Jun 2022

Cited by 5 | Viewed by 2066

Abstract

Vermicompost (VC) is a nutrient-rich material that is mixed with soil, and it is used in this study. Four different environments were created such as control (Soil:VC:100–0%), mix one (Soil:VC:70–30% w/w), mix two (Soil:VC:50–50% w/w), and mix [...] Read more.

Vermicompost (VC) is a nutrient-rich material that is mixed with soil, and it is used in this study. Four different environments were created such as control (Soil:VC:100–0%), mix one (Soil:VC:70–30% w/w), mix two (Soil:VC:50–50% w/w), and mix three (Soil:VC:40:60% w/w), and three well-developed roses (Vinca rosea valiant, Pelargonium peltatum, Pegasus patio) seedlings were transferred to individual pots. Plant growth parameters, i.e., the number of flowers, plant height, stem diameter, chlorophyll reading value, fresh flower weight, and flower dry weight height, were compared with respect to control seedlings. The improvement in the number of flowers, plant height, stem diameter, chlorophyll reading value, fresh flower weight, and flower dry weight height by 264, 71, 58, 255, and 193% for Vinca rosea valiant rosea, 138, 12, 160, 13, 55 and 112% for P. patio rose, and 50, 14, 23, 8, 61, and 41% for P. peltatum, respectively, grown in soil mixed with VC as compared to control. As a result of the research, the optimum growth parameter values and chlorophyll Meter SPAD values were obtained from the mix-three mediums for all three roses species. These results showed that 40% soil and 60% VC application could be proposed as the most effective medium in ornamental plant production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

13 pages, 1807 KiB

Open AccessArticle

Estimation of Cotton Nutrient Uptake Based on the QUEFTS Model in Xinjiang

by Halihashi Yibati, Yan Zhang, Qingjun Li, Xingpeng Xu and Ping He

Agronomy 2022, 12(6), 1427; https://doi.org/10.3390/agronomy12061427 - 14 Jun 2022

Cited by 4 | Viewed by 2029

Abstract

The Xinjiang cotton-producing region is the main cotton-growing region in China; however, the combination of excessive application but low utilization of fertilizers has restricted its agricultural development. Estimating the balanced nutrient requirements for cotton is essential to increase its yield and nutrient use [...] Read more.

The Xinjiang cotton-producing region is the main cotton-growing region in China; however, the combination of excessive application but low utilization of fertilizers has restricted its agricultural development. Estimating the balanced nutrient requirements for cotton is essential to increase its yield and nutrient use efficiency. The results from 372 field experiments performed between 1996 and 2019 were used to build a QUEFTS (quantitative evaluation of the fertility of tropical soils) model to investigate relationships between cotton seed yield and nutrient accumulation, with the data from 2017 to 2020 used to validate the model. The results demonstrated that the QUEFTS model predicted a linear relationship between target yield and nutrient uptake until the target yield reached about 60–70% of the potential yield. To produce 1000 kg of seed cotton, 28.3 kg N, 6.1 kg P, and 29.6 kg K were required for cotton, and the corresponding ratio of N, P, and K was 4.64:1:4.85. The corresponding internal efficiencies (IEs) for N, P, and K were 35.4, 163.2, and 33.7 kg/kg, respectively. Field validation indicated that the QUEFTS model could be used to estimate nutrient uptake at a targeted yield and contribute to developing a fertilizer recommendation strategy for Xinjiang cotton production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1885 KiB

Open AccessArticle

Soybean Yield Response of Biochar-Regulated Soil Properties and Root Growth Strategy

by Di Wu, Weiming Zhang, Liqun Xiu, Yuanyuan Sun, Wenqi Gu, Yuning Wang, Honggui Zhang and Wenfu Chen

Agronomy 2022, 12(6), 1412; https://doi.org/10.3390/agronomy12061412 - 12 Jun 2022

Cited by 13 | Viewed by 3425

Abstract

Continuous cropping obstacles limit soybean production. Biochar is beneficial for soybean growth, but it is unclear whether biochar performs a sustainable role in continuous cropping. To further explore the effects of biochar on soil properties and soybean growth, a ceramic Wagner pot-simulated field [...] Read more.

Continuous cropping obstacles limit soybean production. Biochar is beneficial for soybean growth, but it is unclear whether biochar performs a sustainable role in continuous cropping. To further explore the effects of biochar on soil properties and soybean growth, a ceramic Wagner pot-simulated field experiment was conducted with biochar at different doses (12, 24, and 48 t·ha⁻¹) over a period of 3 years, no fertilizer, no biochar (CK) and fertilizer (F)treatments were used for comparison. The results showed that biochar significantly reduced soil bulk and improved the rhizosphere soil pH, available nutrients (N, K), and total nutrients (C, N, P, and K) compared with CK and F. Moreover, the soybean root length, surface area, volume, and exudates increased with biochar amendment. In particular, biochar significantly increased the nodule number, dry weight, and nitrogenase activity of soybean. Furthermore, biochar promoted soybean growth and increased soybean yield. In general, we found that the soybean yield increased with biochar and that biochar had a positive, sustainable effect on soil properties and soybean root growth, providing a new cultivation measure for soil health and soybean production in continuous cropping, which is very important for increasing soybean productivity to break the limitations of soybean traditional continuous cultivation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 3061 KiB

Open AccessArticle

Decreased Leaf Potassium Content Affects the Chemical Composition of Must for Sparkling Wine Production

by Ana Peršurić Palčić, Ana Jeromel, Marija Pecina, Igor Palčić, David Gluhić, Marko Petek and Mirjana Herak Ćustić

Horticulturae 2022, 8(6), 512; https://doi.org/10.3390/horticulturae8060512 - 10 Jun 2022

Cited by 1 | Viewed by 1518

Abstract

The must used to make sparkling wine has a low pH value and moderate sugar content, and its potassium content can have a strong influence. An excess of potassium often leads to an insufficient supply of magnesium, since potassium has a strong antagonistic [...] Read more.

The must used to make sparkling wine has a low pH value and moderate sugar content, and its potassium content can have a strong influence. An excess of potassium often leads to an insufficient supply of magnesium, since potassium has a strong antagonistic effect on magnesium, and, consequently, to poorer photosynthesis and a poorer quality of the must. The aim of this study was to determine whether the application of foliar fertilizers based on magnesium, phosphorus, and amino acids could reduce leaf potassium content, affecting the reductions in sugar content and pH value and increasing the total acidity of the must. A fertilizer trial with three replicates was conducted on the cultivar Istrian Malvasia (TCtrl—NPK, TMg—NPK + Agromag (6% MgO), TMgP—NPK + Agromag + Fosforo (30% P₂O₅) i TMgPBS—NPK + Agromag + Fosforo + Bio Prot) in a random complete block design. The NPK fertilizer was applied in the autumn. Foliar fertilization was applied three times during the growing season (31 May, 7 July, and 22 August 2014), and leaf samples were collected for leaf analysis before each application. The results show that foliar fertilization significantly reduced leaf potassium content, especially when treated with magnesium alone (treatment TMg). In addition, foliar fertilization significantly lowered the pH and increased the sugar content of the must. The results obtained in this research give a scientific contribution to the creation of fertilizer treatments for vines with a positive effect on the basic chemical composition of the base wine and provide a good basis for further research in reducing the use of certain enological practices during production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 765 KiB

Open AccessArticle

Preharvest Foliar Applications of Citric Acid, Gibberellic Acid and Humic Acid Improve Growth and Fruit Quality of ‘Le Conte’ Pear (Pyrus communis L.)

by Walid F. A. Mosa, Nagwa A. Abd EL-Megeed, Muhammad Moaaz Ali, Hesham S. Abada, Hayssam M. Ali, Manzer H. Siddiqui and Lidia Sas-Paszt

Horticulturae 2022, 8(6), 507; https://doi.org/10.3390/horticulturae8060507 - 08 Jun 2022

Cited by 9 | Viewed by 2995

Abstract

A two-year (2020-21) study was conducted to investigate the possibility of relying of ten-years old pear trees grown on sandy loam soil irrigated by drip on citric acid (CA), gibberellic acid (GA₃) and humic acid (HA). The CA was applied at [...] Read more.

A two-year (2020-21) study was conducted to investigate the possibility of relying of ten-years old pear trees grown on sandy loam soil irrigated by drip on citric acid (CA), gibberellic acid (GA₃) and humic acid (HA). The CA was applied at the concentrations of 500, 1000 and 1500 ppm, GA₃ at 50, 100 and 150 ppm and HA at 3, 4 and 5%, whereas water spray was used as the control. The results of our study proved that CA, GA₃ and HA improved the shoot length, shoot thickness, leaf area and leaf chlorophyll of pear as compared with the control. Moreover, they also positively increased the fruit set percentage and final yield of ‘Le Conte’ pear. The fruit weight, size and firmness were also improved under the influence of aforementioned treatments. The fruit soluble solids, total sugars, leaf nitrogen, leaf phosphorus and leaf potassium of pear were also enhanced as compared with the control. Additionally, spraying of GA₃ at 150 ppm, as well as, HA at 5 and 4% were the superior treatments and showed the most significant impact on plant growth, yield, fruit quality and leaf mineral content of pear. This study provides a basis for the future elucidation of HA-, GA₃- and CA-modulated molecular mechanisms in pear, which can make a significant contribution in the scientific community. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 997 KiB

Open AccessFeature PaperArticle

Effects of the Preceding Crop on Soil N Availability, Biological Nitrogen Fixation, and Fresh Pod Yield of Organically Grown Faba Bean (Vicia faba L.)

by Dionisios Yfantopoulos, Georgia Ntatsi, Nazim Gruda, Dimitrios Bilalis and Dimitrios Savvas

Horticulturae 2022, 8(6), 496; https://doi.org/10.3390/horticulturae8060496 - 03 Jun 2022

Cited by 5 | Viewed by 1862

Abstract

In the current study, the impact of the preceding crops on growth, fresh pod yield, nitrogen fixation efficiency, and nitrogen nutrition of faba bean (Vicia faba L.) was investigated for two years in both organic and conventional crops. As preceding crops served [...] Read more.

In the current study, the impact of the preceding crops on growth, fresh pod yield, nitrogen fixation efficiency, and nitrogen nutrition of faba bean (Vicia faba L.) was investigated for two years in both organic and conventional crops. As preceding crops served cabbage, pea, and faba bean. The pod number per plant (PN) and the total fresh pod yield (TFPY) were significantly lower with cabbage compared to pea and faba bean as preceding crops in both cropping systems and both experimental years. However, in the organic farming system, pea increased significantly in PN and TFPY compared to faba bean as a preceding crop, while in the conventional system, there was no significant difference between the two legumes. The greater yield performance with the two legumes as preceding crops was associated with higher soil NO₃-N and total-N concentrations at the beginning of the subsequent faba bean crop. The higher soil N availability when the preceding crop was a legume resulted partly from the higher biomass of crop residues left by these crops on the field after harvest, compared to cabbage. However, it was also associated with a more extensive nodulation of the faba bean roots by rhizobia and a higher percentage of N derived from atmosphere (%Ndfa) in their plant tissues, as determined through the natural abundance of the 15N isotope, when the preceding crop was a legume. The cropping system had no impact on pod yield, but organic farming increased the %Ndfa in both years. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 536 KiB

Open AccessArticle

Carbonated Irrigation Assessment of Grapevine Growth, Nutrient Absorption, and Sugar Accumulation in a Tempranillo (Vitis vinifera L.) Vineyard

by Miriam Lampreave, Assumpta Mateos, Josep Valls, Montserrat Nadal and Antoni Sánchez-Ortiz

Agriculture 2022, 12(6), 792; https://doi.org/10.3390/agriculture12060792 - 30 May 2022

Cited by 4 | Viewed by 2746

Abstract

Iron chlorosis is common in vineyards grown on calcareous soils, and consists of a chlorophyll deficiency caused by a disorder in iron nutrition. It is manifested by interveinal yellowing of the youngest leaves and decreased growth and production. Most of the vineyards in [...] Read more.

Iron chlorosis is common in vineyards grown on calcareous soils, and consists of a chlorophyll deficiency caused by a disorder in iron nutrition. It is manifested by interveinal yellowing of the youngest leaves and decreased growth and production. Most of the vineyards in Spain are planted on calcareous soils, so iron chlorosis is frequent, even in tolerant rootstocks. In the case of Spain, Tempranillo accounts for 20.8% of the total Spanish wine area, with this red variety being the most planted. The study of iron chlorosis and the availability of nutrients is essential for improving the qualitative balance of the wine, as it is one of the most representative in our country. The aim of this work was to evaluate how carbonated irrigation modifies soil pH and increases the absorption of nutrients, as well as to assess the impact of chlorosis on the physiology of the variety and the composition of the grape. In the first instance, a test was carried out on bare soil of calcareous composition, evaluating three different levels of carbonated water, and seeing what response it gave to the pH level. The result showed that the dose of 400 ppm of CO₂ provided the optimal pH. Subsequently, in a potted soil, the dose of 400 ppm of CO₂ was evaluated on the variety cv. Tempranillo, in three different compositions of calcareous soil. Results showed that carbonated irrigation increased the levels of chlorophyll impacting on primary metabolism (acids and sugar), plant growth, and higher crop yield, improving the optimal grape ripeness. Given that irrigation with 400 ppm CO₂ increased the ability to control ferric chlorosis, this strategy could be an easy-to-use alternative to iron-based chelates for preventing Fe deficiency in the grapevine as well as moderating the different levels of iron chlorosis. This strategy could be an alternative to the use of synthetic Fe chelates as EDTA or o,o-EDDHA for preventing Fe chlorosis in susceptible Tempranillo (Vitis vinifera L.) vineyard in calcareous soils, with less of a risk to the environment. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 268 KiB

Open AccessArticle

Effects of Rice Straw Combined with Inorganic Fertilizer on Grain Filling and Yield of Common Buckwheat

by Rongyu Guo, Xinyue Zhang, Zhuolei Tang, Yu Zhang and Kaifeng Huang

Agronomy 2022, 12(6), 1287; https://doi.org/10.3390/agronomy12061287 - 27 May 2022

Cited by 5 | Viewed by 2536

Abstract

This study aims to clarify the effect of rice straw combined with inorganic fertilizer on the grain-filling characteristics and yield formation of common buckwheat (Fagopyrum esculentum Moench) and provide a scientific basis for straw fertilizer utilization and the scientific fertilization of common [...] Read more.

This study aims to clarify the effect of rice straw combined with inorganic fertilizer on the grain-filling characteristics and yield formation of common buckwheat (Fagopyrum esculentum Moench) and provide a scientific basis for straw fertilizer utilization and the scientific fertilization of common buckwheat in Guizhou Province.Common buckwheat ‘Fengtian1’ was field-grown and treated with no straw and no fertilization (CK), no straw with normal fertilizer (SF), full straw with 20% reduction in conventional fertilization (SH), full straw with 40% reduction in conventional fertilization (SM), full straw with 80% reduction inconventional fertilization (SL), and full straw with no fertilization (HT). The results showed that the initial growth power (R₀), maximum and average grain-filling rate, and starch synthase activity of the superior grains were higher than those of the inferior grains. Compared with CK, the treatments with straw and inorganic fertilizers remarkably increased the contents of available nitrogen, available potassium, available phosphorus, and organic matter in the rhizosphere of common buckwheat. SH and SF treatments remarkablyimproved the fertilizer contribution rate and fertilizer agronomic utilization rate, promoted root growth, and enhanced the starch branching enzyme and soluble starch synthase activities of superior and inferior grains. Compared with CK, SH treatment considerably increased the number of grains per plant, grain weight per plant, 100-grain weight, and final yield. Thus, straw combined with inorganic fertilizers, particularlythe SH treatment, should be recommended as an agronomic method for promoting grain filling and increasing the yield of common buckwheat. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

15 pages, 1627 KiB

Open AccessArticle

Organic Amendment Types Influence Soil Properties, the Soil Bacterial Microbiome, and Tomato Growth

by Jia-Yang Su, Cheng-Huan Liu, Kimberly Tampus, Ya-Chi Lin and Cheng-Hua Huang

Agronomy 2022, 12(5), 1236; https://doi.org/10.3390/agronomy12051236 - 22 May 2022

Cited by 9 | Viewed by 3348

Abstract

The overuse of chemical fertilizers deteriorates soil quality, and the application of organic amendments has been proposed as an alternative to mineral fertilizers. This study aimed to investigate the effects of organic amendment types on soil properties, the soil microbiome, and tomato growth. [...] Read more.

The overuse of chemical fertilizers deteriorates soil quality, and the application of organic amendments has been proposed as an alternative to mineral fertilizers. This study aimed to investigate the effects of organic amendment types on soil properties, the soil microbiome, and tomato growth. Tomato seedlings were grown in soils applied with ten fertilizer treatments, including a no fertilization control, a chemical fertilization control, and eight organic amendment treatments. Compared with the chemical fertilization treatment, the application of manure compost significantly increased the shoot dry weight of tomato plants. In addition, manure compost and tea seed meal remarkably increased soil organic matter (SOM) in comparison with the no fertilization and chemical fertilization treatments. Moreover, manure compost significantly increased soil-exchangeable K and Mg. The application of neem cake and manure compost significantly increased both bacterial diversity and richness. The relative abundance of Lysinibacillus was significantly positively related to the shoot and total dry weights of tomato plants, and its relative abundance was positively influenced by SOM and soil-exchangeable K. Overall, the manure compost used in this study can increase SOM, soil-exchangeable K and Mg, and the relative abundance of Lysinibacillus, consequently promoting tomato growth. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 3367 KiB

Open AccessArticle

Novel Methodology for the Assessment of Organic Carbon Stocks in German Arable Soils

by Uwe Franko and Joerg Ruehlmann

Agronomy 2022, 12(5), 1231; https://doi.org/10.3390/agronomy12051231 - 21 May 2022

Cited by 1 | Viewed by 1927

Abstract

There is currently a significant focus on oil organic carbon, as interest in mitigating climate change by increasing soil carbon stocks is leading to efforts to include this within carbon farming and the trade of CO₂ certificates. In addition, soil organic carbon [...] Read more.

There is currently a significant focus on oil organic carbon, as interest in mitigating climate change by increasing soil carbon stocks is leading to efforts to include this within carbon farming and the trade of CO₂ certificates. In addition, soil organic carbon controls many other soil functions, such as soil productivity. However, results from long-term field experiments suggest that an ever-increasing carbon content in soil, at some point, will no longer increase productivity, but will cause environmental risks, especially from excess nitrogen. In Germany, the most widely recognized soil organic matter (SOM) balance method, VDLUFA (Association of German Agricultural Investigation and Research Institutions), addresses soil management only, without a relation to the soil carbon stock. To close this gap, a methodology is developed based on results from European long-term field experiments that allows for an assessment of agricultural management both in terms of the carbon input to soil and the amount of carbon stored in soil. Due to the transformation of carbon stock into carbon flux, it is possible to apply the classification scheme of the VDLUFA balance to the carbon content of topsoils. This provides information to qualify further decisions about fostering carbon accumulation. This was demonstrated on experimental results from Bad Lauchstädt, as well as on data from the German Agricultural Soil Inventory (BZE-LW) for arable soils on a regional scale. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 2943 KiB

Open AccessArticle

Status of Essential Elements in Soil and Grain of Organically Produced Maize, Spelt, and Soybean

by Vesna Dragicevic, Milovan Stoiljkovic, Milan Brankov, Miodrag Tolimir, Marijenka Tabaković, Margarita S. Dodevska and Milena Simić

Agriculture 2022, 12(5), 702; https://doi.org/10.3390/agriculture12050702 - 16 May 2022

Cited by 1 | Viewed by 1907

Abstract

Organic agriculture offers many benefits through the increased nutritional quality of produced crops, agro-ecosystem preservation, and climate change mitigation. The development of an efficient nutrient management strategy in low-input systems, such as organic agriculture, which supports soil fertility and essential nutrients absorption by [...] Read more.

Organic agriculture offers many benefits through the increased nutritional quality of produced crops, agro-ecosystem preservation, and climate change mitigation. The development of an efficient nutrient management strategy in low-input systems, such as organic agriculture, which supports soil fertility and essential nutrients absorption by crops, is continually exploring. Thus, a study with maize–spelt–soybean rotation during a 5-year period in organic production was established to evaluate the variability in soil organic matter (SOM) and the status of available elements: N, P, K, Ca, Mg, Fe, Cu, Mn, Zn, and Si from the soil, as well as grain yield (GY) and the content of protein, P, K, Ca, Mg, Fe, Cu, Mn, Zn, and Si concentration in the grain of spelt, maize, and soybean. Significant variations in mineral elements in the soil, GY, and grain composition were detected. Spelt achieved the highest average GY, while soybean grain was the richest in a majority of examined nutrients. The soil Ca content was important for GY, while the protein level in grain was generally tied to the Mn level in the soil. It was recognized that soil–crop crosstalk is an important strategy for macro- and micro-nutrients management in the soil and grain of organically produced spelt, maize, and soybean. While a reduction in the GY and protein concentration in grain was present over time, it was established that a low-input system under dry-farming conditions supports nutrient availability and accumulation in grain, under semi-arid agro-ecological conditions of central Serbia. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1258 KiB

Open AccessArticle

Synergism of Industrial and Agricultural Waste as a Suitable Carrier Material for Developing Potential Biofertilizer for Sustainable Agricultural Production of Eggplant

by Tripti, Adarsh Kumar, Vipin Kumar, Anshumali, L. Benedict Bruno and Mani Rajkumar

Horticulturae 2022, 8(5), 444; https://doi.org/10.3390/horticulturae8050444 - 16 May 2022

Cited by 6 | Viewed by 2633

Abstract

The study investigates biochar from agriculture waste and flyash from coal power station as possible carrier materials for two plant growth-promoting (PGP) bacterial strains Burkholderia sp. L2 and Bacillus sp. A30 for enhanced eggplant growth and yield. Biochar-based biofertilizers with/without flyash showed higher [...] Read more.

The study investigates biochar from agriculture waste and flyash from coal power station as possible carrier materials for two plant growth-promoting (PGP) bacterial strains Burkholderia sp. L2 and Bacillus sp. A30 for enhanced eggplant growth and yield. Biochar-based biofertilizers with/without flyash showed higher viability up to 270 days of storage period. The maximum percentage of seed germination was observed in L2-based biochar and flyash + biochar (1:1) bifertilizer. Moreover, the L2 + biochar+flyash produced a maximum percentage increase in fruit yield with significant (p < 0.05) improvement in plant growth parameters. Post-harvest soil status also showed enhanced physical (water holding capacity, moisture content), chemical (pH, electrical conductivity, NPK), and dehydrogenase activity. The study suggests that biofertilizer of L2 strain with agriculture waste generated biochar and flyash as carrier materials can tremendously enhance the productivity of eggplant and could act as a substitute for chemical fertilizer thus solving their disposal problem by sustainable waste management. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 1940 KiB

Open AccessArticle

Response of Growth, Yield, and Phytochemical Behavior of Jojoba Genotypes to Azolla filiculoides Plant Extract

by Amira K. G. Atteya, Aishah N. Albalawi, Hala M. Bayomy, Eman S. Alamri and Esmail A. E. Genaidy

Plants 2022, 11(10), 1314; https://doi.org/10.3390/plants11101314 - 16 May 2022

Cited by 1 | Viewed by 1910

Abstract

A unique storage lipid wax found in jojoba seeds can be employed as a chemical feedstock. Alternative safe and natural sources of plant nutrients are constantly sought to preserve both human health and the environment. As a result, EAI1, EAI2, and EAI3 jojoba [...] Read more.

A unique storage lipid wax found in jojoba seeds can be employed as a chemical feedstock. Alternative safe and natural sources of plant nutrients are constantly sought to preserve both human health and the environment. As a result, EAI1, EAI2, and EAI3 jojoba genotypes’ growth, yield, and phytochemical behavior in response to Azolla extract at concentrations of 0, 10, and 30% were studied. Maximum productivity was found with EAI1, followed by EAI3 then EAI2 across all Azolla extracts. In relation to the Azolla extract concentrations in the two seasons, the concentration of 30% delivered the most pronounced results across all the studied genotypes. During the two seasons, administration of a combined treatment of the EAI1 jojoba genotype with 30% Azolla extract produced the highest mean values of growth, flowering, and fruiting, as well as chemical composition parameters. This means that the treatment of EAI1 genotype with 30% Azolla filiculoides Lam. plant extract yielded the highest significant seed yield (3748 and 3839 kg ha⁻¹) and oil yield per hectare (1910 and 2002 L ha⁻¹). The combination treatment of the EAI1 jojoba genotype with 10% Azolla extract yielded the highest proportion of gadoleic fatty acid (49.83%). Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2366 KiB

Open AccessArticle

Neutralization of Industrial Alkali-Contaminated Soil by Different Agents: Effects and Environmental Impact

by Jiaqi Shi, Tao Long, Liping Zheng, Shang Gao and Lei Wang

Sustainability 2022, 14(10), 5850; https://doi.org/10.3390/su14105850 - 11 May 2022

Cited by 3 | Viewed by 2574

Abstract

Industrial soil is susceptible to acid or alkali pollution, but studies focused on the remediation of such soil are still limited. This manuscript investigated the neutralization effect of five agents (hydrochloric acid, citric acid, ferrous sulfate, calcium superphosphate and raw gypsum) to alkali [...] Read more.

Industrial soil is susceptible to acid or alkali pollution, but studies focused on the remediation of such soil are still limited. This manuscript investigated the neutralization effect of five agents (hydrochloric acid, citric acid, ferrous sulfate, calcium superphosphate and raw gypsum) to alkali polluted soil. The results showed that regarding the initial pH after the neutralizing agent addition, it was better to set it lower than the target, as the pH would rebound. None of the five agents caused an obvious increase in the heavy metal contents of the leachates, but they all caused an increase in electrical conductivity, which indicated an increase in soil salinity. The leachates showed a luminous gain to Vibrio fischeri. However, remediation with hydrochloric acid would cause significant inhibition of germination and root elongation of pakchoi. In addition, the addition of neutralizing agents reshaped the soil microbial community structure in different patterns. Soils treated with hydrochloric acid and ferrous sulfate seemed to improve the microbial richness. The neutralization might be favorable for the biodegradation of polycyclic aromatic hydrocarbons (PAHs), which usually coexist in industrial contaminated soil. In general, the neutralization of alkaline industrial soils using ferrous sulfate, superphosphate and gypsum brought minimal environmental risk, among which ferrous sulfate was the first recommendation in industrial soil after a comprehensive comparison. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 3305 KiB

Open AccessArticle

Towards Balanced Fertilizer Management in South China: Enhancing Wax Gourd (Benincasa hispida) Yield and Produce Quality

by Xiao Chen, Xiaodong Chen, Jiabin Jiao, Fusuo Zhang, Xinping Chen, Guohua Li, Zhao Song, Eldad Sokolowski, Patricia Imas, Hillel Magen, Amnon Bustan, Yuzhi He, Dasen Xie and Baige Zhang

Sustainability 2022, 14(9), 5646; https://doi.org/10.3390/su14095646 - 07 May 2022

Cited by 3 | Viewed by 2227

Abstract

Balanced fertilizer management promotes plant growth, enhances produce quality, minimizes inputs, and reduces negative environmental impacts. Wax gourd (Benincasa hispida) is an important vegetable crop species in China and in South Asia. Two crop nutrition options, NPK and the natural mineral [...] Read more.

Balanced fertilizer management promotes plant growth, enhances produce quality, minimizes inputs, and reduces negative environmental impacts. Wax gourd (Benincasa hispida) is an important vegetable crop species in China and in South Asia. Two crop nutrition options, NPK and the natural mineral polyhalite, were tested, separately and combined, with the aim of enhancing wax gourd yield and quality and simultaneously to increase nutrient use efficiency and reducing inputs. The experiments tested the optimization of NPK by reducing the proportion of phosphorus (P), and the effect of enriching the soil with essential macronutrients by the use of the supplementary mineral fertilizer polyhalite containing magnesium (Mg), calcium (Ca) and sulfur (S). Two experiments were carried out in Foshan County, Guangdong, China, in 2018 and 2019. Experiments included four treatments: (1) Conventional NPK (15:15:15); (2) Optimized NPK (16:8:18); (3) Conventional NPK + polyhalite; (4) Optimized NPK + polyhalite. Fertilizers were applied prior to planting. While optimized NPK alone had no effects on fruit yield and quality, supplementary polyhalite resulted in a 10–17% increase in yield and significantly improved produce quality due to increased nutrient uptake from polyhalite, resulting in better foliar biomass. We conclude that the combined crop nutrition options improved yield and quality, enhanced nutrient use efficiency, and reduced risks of nutrient pollution. Inclusion of polyhalite in balanced fertilization practices as a supplementary source of secondary macronutrients seems promising. Nevertheless, plenty of space remains open for further adjustments of NPK application management, focusing on reduced rates, optimized ratio, and accurate timing of application for each nutrient. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1650 KiB

Open AccessArticle

Supplementation of Manure Compost with Trichoderma asperellum Improves the Nutrient Uptake and Yield of Edible Amaranth under Field Conditions

by Ruei-Teng Lyu and Cheng-Hua Huang

Sustainability 2022, 14(9), 5389; https://doi.org/10.3390/su14095389 - 29 Apr 2022

Cited by 2 | Viewed by 1381

Abstract

Manure composts can improve soil health and crop production, but their application with Trichoderma species has not been well evaluated in amaranth cultivation. This study aimed to determine the effects of manure compost (MC) and MC supplemented with Trichoderma asperellum CHF 78 [...] Read more.

Manure composts can improve soil health and crop production, but their application with Trichoderma species has not been well evaluated in amaranth cultivation. This study aimed to determine the effects of manure compost (MC) and MC supplemented with Trichoderma asperellum CHF 78 (MC+CHF 78) on the yield and nutrient uptake of amaranth, as well as on soil properties, under field conditions. Four fertilization treatments, including a control without fertilization, chemical fertilization (CF), MC, and MC+CHF 78, were arranged in a randomized complete block design with six replications in the experimental field. MC and MC+CHF 78 significantly increased the yield of amaranth by 96.2–102% in comparison with CF. In addition, MC and MC+CHF 78 significantly increased the soil pH, soil organic matter, soil available P and exchangeable K, and soil microbial activity compared with those in the control and CF treatments. However, only amaranth plants applied with MC+CHF 78 showed a significantly greater P uptake than those with the control and CF treatments, which may be attributed to the phosphate-solubilizing ability of T. asperellum CHF 78. In conclusion, manure compost fortified with T. asperellum CHF 78 can be used as an alternative to chemical fertilizers for amaranth cultivation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 8946 KiB

Open AccessArticle

Coupled Bionic Design of Liquid Fertilizer Deep Application Type Opener Based on Sturgeon Streamline to Enhance Opening Performance in Cold Soils of Northeast China

by Jinwu Wang, Nuan Wen, Ziming Liu, Wenqi Zhou, Han Tang, Qi Wang and Jinfeng Wang

Agriculture 2022, 12(5), 615; https://doi.org/10.3390/agriculture12050615 - 26 Apr 2022

Cited by 8 | Viewed by 2113

Abstract

Liquid fertilizer has many advantages, such as low production cost and little environmental pollution. Liquid fertilizer open furrow strip application method is widely used in fertilizer application operation. The widely used core-share furrow opener has a high operational resistance, disturbing the soil, hurting [...] Read more.

Liquid fertilizer has many advantages, such as low production cost and little environmental pollution. Liquid fertilizer open furrow strip application method is widely used in fertilizer application operation. The widely used core-share furrow opener has a high operational resistance, disturbing the soil, hurting the crop roots, causing the liquid fertilizer to volatilize and deteriorating the fertilization effect. In this study, based on the streamline curve of the sturgeon body, we designed several bionic sturgeon liquid fertilizer deep application openers by combining bionics and analyzed the effects of several openers under different operating speeds on open furrow resistances and soil disturbance based on the discrete element method. The mechanism of open furrow resistances reduction and efficient soil backfill of the bionic structure were verified by indoor soil bin tests. The test results show that, compared with the core-share type furrow opener, both open furrow resistances and soil disturbance of the bionic sturgeon liquid fertilizer deep application opener are smaller. This study provides theoretical and practical references for the design of liquid fertilizer deep application openers. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1436 KiB

Open AccessArticle

Effects of Biochar-Based Fertilizers on Energy Characteristics and Growth of Black Locust Seedlings

by Ting Gao, Qian Zhu, Zhidong Zhou, Yongbo Wu and Jianhui Xue

Sustainability 2022, 14(9), 5045; https://doi.org/10.3390/su14095045 - 22 Apr 2022

Cited by 2 | Viewed by 1601

Abstract

To understand ecological and energy problems in the karst area of Guizhou, China, the effects of using biochar-based fertilizers on the energy characteristics of different species of black locust were studied. To determine the most suitable species and the best rational application method [...] Read more.

To understand ecological and energy problems in the karst area of Guizhou, China, the effects of using biochar-based fertilizers on the energy characteristics of different species of black locust were studied. To determine the most suitable species and the best rational application method of biochar, an outdoor pot experiment was performed using three species of black locust (White-flowered locust (W), Hong-sen locust (S), and Large-leaf fast-growing locust (L)). There were six treatments: control (CK), MF, RH2MF, RH4MF, W2MF, and W4MF (M—compost; F—NPK fertilizer; RH—rice husk biochar; and W—wood biochar), where the numbers represented the mass ratio of biochar to soil. Biochar-based fertilizers had significant effects on the total organic carbon (TOC), total nitrogen (TN), total potassium (TK), branch gross calorific values (GCV), and ash removal calorific values (AFCV) of seedlings. RH4MF had the best overall values. Different species had significant effects in all indicators (except for TN); the effect on S was better than that of W and L. Principal component analysis showed that RH4MF-S had the highest comprehensive scores. In summary, Hong-sen locust (S) was a high-quality energy species and RH4MF may be used as fertilization for energy forest development. This study provides a reference for future long-term energy forest research in this area. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 17184 KiB

Open AccessArticle

No-Tillage Combined with Appropriate Amount of Straw Returning Increased Soil Biochemical Properties

by Wanhua Chen, Wei Yuan, Jie Wang, Ziyang Wang, Zhengping Zhou and Shiping Liu

Sustainability 2022, 14(9), 4875; https://doi.org/10.3390/su14094875 - 19 Apr 2022

Cited by 6 | Viewed by 1912

Abstract

(1) Background: Few studies have focused on the interaction of tillage and straw returning on soil carbon and nitrogen. Therefore, this study was conducted for investigating the effects of tillage and straw returning on soil biochemical properties under a rice–wheat double cropping system; [...] Read more.

(1) Background: Few studies have focused on the interaction of tillage and straw returning on soil carbon and nitrogen. Therefore, this study was conducted for investigating the effects of tillage and straw returning on soil biochemical properties under a rice–wheat double cropping system; (2) Methods: Six treatments were set up to determine soil biochemical properties, including no-tillage with all straw returning (NTS), wheat plow tillage and rice no-tillage with half straw returning (RT1), wheat no-tillage and rice plow tillage with half straw returning (RT2), plow tillage with all straw returning (CTS), less tillage with half straw returning (MTS), and plow tillage with no straw returning (CT); (3) Results: Straw returning increased soil microbial biomass carbon (SMBC) and soil microbial biomass nitrogen (SMBN), but had no significant effects on total nitrogen (TN) and soil organic carbon (SOC). In the treatments of straw returning, the contents of SMBC, SMBN, TN, and SOC under no-tillage were increased in the 0–7 cm soil layer. Tillage and straw returning had no significant effects in the 7–14 cm and 14–21 cm soil layers. In addition, SMBC/SMBN for all the treatments was maintained within a reasonable range, and microbial quotient (SMQ) and SMBN/TN in the no-tillage treatment had a significant improvement; (4) Conclusions: The results showed that no-tillage with an appropriate amount of straw returning improved the soil biochemical properties and maintained the nitrogen mineralization capacity in the 0–7 cm soil layer for this region. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 5877 KiB

Open AccessArticle

Soil Responses to High Olive Mill Wastewater Spreading

by Leïla Chaâri, Norah Salem Alsaiari, Abdelfattah Amari, Faouzi Ben Rebah, Monem Kallel and Tahar Mechichi

Agronomy 2022, 12(4), 972; https://doi.org/10.3390/agronomy12040972 - 18 Apr 2022

Cited by 6 | Viewed by 2375

Abstract

Olive manufacturing generates the most polluting wastewater. Olive mill wastewater (OMW) contains a large amount of organic and inorganic fractions. Olive-oil-producing countries have investigated several treatments and valorization processes for better management of this waste. The Tunisian government adopted OMW spreading on soil [...] Read more.

Olive manufacturing generates the most polluting wastewater. Olive mill wastewater (OMW) contains a large amount of organic and inorganic fractions. Olive-oil-producing countries have investigated several treatments and valorization processes for better management of this waste. The Tunisian government adopted OMW spreading on soil to manage the waste and improve the organic matter in the soil of olive groves. The examination of soil after OMW spreading was set up to assess the physicochemical changes and better comprehend the soil’s responses. An incubation of two types of artificial soil treated with 40 and 80 m³·ha⁻¹ of OMW led to increased organic matter, phosphorus, nitrogen and potassium contents. The adsorption of the phenolic compounds in soil was dependent on the clay type and was shown by the behavior of the soil composed of bentonite clay. The germination index of tomato and alfalfa seeds recorded a positive test with OMW applied on soil, and it was in relation to the species utilized. This practice seems to be a solution for the management of OMW because it limits the use of chemical fertilizers and might be a convenient source of carbon in organic farming. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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25 pages, 6479 KiB

Open AccessArticle

Effect of Ammonium Sulphate Incorporated with Calcium Nitrate Fertilizers on Nutritional Status, Fruit Set and Yield of Pomegranate Trees cv. Wonderful

by Naji Mordi Naji Al-Dosary, Mahmoud Abdel-Sattar and Abdulwahed M. Aboukarima

Agronomy 2022, 12(4), 971; https://doi.org/10.3390/agronomy12040971 - 17 Apr 2022

Cited by 5 | Viewed by 4337

Abstract

The effect of (NH₄)₂SO₄:Ca(NO₃)₂ ratios applied by fertigation on nutritional status, fruit set, yield, and marketable yield of pomegranate trees cv. Wonderful was evaluated. The trees were provided with five nutrient solutions with the [...] Read more.

The effect of (NH₄)₂SO₄:Ca(NO₃)₂ ratios applied by fertigation on nutritional status, fruit set, yield, and marketable yield of pomegranate trees cv. Wonderful was evaluated. The trees were provided with five nutrient solutions with the same total nitrogen level (200 units/ha) but with different (NH₄)₂SO₄:Ca(NO₃)₂ ratios (100:0, 90:10, 80:20, 70:30, and 60:40). Increasing the (NH₄)₂SO₄ ratio from 60 to 100% significantly reduced the nitrogen (N), magnesium (Mg), calcium (Ca), and potassium (K) concentrations while significantly increasing P and Fe concentrations in pomegranate leaves. The highest (NH₄)₂SO₄ proportion (100%) induced a reduction in both chlorophyll content and dry matter values in pomegranate leaves. The maximum fruit set (33.65% and 31.40%) and the minimum fruit drop (6.74% and 6.25%) were recorded at the applied ratio of 60% of (NH₄)₂SO₄:40% of Ca(NO₃)₂. The applied proportion of 70% of (NH₄)₂SO₄:30% of Ca(NO₃)₂ provided the minimum fruit sunburn (9.54% and 9.74%) and fruit cracking (6.45% and 5.64%), maximum yield (33.62 and 33.00 kg/tree), and marketable yield (27.41 and 27.93 kg/tree) in the 2019 and 2020 seasons, respectively. Our results provide valuable information about the effects of partial replacement of nitrogen fertilizer from (NH₄)₂SO₄ with nitrogen fertilizer from Ca(NO₃)₂ on the growth characteristics of pomegranate trees cv. Wonderful. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 1362 KiB

Open AccessArticle

An Integrated Nitrogen Management Strategy Promotes Open-Field Pepper Yield, Crop Nitrogen Uptake, and Nitrogen Use Efficiency in Southwest China

by Xiao Ma, Fen Zhang, Fabo Liu, Guangzheng Guo, Taihong Cheng, Junjie Wang, Yuanpeng Shen, Tao Liang, Xinping Chen and Xiaozhong Wang

Agriculture 2022, 12(4), 524; https://doi.org/10.3390/agriculture12040524 - 07 Apr 2022

Cited by 7 | Viewed by 2339

Abstract

Excessive nitrogen (N) fertilizer application is a serious issue in intensive vegetable production and can negatively affect vegetable productivity and N use efficiency (NUE). The optimization of the N fertilizer rate and application of enhanced efficiency N fertilizers (EENFs), including nitrification inhibitors (Nis) [...] Read more.

Excessive nitrogen (N) fertilizer application is a serious issue in intensive vegetable production and can negatively affect vegetable productivity and N use efficiency (NUE). The optimization of the N fertilizer rate and application of enhanced efficiency N fertilizers (EENFs), including nitrification inhibitors (Nis) and controlled-release fertilizer (CRF), are widely recognized as feasible N management strategies to resolve the problem of unreasonable N fertilizer input. Therefore, we conducted a 2-year field experiment (2019–2020) in an open-field vegetable system (pepper, Capsicum annuum L.) in southwest China to investigate the effects of an optimized N application rate and EENFs on vegetable yield, NUE, and crop N uptake. The following N management treatments were established: control without N fertilizer input (CK); optimized N fertilizer rate as urea (OPT); farmers’ fertilizer practice (FP); application of a nitrification inhibitor (NI) within the optimized N fertilizer rate; and application of controlled-release fertilizer (CRF) within the optimized N fertilizer rate. The results showed that the OPT treatment based on root zone N management achieved a 37.5% reduction in the N application rate without compromising vegetable yield and increased the recovery efficiency of N (REN) by 31.5% compared to the FP treatment. Furthermore, the combined application of the NI or CRF treatments with the OPT treatment resulted in greater vegetable yields, fruit N uptake, and REN (9.54%, 26.8%, and 27.6%, respectively, for NI; 10.5%, 28.7%, and 28.8%, respectively, for CRF) than the OPT treatment alone. The absorption ratio of fruit N uptake to total crop N uptake was also increased. Our results clearly showed that the combined application of EENFs with the OPT treatment could achieve the win–win benefits of a yield increase and improved REN in Chinese vegetable production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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25 pages, 1311 KiB

Open AccessReview

Non-Essential Elements and Their Role in Sustainable Agriculture

by Marta Nunes da Silva, Joana Machado, Jazmin Osorio, Rafael Duarte and Carla S. Santos

Agronomy 2022, 12(4), 888; https://doi.org/10.3390/agronomy12040888 - 06 Apr 2022

Cited by 12 | Viewed by 5830

Abstract

Agricultural systems are constantly under environmental pressure, and the continuous rise of the global population requires an increasingly intensification of agronomical productivity. To meet the current global food demand, particularly in depleted ecosystems under adverse climate conditions, the development of novel agronomical practices, [...] Read more.

Agricultural systems are constantly under environmental pressure, and the continuous rise of the global population requires an increasingly intensification of agronomical productivity. To meet the current global food demand, particularly in depleted ecosystems under adverse climate conditions, the development of novel agronomical practices, which ensure crop productivity while safeguarding minimal impact to the environment, must be encouraged. Since aluminium (Al), cobalt (Co), selenium (Se), silicon (Si) and sodium (Na) are not essential to plant metabolism, their benefits are often neglected or underestimated in agriculture; however, several studies support their advantages in sustainable agriculture when properly employed. The agronomical uses of these elements have been studied in the last decades, delivering important cues for the improvement of food and feed production worldwide due to beneficial effects in plant growth and productivity, nutrient balance, pest and pathogen resistance, water stress management, heavy-metal toxicity alleviation, and postharvest performance. However, their application has not been addressed as part of a holistic conservation strategy that supports the sustainability of agroecosystems. Here, we discuss the potential use of these elements in sustainable agriculture, and the knowledge gaps that hinder their effective integration into agronomical practices, which result in equally profitable applications while supporting environmental sustainability. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 1960 KiB

Open AccessArticle

Excessive Nitrogen Fertilization Is a Limitation to Herbage Yield and Nitrogen Use Efficiency of Dairy Pastures in South Africa

by Motsedisi P. Phohlo, Pieter A. Swanepoel and Stefan Hinck

Sustainability 2022, 14(7), 4322; https://doi.org/10.3390/su14074322 - 06 Apr 2022

Cited by 2 | Viewed by 1907

Abstract

The response of crop yields to fertilizers is a long-standing topic of agricultural production. Currently, in dairy-pasture systems, nitrogen (N) fertilizer is used as a management tool that is said to be directly proportional to pasture yield. We evaluated a large dataset consisting [...] Read more.

The response of crop yields to fertilizers is a long-standing topic of agricultural production. Currently, in dairy-pasture systems, nitrogen (N) fertilizer is used as a management tool that is said to be directly proportional to pasture yield. We evaluated a large dataset consisting of data from 153 fields over five years to examine the effects of N fertilization on pasture yield and nitrogen use efficiency in the Eastern Cape province of South Africa. Fertilizer application rates were grouped into three treatments viz., <200, 200–350, and >350 kg N ha⁻¹, and herbage yield response over the years was analyzed with mixed models. There were no differences found between treatments for total annual herbage yield over the years. High N fertilizer rates did not translate to a higher herbage yield of pastures. The N rate had a weak but significant negative correlation with the total annual yield and only accounted for 6% of the yield variation. The N use efficiency of pastures improved with reduced N application rates. Pasture yield varies through different seasons. Spring and summer account for the highest yield, coinciding with warm and moist conditions favorable for N mineralization in the soil. Farmers need to consider the time of the year and plan their monthly or seasonal fertilizer application accordingly to account for peak N mineralization rates. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 4276 KiB

Open AccessArticle

Soil Nutrient Contents in East African Climate-Smart Villages: Effects of Climate-Smart Agriculture Interventions

by John Walker Recha, Gebermedihin Ambaw, Abebe Nigussie, Maren Radeny and Dawit Solomon

Agriculture 2022, 12(4), 499; https://doi.org/10.3390/agriculture12040499 - 31 Mar 2022

Cited by 5 | Viewed by 2468

Abstract

Short-term and plot-level trials mostly produce data on the advantages of climate-smart agriculture (CSA) practices on food security in a changing climate. Previous studies evaluated only one or a combination of a few CSA practices that improved soil nutrients, particularly in the landscapes [...] Read more.

Short-term and plot-level trials mostly produce data on the advantages of climate-smart agriculture (CSA) practices on food security in a changing climate. Previous studies evaluated only one or a combination of a few CSA practices that improved soil nutrients, particularly in the landscapes of East Africa; hence, it is difficult to draw general conclusions. In this study, we evaluated the effect of CSA practices portfolio on soil macronutrient (nitrogen, phosphorus, and potassium) and micronutrient (manganese and zinc) levels in climate-smart villages (CSVs) in Uganda, Kenya, and Tanzania over a six-year period across different land uses such as agroforestry, cropland, grassland, forest, and control (without CSA practices). A total of 432 soil samples were collected at depths of 0–15, 15–45, and 45–100 cm, and analyzed for macro- and micronutrients. CSA practices increased total nitrogen (TN), phosphorus (P), and potassium (K) regardless of land use type or soil depth. TN, P, and K were mainly stored in surface soil (0–15 cm), accounting for 50.8–52.5%, 47.0–79.5%, and 34.2–65.5% respectively. Concentrations of Mn and Zn were 1.5–3.6 and 5.1–15.6 times greater under CSA than those under the control, respectively, at all soil depths. Results suggest that CSA practices implemented using the landscape approach contributed to improved soil fertility, which is critical in developing more sustainable and resilient production systems among smallholder farmers. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2063 KiB

Open AccessArticle

No-Tillage with Residue Retention and Foliar Sulphur Nutrition Enhances Productivity, Mineral Biofortification and Crude Protein in Rainfed Pearl Millet under Typic Haplustepts: Elucidating the Responses Imposed on an Eight-Year Long-Term Experiment

by Ankit, Ram Swaroop Bana, Kuldeep Singh Rana, Raj Singh, Samarth Godara, Minakshi Grover, Achchhelal Yadav, Anil Kumar Choudhary, Teekam Singh, Mukesh Choudahary, Ruchi Bansal, Nirupma Singh, Vipin Mishra, Amresh Choudhary and Akshay Kumar Yogi

Plants 2022, 11(7), 943; https://doi.org/10.3390/plants11070943 - 30 Mar 2022

Cited by 11 | Viewed by 2177

Abstract

Yield limitation and widespread sulphur (S) deficiency in pearl-millet-nurturing dryland soils has emerged as a serious threat to crop productivity and quality. Among diverse pathways to tackle moisture and nutrient stress in rainfed ecologies, conservation agriculture (CA) and foliar nutrition have the greatest [...] Read more.

Yield limitation and widespread sulphur (S) deficiency in pearl-millet-nurturing dryland soils has emerged as a serious threat to crop productivity and quality. Among diverse pathways to tackle moisture and nutrient stress in rainfed ecologies, conservation agriculture (CA) and foliar nutrition have the greatest potential due to their economic and environmentally friendly nature. Therefore, to understand ammonium thiosulphate (ATS)-mediated foliar S nutrition effects on yield, protein content, mineral biofortification, and sulphur economy of rainfed pearl millet under diverse crop establishment systems, a field study was undertaken. The results highlighted that pearl millet grain and protein yield was significantly higher under no-tillage +3 t/ha crop residue mulching (NTCRM) as compared to no-tillage without mulch (NoTill) and conventional tillage (ConvTill), whereas the stover yield under NTCRM and ConvTill remained at par. Likewise, grain and stover yield in foliar S application using ATS 10 mL/L_twice was 19.5% and 13.2% greater over no S application. The sulphur management strategy of foliar-applied ATS 10 mL/L_twice resulted in significant improvement in grain protein content, protein yield, micronutrient fortification, and net returns (₹ 54.6 × 1000) over the control. Overall, ATS-mediated foliar S nutrition can be an alternate pathway to S management in pearl millet for yield enhancement, micronutrient biofortification and grain protein content increase under ConvTill, as well as under the new NTCRM systems. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 3630 KiB

Open AccessArticle

Straw-Soil-Rotary Blade Interaction: Interactive Effects of Multiple Operation Parameters on the Straw Movement

by Gaoming Xu, Yixuan Xie, Lei Liang, Qishuo Ding, Huanxiong Xie and Jiannan Wang

Agronomy 2022, 12(4), 847; https://doi.org/10.3390/agronomy12040847 - 30 Mar 2022

Cited by 8 | Viewed by 2335

Abstract

Conventional soil-tool interaction has been upgraded to straw-soil-tool interaction due to plenty of straw remains in the field after harvesting. Understanding the straw-soil-tool interaction relationship and quantifying the straw movement and distribution characteristics at various tillage operation parameters is critical for straw management [...] Read more.

Conventional soil-tool interaction has been upgraded to straw-soil-tool interaction due to plenty of straw remains in the field after harvesting. Understanding the straw-soil-tool interaction relationship and quantifying the straw movement and distribution characteristics at various tillage operation parameters is critical for straw management and the design of tillage tools. Here, in order to investigate the interactive effects of key operation parameters on the displacement and burial of straw, a specific field test rig was developed to perform straw movement test. According to the singe-factor test and multifactor interactive experiment, we investigated the effect of straw length, tillage depth and rotary speed on straw movement, and established a mathematical model between operation parameters and straw movement. The results showed that the significant order of the influence on the displacement and burial of straw was as follows: the tillage depth, the straw length, the rotary speed. As determined by response surface analysis, the optimal combination of parameters for straw incorporation was straw length of 5 cm, tillage depth of 13 cm, and rotary speed of 320 rpm, and the corresponding straw burial rate and straw displacement were 95.5% and 27.6 cm, respectively. The relative errors of the optimization results are less than 5%. These results indicated that the mathematical model can be used to predict and evaluate straw movement. Therefore, it is feasible to enhance the straw incorporation performance by a reasonable setting of operation parameters, which may provide a comprehensive strategy to improve the working quality of tillage tools. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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21 pages, 17847 KiB

Open AccessArticle

Effect of Long-Term Fertilization on Aggregate Size Distribution and Nutrient Accumulation in Aeolian Sandy Soil

by Ziru Niu, Fangjiao An, Yongzhong Su, Tingna Liu, Rong Yang, Zeyu Du and Shiyang Chen

Plants 2022, 11(7), 909; https://doi.org/10.3390/plants11070909 - 29 Mar 2022

Cited by 4 | Viewed by 2324

Abstract

Soil aggregates are the material basis of soil structure and important carriers of nutrients. Long-term application of organic and inorganic fertilizers can affect the composition of soil aggregates to varying degrees, which in turn affects the distribution and storage of soil nutrients. We [...] Read more.

Soil aggregates are the material basis of soil structure and important carriers of nutrients. Long-term application of organic and inorganic fertilizers can affect the composition of soil aggregates to varying degrees, which in turn affects the distribution and storage of soil nutrients. We report the results of a 15-year long-term field-based test of aeolian sandy soil and used the wet sieve method to analyze the stability of water-stable aggregates, as well as the distribution characteristics of nutrients in different particle size aggregates. Our results show that long-term application of organic fertilizer (M3) and combined organic–inorganic treatments (NPK1-M1, NPK1-M2, and NPK1-M3) help to increase the amount of organic carbon, inorganic carbon, and cation exchange in the macro-aggregates, and the improvement rates are 92–103%, 8–28%, and 74–85%, respectively. The organic content of the fertilizers also promotes the formation of macro-aggregates, and the stability of aggregates increase from 0.24 to 0.45. In contrast, the application of inorganic fertilizers (NPK1, NPK2, and NPK3) has no marked effect on the formation and stability of macro-aggregates; the application of inorganic fertilizers can merely maintain the organic carbon content of the soil. Correlation analysis shows that the application of organic fertilizers and chemical (inorganic) fertilizers containing phosphorus and potassium can markedly increase the content and reserves of available phosphorus and potassium across all aggregate sizes, and there is a significant positive correlation between these parameters and the amount of applied fertilizer (p < 0.05). Aggregates of various sizes in aeolian sandy soils in arid areas have the potential for greater nutrient storage. Therefore, organic fertilizers can be used in the agricultural production process to improve soil structure and fertility. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 1656 KiB

Open AccessReview

Plant Growth-Promoting Halobacteria and Their Ability to Protect Crops from Abiotic Stress: An Eco-Friendly Alternative for Saline Soils

by Jessie Hernández-Canseco, Angélica Bautista-Cruz, Saúl Sánchez-Mendoza, Teodulfo Aquino-Bolaños and Patricia S. Sánchez-Medina

Agronomy 2022, 12(4), 804; https://doi.org/10.3390/agronomy12040804 - 27 Mar 2022

Cited by 17 | Viewed by 5016

Abstract

Arid and semi-arid soils display low productivity due to abiotic stress associated with drought and salinity. Halobacteria can increase the yield of crops grown under these types of stress. These bacteria thrive across a wide salinity range (1–25% NaCl) and also in the [...] Read more.

Arid and semi-arid soils display low productivity due to abiotic stress associated with drought and salinity. Halobacteria can increase the yield of crops grown under these types of stress. These bacteria thrive across a wide salinity range (1–25% NaCl) and also in the absence of NaCl and have direct and indirect mechanisms that promote plant growth. This review summarizes studies conducted over the past five years that have assessed the effect of halobacteria on plants and soil fertility. The criteria used in the selection of halobacteria were also reviewed. Few studies have assessed the impact of halobacteria on soil fertility. The selection of halobacteria has been based on a qualitative criterion considering the morphology of colonies grown in media enriched with salts, mainly Na⁺. Not all bacteria growing in salt-enriched media are capable of capturing Na⁺ ions. Therefore, a quantitative criterion should be applied for the selection of halobacteria, which could be their ability to capture Na⁺ ions in vitro. This, together with the assessment of the effect of halobacteria on soil fertility, may largely contribute to the recovery of saline soils. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 220 KiB

Open AccessProject Report

Comparison of Crop Yield Estimates Obtained from an Historic Expert System to the Physical Characteristics of the Soil Components—A Project Report

by Edward B. Rayburn and Tom Basden

Agronomy 2022, 12(4), 765; https://doi.org/10.3390/agronomy12040765 - 22 Mar 2022

Cited by 2 | Viewed by 1919

Abstract

Crop yields vary due to soil type. Expected crop yields are reported in published soil surveys based on the knowledge of local conservation and extension professionals. Crop yields have increased over the years due to improved genetics and management. The objective of this [...] Read more.

Crop yields vary due to soil type. Expected crop yields are reported in published soil surveys based on the knowledge of local conservation and extension professionals. Crop yields have increased over the years due to improved genetics and management. The objective of this project was to compare historic expected crop yields to soil physical characteristics and to update expected yields for West Virginia soils in the United States National Soils Information System (NASIS). Regression analysis found that soil physical characteristics explained 57 to 65% of the variation in corn and hay yields. Corn and hay yield regressions calculated from a regression data set predicted yields for crops on soils in a test data set without bias and with residual errors of 10 to 15%. Updated crop yields under good management on more productive soils were obtained by surveying farmers and variety trials conducted in West Virginia and surrounding states. The updated yields and relative historic yields were used proportionally to update expected crop yields by soil series. The updated yields were reviewed by local conservation professionals and adjusted as needed based on local experience. These updated yields are now being used as the expected crop yield for the West Virginia soil series in the NASIS. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

15 pages, 2638 KiB

Open AccessArticle

Nutrient Characterization in Soil Aggregate Fractions with Different Fertilizer Treatments in Greenhouse Vegetable Cultivation

by Jun Wang, Wei Dai, Kaikai Fang, Hui Gao, Zhimin Sha and Linkui Cao

Agriculture 2022, 12(4), 440; https://doi.org/10.3390/agriculture12040440 - 22 Mar 2022

Cited by 3 | Viewed by 2105

Abstract

Fertilization affects the formation and stability of soil aggregate, as well as the nutrient status of soil aggregate. However, the potential effect of compost on soil aggregate and its nutrient characteristics is still unclear. In view of this, we conducted a greenhouse vegetable [...] Read more.

Fertilization affects the formation and stability of soil aggregate, as well as the nutrient status of soil aggregate. However, the potential effect of compost on soil aggregate and its nutrient characteristics is still unclear. In view of this, we conducted a greenhouse vegetable cultivation experiment to evaluate soil water-stable aggregate (WSA) and its stability indices and aggregate nutrient stoichiometry characteristics at 0 to 20 cm soil depth with four treatments: (1) no fertilizer (CK), (2) chemical fertilizer (CF), (3) organic fertilizer (OF), and (4) chemical fertilizer plus organic fertilizer (CO). The results showed that the proportion of the 2 to 0.25 mm fraction was the greatest, followed by 0.25 to 0.053 mm, which accounted for 41.83 to 49.53% and 28.60 to 31.88% by weight, respectively. The mean weight diameter (MWD) value and the proportion of the >0.25 mm fraction in the CF, OF, and CO treatments were significantly higher than in the CK treatment. Within the fertilization treatments, the MWD and the proportion of the >0.25 mm fraction in the CO were significantly higher than those in CF and OF. Among all the aggregates, the soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents were the highest in the fraction of 0.25 to 0.053 mm. The CF, OF, and CO treatments significantly increased the SOC, TN, and TP contents compared with the CK treatment. The SOC content of fractions >2 mm and 0.25 to 0.053 mm in the CO treatment was significantly higher than that of the CF and OF treatments, and the TN and TP contents in all the aggregates (except < 0.053 mm) were the highest in the CO treatment. The SOC, TN, and TP contents in the 2 to 0.25 mm and 0.25 to 0.053 mm components contributed greatly to the soil SOC, TN, and TP reserves. There was no noticeable difference in the nutrient stoichiometry of the soil aggregate between the different treatments. Redundancy analysis (RDA) revealed that the soil physicochemical factors, including SOC, TN, TP, and pH, significantly explained the stability of the soil aggregate. To summarize, chemical fertilizer combined with organic fertilizer positively affected the stability and nutrient accumulation of soil aggregates in greenhouse dryland. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 504 KiB

Open AccessArticle

Energy Balance, Productivity and Resource-Use Efficiency of Diverse Sustainable Intensification Options of Rainfed Lowland Rice Systems under Different Fertility Scenarios

by Teekam Singh, Ram Swaroop Bana, Bhabani Sankar Satapathy, Banwari Lal, Akshay Kumar Yogi and Raj Singh

Sustainability 2022, 14(6), 3657; https://doi.org/10.3390/su14063657 - 21 Mar 2022

Cited by 1 | Viewed by 1744

Abstract

Rice-based cropping systems (RBCS) are a kingpin of global food security and rice fallow is one of the largest (>14 m ha) RBCS. A three-year study was carried out to develop sustainable intensification options and efficient nutrient management protocols of RBCS with greater [...] Read more.

Rice-based cropping systems (RBCS) are a kingpin of global food security and rice fallow is one of the largest (>14 m ha) RBCS. A three-year study was carried out to develop sustainable intensification options and efficient nutrient management protocols of RBCS with greater water and energy productivity and more profits. Rice-lentil, rice-linseed and rice-rapeseed systems were tested in a split-plot design with nutrient management practices involving fertilizer levels (50%, 75% and 100% recommended fertilizer dose; RDF), green manuring with Sesbania (SGM) and rice residue incorporation (RRI). The results indicated that SGM produced significantly better rice productivity, enhanced 6.4–22.7% yield of succeeding crops and increased profits by ~20%. Application of 75 or 100% of RDF produced 24.5–30.3% higher grain yield of rabi crops. System intensification resulted in an additional rice equivalent yield (REY) of ~1–1.6 t ha⁻¹. SGM consumed relatively more energy (76,793 MJ ha⁻¹) but at the same time, resulted in higher energy output (182,657 MJ ha⁻¹), net energy (105,864 MJ ha⁻¹), energy intensity (1.68 MJ INR⁻¹) and human energy profitability (787) than the RRI. However, RRI recorded a higher energy ratio (2.42), energy productivity (0.082 kg MJ⁻¹) and energy profitability (1.42 kg MJ⁻¹). The rice-linseed cropping system resulted in greater system productivity, higher energy output (186,305 MJ ha⁻¹) and net energy (112,029 MJ ha⁻¹) than other systems. Overall, considering energy productivity, resource-use efficiency and profits, a rice-linseed system coupled with SGM and 75% RDF may be recommended as a sustainable intensification option in RBCS. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 251 KiB

Open AccessArticle

Optimizing the N Rate for Maize Forage to Balance Profits and N Ecological Stress

by Kun Han and Peng Liu

Agronomy 2022, 12(3), 718; https://doi.org/10.3390/agronomy12030718 - 16 Mar 2022

Cited by 1 | Viewed by 1588

Abstract

The N application used for the production of forage affects environment stress. The N application rate used for the production of the whole maize (Zea mays L.) plant (WMP) affects the produced feed and environment. We carried out a 2-year field experiment [...] Read more.

The N application used for the production of forage affects environment stress. The N application rate used for the production of the whole maize (Zea mays L.) plant (WMP) affects the produced feed and environment. We carried out a 2-year field experiment aiming to measure how N application rates affect WMP forage production, and estimated the impact on the environment. Five N application treatments (0, 100, 200, 300 and 400 kg N ha⁻¹) were included in our study. The results showed that N application improved forage yield, achieving a higher economic and ecological profit. After reaching a certain optimal rate, however, increasing the N rate further no longer increased the yield and quality of WMP forage, but instead greatly increased estimated N losses, thereby reducing ecological profits. The comprehensive benefit of the optimal N rate was ordered: the optimal N rate that maximized agronomic profit > that maximized economic profit > that maximized ecological benefit. The optimal N rate maximizing ecological profit was lower by 21% and 37% than that maximizing economic profit and forage yield, respectively. N application rates with the highest ecological profit (USD 2478 ha⁻¹ in 2017 and USD 2448 ha⁻¹ in 2018) were 248 and 245 kg N ha⁻¹, respectively, in 2017 and 2018. The optimized N rate that maximized ecological profit maintained the economic profit while reducing N fertilizer input and associated N losses; it also carried a lower economic and ecological cost due to estimated N losses. Ecological criteria, which combine economic profit and economic losses due to their environmental impact, are more efficient than agronomic or economic criteria when used to provide guidance for WMP forage production. Therefore, in WMP forage production, optimizing N application rate by ecological criteria could maintain a high forage yield and economic profit, but greatly reduce input costs and ecological stress, maximizing ecological profit. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

15 pages, 2374 KiB

Open AccessArticle

An Analysis on the Characteristics and Influence Factors of Soil Salinity in the Wasteland of the Kashgar River Basin

by Sheng Li, Li Lu, Yuan Gao, Yun Zhang and Deyou Shen

Sustainability 2022, 14(6), 3500; https://doi.org/10.3390/su14063500 - 16 Mar 2022

Cited by 9 | Viewed by 2132

Abstract

Clarifying the salt ion composition characteristics and the influence factors of soil salinization of the wasteland in the Kashgar River Basin is of high importance for saline land improvement and utilization in this region. We studied the characteristics and influence factors of soil [...] Read more.

Clarifying the salt ion composition characteristics and the influence factors of soil salinization of the wasteland in the Kashgar River Basin is of high importance for saline land improvement and utilization in this region. We studied the characteristics and influence factors of soil salinity in the wasteland of the Kashgar River Basin through classical statistics, principal component analysis and grey relational theory. The results showed that the total salt content had a T-shaped distribution pattern in the soil profile. As the most important ions, Cl⁻, Na⁺, and SO₄²⁻ have the characteristics of vertical differentiation from top to bottom in the soil profile. Correlation analysis showed that the total salt content was negatively correlated to the HCO₃⁻ content and positively correlated to other salt ions, The most correlated anions were SO₄²⁻ and Cl⁻. Na⁺, the most important cation, had the closest relationship with Cl⁻, followed successively by SO₄²⁻ and HCO₃⁻. Principal component analysis showed that SO₄²⁻, total salt content, Na⁺, Cl⁻, Mg²⁺, and Ca²⁺ could represent soil salinity status and salt ion composition, while HCO₃⁻ could represent soil alkalization status. The grey relational analysis indicated a differentiation in the intensity of influence of each factor on soil salinization at different depths. Except for groundwater burial depth and elevation, the relational degree between other influence factors and soil salt content decreased with depth. Our research findings offer important clues for understanding the soil salinity characteristics and influence factors of salinization in the wasteland of the Kashgar River Basin. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 5864 KiB

Open AccessArticle

The Comparison of Soil Agrochemical and Biological Properties in the Multi-Cropping Farming Systems

by Aušra Rudinskienė, Aušra Marcinkevičienė, Rimantas Velička, Robertas Kosteckas, Zita Kriaučiūnienė and Rimantas Vaisvalavičius

Plants 2022, 11(6), 774; https://doi.org/10.3390/plants11060774 - 14 Mar 2022

Cited by 5 | Viewed by 2108

Abstract

Multi-cropping systems play an important role in improving the quality of soil properties. A field experiment was carried at the Experimental Station of Vytautas Magnus University Agriculture Academy (Lithuania) in 2017 to 2019. The aim of the study was to compare agrophysical and [...] Read more.

Multi-cropping systems play an important role in improving the quality of soil properties. A field experiment was carried at the Experimental Station of Vytautas Magnus University Agriculture Academy (Lithuania) in 2017 to 2019. The aim of the study was to compare agrophysical and biological properties of the soil in the multi-cropping systems of sole (spring barley, spring wheat, pea, caraway), binary (spring barley–caraway, spring wheat–caraway, pea–caraway) and trinary (spring barley–caraway–white clover, spring wheat–caraway–white clover, pea–caraway–white clover) crops. In the second and the third years of caraway cultivation, when solely caraway was grown, the total nitrogen content was significantly lower than in binary and trinary crops (8.5% and 17.4%, respectively). The results indicated that the highest organic carbon content was in the third year of caraway cultivation in trinary crop when caraway was grown with peas and white clover. In the third year, the highest saccharase and urease activity was found in trinary crop where caraway was grown with spring barley and white clover. A strong positive correlation was observed between the content of saccharase and urease and the total nitrogen, organic carbon, and potassium available in the soil. The results of the study suggest that multi-cropping is important for soil conservation and the sustainability of agro-ecosystems. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 440 KiB

Open AccessArticle

Reduced Nitrogen Fertilizer Rates Maintained Raspberry Growth in an Established Field

by Qianwen Lu, Carol Miles, Haiying Tao and Lisa Wasko DeVetter

Agronomy 2022, 12(3), 672; https://doi.org/10.3390/agronomy12030672 - 10 Mar 2022

Cited by 5 | Viewed by 2613

Abstract

Optimizing nitrogen (N) fertilizer rates maintains good red raspberry (Rubus idaeus L.) production while alleviating environmental risks. Although raspberry growers in Washington are using the caneberry nutrient management guides derived from western Oregon, these guides may not be appropriate for other production [...] Read more.

Optimizing nitrogen (N) fertilizer rates maintains good red raspberry (Rubus idaeus L.) production while alleviating environmental risks. Although raspberry growers in Washington are using the caneberry nutrient management guides derived from western Oregon, these guides may not be appropriate for other production regions given the differences in climate, soil type, and crop productivity. However, limited research has been conducted to observe the impact of the N fertilizer rate on floricane red raspberry growth, yield, and fruit quality in Washington. The aim of this study is to evaluate the response of “Meeker” floricane red raspberries grown in northwest Washington, USA, to different N fertilizer rates in order to provide information for future local nutrient management guides. Treatments of urea (46% nitrogen (N)) were surface-applied to raised beds of established ‘Meeker’ raspberry plots at controls, low, medium, and high rates (0, 34, 67, and 101 kg N ha⁻¹, respectively) in 2019 and 2020. The experiment was arranged in a randomized complete block with three replications. Fruit yield and quality, plant growth and leaf tissue nutrient concentrations, and soil characteristics were evaluated. There were no N fertilizer rate treatment effects for the yield, fruit quality, plant growth, leaf tissue nutrient concentrations, and soil characteristics, except for fruit titratable acidity and soil ammonium (NH₄-N) concentrations. The lack of a plant response may be due to nutrients mineralized from soil organic matter (3.81–4.0%) and the utilization of plant nutrient reserves. Based on the results, the soil organic matter level and plant nutrient reserves should be considered when making nutrient management suggestions. Fertilizer costs as well as the potential for environmental pollution from excess fertilizers could be reduced through utilizing these two potential sources of nutrients. Furthermore, longer periods of research is warranted to understand how to adjust N fertilizer rates based on plant and soil characteristics while sustaining yields. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2872 KiB

Open AccessArticle

Taro (Colocasia esculenta (L.) Schott) Yields and Soil Chemical Properties Were Improved by Row-Surface Straw Mulching

by Zihui Zhu, Jiayu Qian, Yongxian Zhang, Hao Zhang, Haibo Dai, Zhiping Zhang, Minmin Miao and Jiezeng Jiang

Agronomy 2022, 12(3), 645; https://doi.org/10.3390/agronomy12030645 - 06 Mar 2022

Cited by 3 | Viewed by 4997

Abstract

The rational use of a large amount of straw produced from grain fields is an important issue in major grain-producing areas. On the other hand, due to the long-term preferential applications of chemical fertilizers, soil organic carbon (SOC) content, soil fertility and organic [...] Read more.

The rational use of a large amount of straw produced from grain fields is an important issue in major grain-producing areas. On the other hand, due to the long-term preferential applications of chemical fertilizers, soil organic carbon (SOC) content, soil fertility and organic matter levels have decreased, and the soil physical-chemical properties have deteriorated in protected agricultural facilities. In this study, a wet crop, taro (Colocasia esculenta (L.) Schott) and the straw of two main crops [wheat (Triticum aestivum L.) and rice (Oryza sativa L.)] were selected to investigate the effect of row-surface straw mulching on taro yields and soil chemical properties. The results showed that nearly all wheat straw and 74% of rice straw decomposed in one season under wet conditions. Straw mulching significantly increased the taro yield, increased the levels of SOC, soil rapid available nitrogen, phosphorus and potassium, and improved the activities of sucrase and phosphatase in the soil. We conclude that row-surface straw mulching t of wet crops could not only improve the soil properties and crop yields in the protected facility but could also consume considerable straw (wheat: 14,250 kg/ha, rice: 111,00 kg/ha), and the method applied in other areas with similar conditions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 3118 KiB

Open AccessEditor’s ChoiceArticle

Influence of Climate Variability and Soil Fertility on the Forage Quality and Productivity in Azorean Pastures

by Catarina D. Melo, Cristiana S. A. M. Maduro Dias, Sophie Wallon, Alfredo E. S. Borba, João Madruga, Paulo A. V. Borges, Maria T. Ferreira and Rui B. Elias

Agriculture 2022, 12(3), 358; https://doi.org/10.3390/agriculture12030358 - 02 Mar 2022

Cited by 16 | Viewed by 3094

Abstract

This work aimed to determine and compare the effect of elevation and season on the productivity and the nutritive value of pastures in the Azores (Terceira Island). Forage was collected and analysed for dry matter (DM), crude protein (CP), neutral detergent fibre (NDF), [...] Read more.

This work aimed to determine and compare the effect of elevation and season on the productivity and the nutritive value of pastures in the Azores (Terceira Island). Forage was collected and analysed for dry matter (DM), crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), ether extract (EE), mineral ash (Ash), dry matter digestibility (DMD) and organic matter digestibility (OMD). The net productivity (NP) was higher in the low elevation pasture A (1.80 g m⁻²), lower in pasture B (0.98 g m⁻²) and peaked in the winter in both pastures A (3.57 g m⁻²) and B (2.33 g m⁻²) and during the summer in the high elevation pasture C (2.15 g m⁻²). The soil chemical proprieties varied significantly among the three pastures. The highest soil pH, available P, K, Ca and Mg were recorded in pasture A. Positive correlations were observed between all soil parameters analysed and NP, except for the OM content. The DM, PB and EE changed significantly with elevation, while all nutritive parameters (except CP, EE and Ash) increased significantly along the growth season. Environmental factors influenced the nutritive parameters and productivity, suggesting that climate change might have significant impacts on forage production and quality. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 11745 KiB

Open AccessArticle

Non-Composted Chinaberry (Melia azedarach L.) Sawdust Mixtures as Growth Medium for Okra (Abelmoschus esculentus (L.) Moench)

by Muhammad Yasin, Hassan Noorani, Farhan Anwar, Manahil Siddiqui, Muhammad Ehsan Safdar and Christian Andreasen

Agriculture 2022, 12(3), 354; https://doi.org/10.3390/agriculture12030354 - 01 Mar 2022

Cited by 4 | Viewed by 3182

Abstract

Sawdust as a soilless growth substrate for plants is becoming popular in greenhouse production. However, fresh sawdust often requires time for decomposition before it is ready for use as a growth substrate. We studied whether amendments of banana peels (as a source of [...] Read more.

Sawdust as a soilless growth substrate for plants is becoming popular in greenhouse production. However, fresh sawdust often requires time for decomposition before it is ready for use as a growth substrate. We studied whether amendments of banana peels (as a source of potassium), eggshells (as a source of calcium), and urea (as a source of nitrogen) in non-composted fresh chinaberry (Melia azedarach) sawdust could enhance its potential as a growth medium. In two pot experiments, the growth of okra (Abelmoschus esculentus (L.) Moench) was evaluated using mixtures of non-composted M. azedarach sawdust. The treatments were: (T₁) 100% soil (control) (vol/vol); (T₂) 100% M. azedarach sawdust (vol/vol); (T₃) 80% M. azedarach sawdust +20% banana peel (vol/vol); (T₄) 60% M. azedarach sawdust +20% banana peel +20% eggshell (vol/vol); and (T₅) 60% M. azedarach sawdust +20% banana peel +20% eggshell (vol/vol) +91 kg N ha⁻¹ (urea). There was no significant difference between the treatments regarding seed germination and okra emergence, but leaf area, chlorophyll content index, plant biomass, number of pods per plant⁻¹, fresh pods, and dry weight were significantly lower in pots with fresh sawdust mixtures. Organic amendments of banana peels and eggshells improved the sawdust substrate. Adding a further 91 kg N hectare⁻¹ improved the growth but was insufficient to produce the same yield of okra as in non-fertilized sandy clay loam soil. We cannot exclude that non-composted M. azedarach sawdust may be a potential growth substrate for okra, but the amendments added were not enough to obtain the same yields as when okra was grown in soil. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 619 KiB

Open AccessArticle

The Effect of Meat and Bone Meal (MBM) on Phosphorus (P) Content and Uptake by Crops, and Soil Available P Balance in a Six-Year Field Experiment

by Aleksandra Załuszniewska and Anna Nogalska

Sustainability 2022, 14(5), 2855; https://doi.org/10.3390/su14052855 - 01 Mar 2022

Cited by 6 | Viewed by 5360

Abstract

The aim of a six-year field experiment conducted in north-eastern (NE) Poland was to determine the effect of meat and bone meal (MBM) on phosphorus (P) content and uptake by different crops, soil available P balance, and soil pH. Five treatments were established: [...] Read more.

The aim of a six-year field experiment conducted in north-eastern (NE) Poland was to determine the effect of meat and bone meal (MBM) on phosphorus (P) content and uptake by different crops, soil available P balance, and soil pH. Five treatments were established: (1) zero-fert; (2) inorganic NPK; (3) 1.0 t ha⁻¹ MBM; (4) 1.5 t ha⁻¹ MBM; and (5) 2.0 t ha⁻¹ MBM. Constant nitrogen (N) and potassium (K) rates and increasing P rates (0.0; 45; 68 and 90 kg ha⁻¹) were applied. The lowest dose of MBM, which supplied 45 kg P ha⁻¹ each year, was sufficient to meet the P requirements of silage maize, winter wheat, and winter oilseed rape to the same extent as mineral P fertilizer at the equivalent rate. The uptake, balance, and utilization of P by plants were comparable in both treatments. Phosphorus applied each year at high rates (68 and 90 kg ha⁻¹) with two higher MBM doses contributed to excessive P accumulation in soil; therefore, MBM should not be applied at doses exceeding 1.5 t ha⁻¹ to crops grown in acidic soils. Soil pH was not significantly affected by MBM. MBM can replace conventional mineral P fertilizers in crop cultivation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1974 KiB

Open AccessArticle

The Effect of Nitrogen Fertilizer and Water Supply Levels on the Growth, Antioxidant Compounds, and Organic Acids of Baby Lettuce

by Khayelihle Ncama and Nkanyiso Justice Sithole

Agronomy 2022, 12(3), 614; https://doi.org/10.3390/agronomy12030614 - 28 Feb 2022

Cited by 2 | Viewed by 2792

Abstract

Applications of solutions with various organic acids have been widely demonstrated as effective disinfectants on lettuce. However, agronomic techniques of improving the concentration of internal organic acids in lettuce are not well investigated. Hereon, changes in growth, antioxidants, and organic acids of baby [...] Read more.

Applications of solutions with various organic acids have been widely demonstrated as effective disinfectants on lettuce. However, agronomic techniques of improving the concentration of internal organic acids in lettuce are not well investigated. Hereon, changes in growth, antioxidants, and organic acids of baby lettuce (Lactuca sativa L. var. longifolia) resulting from different levels of nitrogen fertilizer (0.10, 0.14, 0.18, or 0.22 g/5 kg soil) and water supply (300, 600, or 900 mL) were investigated. The pot experiment was conducted under a net house at North-West University (Mafikeng Campus), South Africa. Data on growth parameters (number of leaves and leaf area) and chlorophyll concentration were sampled weekly until leaf organic acids (citric, malic, and tartaric), total antioxidant compounds (TAO), as well as dry matter content, were measured at harvest. Reducing the amount of water supplied to baby lettuce significantly (p < 0.05) increased the chlorophyll concentration, leaf area, TAO, citric acid, and malic acid. The number of leaves and the leaf tartaric acid concentrations were increased by increasing the treatment levels. It was conclusive that decreasing water supply increases the organic acids regardless of the nitrogen level. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 1153 KiB

Open AccessArticle

Improving Rabbiteye Blueberry Performance in a Calcareous Soil by Growing Plants in Pits Filled with Low-CaCO₃ Growth Media

by Guy Tamir, Dagan Eli, Shmuel Zilkah, Asher Bar-Tal and Nir Dai

Agronomy 2022, 12(3), 574; https://doi.org/10.3390/agronomy12030574 - 25 Feb 2022

Cited by 2 | Viewed by 1746

Abstract

Calcareous soils are not suitable for blueberry cultivation. Our aim was to improve the performance of blueberry plants in calcareous soils by using pits filled with growth media in combination with high levels of RNH₄⁺ (proportion of N-NH₄⁺ among [...] Read more.

Calcareous soils are not suitable for blueberry cultivation. Our aim was to improve the performance of blueberry plants in calcareous soils by using pits filled with growth media in combination with high levels of RNH₄⁺ (proportion of N-NH₄⁺ among the total applied N). Rabbiteye blueberry (Vaccinium virgatum Ait. cv. Ochlockonee) plants were grown in pits filled with a tuff/peat mixture (TP), a sandy soil (S) or a calcareous (CC), in full factorial combination with three levels of RNH₄⁺: 33%, 66% or 100%. The two higher RNH₄⁺ treatments decreased the pH of the low-CaCO₃ (S) and no-CaCO₃ (TP) media to ≤6.0 over 250 days of fertilization, but did not affect the pH of the CC soil over 650 days. Plant performance was superior in the TP and S media, as compared to the CC soil. The type of growth medium was the dominant factor accounting for the improved plant performance. The plants were sensitive to Mn deficiency in leaves during the spring period. The current results suggest that growing blueberry in pits filled with good aeration and low pH buffering capacity medium in combination with a high level of RNH₄⁺ is a positive approach for its cultivation in calcareous soils. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 723 KiB

Open AccessReview

Effects of Liming on Soil Properties and Its Roles in Increasing the Productivity and Profitability of the Oil Palm Industry in Malaysia

by Md Shawon Mahmud and Khim Phin Chong

Agriculture 2022, 12(3), 322; https://doi.org/10.3390/agriculture12030322 - 23 Feb 2022

Cited by 19 | Viewed by 11284

Abstract

As global demand for edible oil increases, palm oil-producing countries in Southeast Asia are experiencing a rapid expansion of agricultural land for industrial oil palm cultivation by converting existing agricultural lands and some tropical rainforests; however, soil acidity and nutrient depletion are two [...] Read more.

As global demand for edible oil increases, palm oil-producing countries in Southeast Asia are experiencing a rapid expansion of agricultural land for industrial oil palm cultivation by converting existing agricultural lands and some tropical rainforests; however, soil acidity and nutrient depletion are two major constraints in oil palm cultivation in the tropics. Several factors may cause soil acidification, including natural processes, industrial pollutants and extensive agricultural production. Soil acidity increases the leaching of many essential plant nutrient elements and the availability of toxic elements by modifying various geochemical and biological reactions in the soil. Even though acidic soil is less fertile, the productivity of tropical soil is among the highest in the world once the chemical constraints are removed by applying a sufficient quantity of lime and fertilizers. Lime is a widely used alkali to improve soil fertility by retaining nutrients, increasing soil biota, decreasing heavy-metal availability and potentially achieving resistance against Ganoderma disease at oil palm estates. Liming materials are not simple compounds with consistent chemical properties; thus, selecting the appropriate lime must be based on soil type and price compared to the products neutralizing value, composition, and fineness. Since the primary aim of liming is to improve soil pH, numerous reviews have been reported on the impacts of soil acidification, nutrient deficiencies and heavy-metal toxicity; however, no extensive review has been published that discusses the effects of liming on oil palm growth and yield. It is not enough to emphasize just soil impacts alone, and a thorough assessment must also be given on crops (oil palm) and soil biodiversity. This review synthesizes current understanding and introduces a holistic approach to provide insights into the far-reaching effects liming has on the biogeochemical properties of tropical soil and oil palm crops. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 881 KiB

Open AccessArticle

Pecan (Carya illinoinensis) and Dairy Waste Stream Utilization: Properties and Economics of On-Farm Windrow Systems

by Emily F. Creegan, Robert Flynn, Greg Torell, Catherine E. Brewer, Dawn VanLeeuwen, Ram N. Acharya, Richard J. Heerema and Murali Darapuneni

Sustainability 2022, 14(5), 2550; https://doi.org/10.3390/su14052550 - 23 Feb 2022

Cited by 2 | Viewed by 1564

Abstract

Improper management of organic waste can lead to unnecessary carbon dioxide and methane emissions, and groundwater contamination. In this study, organic waste materials from two of New Mexico’s (U.S.A.) top agricultural industries, pecan (Carya illinoinensis) and dairy cattle dairy manure, were [...] Read more.

Improper management of organic waste can lead to unnecessary carbon dioxide and methane emissions, and groundwater contamination. In this study, organic waste materials from two of New Mexico’s (U.S.A.) top agricultural industries, pecan (Carya illinoinensis) and dairy cattle dairy manure, were used to evaluate the feasibility of an on-farm compost program. Pecan woody residues (P) served as the primary carbon source; regional cattle dairy manure (M) served as the primary nitrogen source. Additional (A) inputs from a compost consulting company (PM/A) and green waste from community landscaping and on-farm harvested legumes (PMG/A) were employed, both of which required additional labor and material inputs. Finished composts were analyzed for selected macro, secondary and micronutrients, pH, sodium adsorption ratio (SAR), electrical conductivity (EC), total carbon (TC) and organic matter (OM) content, bulk density (b_d), and microbial biomass. The PM alone treatment showed similar or significantly higher amounts of macro, secondary and micronutrients compared to the PM/A and PMG/A treatments. Total microbial biomass and total salinity were highest for the PM treatment. The total cost of the PM treatment was around 1/6 of the cost of the lowest-cost addition compost production scheme, indicating that simpler, lower-input production methods may be more advantageous for on-farm compost program development. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 2556 KiB

Open AccessFeature PaperArticle

Effect of Clay Mineralogy and Soil Organic Carbon in Aggregates under Straw Incorporation

by Bin Xue, Li Huang, Xiaokun Li, Jianwei Lu, Ruili Gao, Muhammad Kamran and Shah Fahad

Agronomy 2022, 12(2), 534; https://doi.org/10.3390/agronomy12020534 - 21 Feb 2022

Cited by 24 | Viewed by 3488

Abstract

The interaction between soil organic carbon (SOC) and clay minerals is a critical mechanism for retaining SOC and protecting soil fertility and long-term agricultural sustainability. The SOC composition and minerals speciation in clay fractions (<2 μm) within soil aggregates under straw removed (T) [...] Read more.

The interaction between soil organic carbon (SOC) and clay minerals is a critical mechanism for retaining SOC and protecting soil fertility and long-term agricultural sustainability. The SOC composition and minerals speciation in clay fractions (<2 μm) within soil aggregates under straw removed (T) and straw incorporation (TS) conditions were analyzed by X-ray diffraction, Fourier transform infrared spectra and X-ray photoelectron spectroscopy. The TS treatment promoted enrichment of clay in aggregates. The TS increased the contents of SOC (27.0–86.6%), poorly crystalline Fe oxide (Fe_o), and activity of Fe oxides (Fe_o/Fe_d); whereas, it reduced the concentrations of free Fe oxide (Fe_d) in the clay fractions within aggregates. Straw incorporation promoted the accumulation of aromatic-C and carboxylic-C in the clay fraction within aggregates. The relative amount of hydroxy-interlayered vermiculite, aliphatic-C, and alcohol-C in the clay fractions within the macroaggregates was higher than that microaggregates, whereas the relative amounts of illite, kaolinite, Fe(III), and aromatic-C had a reverse tendency. The hydroxy-interlayered vermiculite in clay fractions showed positive correlation with the amounts of C–C(H) (r = 0.93) and C–O (r = 0.96 *, p < 0.05). The concentration of Feo and Feo/Fed ratio was positively correlated with the amounts of C=C and C(O)O content in clay within aggregates. Long-term straw incorporation induced transformation of clay minerals and Fe oxide, which was selectively stabilized straw-derived organic compounds in clay fractions within soil aggregates. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 2955 KiB

Open AccessArticle

Effects of Shallow Groundwater Depth and Nitrogen Application Level on Soil Water and Nitrate Content, Growth and Yield of Winter Wheat

by Yingjun She, Ping Li, Xuebin Qi, Wei Guo, Shafeeq Ur Rahman, Hongfei Lu, Cancan Ma, Zhenjie Du, Jiaxin Cui and Zhijie Liang

Agriculture 2022, 12(2), 311; https://doi.org/10.3390/agriculture12020311 - 21 Feb 2022

Cited by 7 | Viewed by 2410

Abstract

The large amount of nitrogen application on the North China Plain has caused a serious negative impact on the sustainable development of regional agriculture and ecological environmental protection. Our aim was to explore the effects of nitrogen fertilization rate and groundwater depth on [...] Read more.

The large amount of nitrogen application on the North China Plain has caused a serious negative impact on the sustainable development of regional agriculture and ecological environmental protection. Our aim was to explore the effects of nitrogen fertilization rate and groundwater depth on growth attributes, soil-water and soil-fertilizer contents, and the winter wheat yield. Experiments were carried out in micro-lysimeters at groundwater depths of 60, 90, 120, and 150 cm on the basis of 0, 150, 240, and 300 kg/ha nitrogen fertilization rates in the growth season for winter wheat. Results showed that plant height, leaf area index, soil plant analysis development, and yield without nitrogen application increased significantly with increases in groundwater depth. The optimal groundwater depths for growth attributes and yield were 60–120 cm and tended to be shallower with added nitrogen application. Soil moisture was lowered significantly with groundwater depth, adding a nitrogen application reduced soil moisture, and excessive nitrogen input intensified soil drought. Nitrate-N accumulation at the 120–150 cm depths was significantly higher than that at the 60–90 cm depths, and a 300 kg/ha (traditional nitrogen application rate) treatment was 6.7 times greater than that of 150 kg/ha treatment and increased by 74% more than that of the 240 kg/ha treatment at 60–150 cm depth. Compared with the yield of the 300 kg/ha rate, the yield of the 240 kg/ha rate had no significant difference, but the yield increased by 3.90% and 11.09% at the 120 cm and 150 cm depths. The growth attributes and yield of winter wheat were better, and the soil nitrate-N content was lower, when the nitrogen application rate was 240 kg/ha. Therefore, it can be concluded that nitrogen application can be reduced by 20% on the North China Plain. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 1479 KiB

Open AccessArticle

Effects of Integrated and Organic Management on Strawberry (cv. Camarosa) Plant Growth, Nutrition, Fruit Yield, Quality, Nutraceutical Characteristics, and Soil Fertility Status

by Peter Anargyrou Roussos, Athanassios Triantafillidis, Evaggelos Kepolas, Panagiotis Peppas, Anastassia Piou, Maria Zoti and Dionisios Gasparatos

Horticulturae 2022, 8(2), 184; https://doi.org/10.3390/horticulturae8020184 - 21 Feb 2022

Cited by 7 | Viewed by 3697

Abstract

Strawberry plants (cv. Camarosa) were cultivated under organic (ORG) and integrated management (INT) practices to assess possible differences in plant growth, fruit production and quality, soil fertility, and plant nutrition. Two integrated fertilizer schemes were used, differentiating based on the origin of the [...] Read more.

Strawberry plants (cv. Camarosa) were cultivated under organic (ORG) and integrated management (INT) practices to assess possible differences in plant growth, fruit production and quality, soil fertility, and plant nutrition. Two integrated fertilizer schemes were used, differentiating based on the origin of the major organic fertilizer used, i.e., chicken manure (I-ACT) versus fermented fungal biomass (I-AGR). Plant growth was higher under I-ACT treatment, whereas leaf area did not differ among treatments. The two integrated schemes resulted in higher fruit production. The organoleptic characteristics of the fruits did not differ, and this was also confirmed by a taste panel. The antioxidant capacity and flavanol concentration of organically produced fruits were higher, as well as fruit carbohydrate and total organic acid concentration. Leaf nitrogen concentration was higher under I-ACT, followed by ORG. I-ACT resulted in high leaf potassium concentration, as well as iron and manganese (together with I-AGR). Under ORG management, soil EC was found to be lower, whereas soil available phosphorus concentration was highest. Discriminant analysis taking into account fruit quality and phytochemical properties distinguished ORG management from the two integrated management practices, and when soil properties and leaf nutrient concentration were considered; all three systems were separated, indicating that the type of fertilizers used plays a significant role. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2843 KiB

Open AccessArticle

Comparative Analysis of the Effects of Plastic Mulch Films on Soil Nutrient, Yields and Soil Microbiome in Three Vegetable Fields

by Xi Shan, Wei Zhang, Zhongliang Dai, Jianbin Li, Weiwei Mao, Fangwei Yu, Jinjun Ma, Shenyun Wang and Xiaoping Zeng

Agronomy 2022, 12(2), 506; https://doi.org/10.3390/agronomy12020506 - 17 Feb 2022

Cited by 13 | Viewed by 2726

Abstract

Plastic film mulching is a common practice to increase vegetable yields. However, the effects of plastic mulch films on different vegetable fields remain largely unknown. In the current study, biodegradable mulch films (BDMs) and polyethylene mulch films (PEMs) were used to explore their [...] Read more.

Plastic film mulching is a common practice to increase vegetable yields. However, the effects of plastic mulch films on different vegetable fields remain largely unknown. In the current study, biodegradable mulch films (BDMs) and polyethylene mulch films (PEMs) were used to explore their effects on three vegetable fields (broccoli, chili pepper and garlic). Compared with bare soil, both BDMs and PEMs could effectively maintain higher exchangeable potassium contents in rhizosphere soil, and significantly increase various soil properties and microbial abundance both in rhizosphere and non-rhizosphere soils. In terms of yields, the treatments of BDMs and PEMs effectively increased broccoli, chili pepper and garlic yields by 17.6–19.0%, 21.3–23.3% and 26.0–29.5%, respectively, when compared with the bare soil. Our initial characterization provided insights into the effects of BMDs and PEMs on soil properties, yields and diversity of rhizosphere and non-rhizosphere microbial communities in three vegetable fields. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 270 KiB

Open AccessArticle

Effect of Eucalyptus-Wood-Based Compost Application Rates on Avocado (Persea americana Mill) Foliar Nutrient Content and Fruit Yield

by Mmatshaka Phillimon Mohale, Alen Manyevere, Cosmas Parwada and Mussie Zerizghy

Agronomy 2022, 12(2), 477; https://doi.org/10.3390/agronomy12020477 - 14 Feb 2022

Cited by 3 | Viewed by 2434

Abstract

Background: The effects of different fertilizer types and their application rates on leaf nutrient content and avocado yield are unclear. An evaluation of eucalyptus-wood-based compost applied at 0, 5, 10, and 15 t ha⁻¹ year⁻¹ on foliar nutrient content, yield, and [...] Read more.

Background: The effects of different fertilizer types and their application rates on leaf nutrient content and avocado yield are unclear. An evaluation of eucalyptus-wood-based compost applied at 0, 5, 10, and 15 t ha⁻¹ year⁻¹ on foliar nutrient content, yield, and fruit size distribution (%) was completed at Mooketsi and Politsi, Limpopo Province, South Africa, from 2016 to 2018. Methods: A completely randomized block design with three replicates was used. Data were collected annually, and fruit size was classified as classes; 1 (>275 g), 2 (197–274 g), 3 (148–196 g), and 4 (0–147 g). Results: Leaf N, P, K, Ca, Mg, Fe, Mn, Na, Cu, and Zn, fruit yield and size distribution (%) were significantly (p < 0.05) affected by compost quantity and proportionally increased with application rates in each year. Compost had cumulative effects on the measured parameters; the highest values were recorded in 2018 under a 15 t ha⁻¹ application rate, which corresponded to the highest yield (19.6 t ha⁻¹) and the largest proportion of fruits in class 1. Conclusions: The ≥10 t ha⁻¹ year⁻¹ application rate can be used, though the compost saturation levels of the soils should be determined to avoid possible danger of nutrient toxicity if high application rates are continuously used for >3 years. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

18 pages, 746 KiB

Open AccessArticle

Long-Term Impacts of Different Cropping Patterns on Soil Physico-Chemical Properties and Enzyme Activities in the Low Land Plain of North China

by Florence Nyambura Gikonyo, Xinliang Dong, Peter Semba Mosongo, Kai Guo and Xiaojing Liu

Agronomy 2022, 12(2), 471; https://doi.org/10.3390/agronomy12020471 - 14 Feb 2022

Cited by 13 | Viewed by 2678

Abstract

Various cropping patterns are extensively used on the North China Plain, which greatly alter various soil properties. Although these soil properties respond differently to the different cropping patterns, little is known about the possible effects of cropping patterns on desalinized soils. To assess [...] Read more.

Various cropping patterns are extensively used on the North China Plain, which greatly alter various soil properties. Although these soil properties respond differently to the different cropping patterns, little is known about the possible effects of cropping patterns on desalinized soils. To assess the effects of the different cropping patterns on soil properties and enzyme activities, a long-term field experiment was conducted at the Nanpi Agro-Ecological Station in Hebei Province, China. The cropping patterns under study were the single-cropping patterns of winter wheat (Triticum aestivum L.), spring maize (Zea mays), and spring cotton (Gossypium hirsutum), and the double-cropping pattern of winter wheat–summer maize (WW–SM), which is the predominant cropping pattern on the North China Plain. Soil samples were collected at a depth of 0–100 cm, depending on the soil properties. Our results indicated that soil available phosphorous (P) and available potassium (K) concentrations at 0–20 cm were greater than those of the subsurfaces. Soil organic matter declined with depth, and WW–SM had the highest amount in the deep levels. The WW–SM cropping pattern also generally showed greater levels of enzyme activities than did the single-cropping patterns, proving that diverse crops can enhance enzyme activities. Soil pH generally increased with depth despite there being no significant differences between the cropping patterns. No significant effects were observed on soil electrical conductivity (EC). However, EC generally increased with depth in spring cotton and winter wheat and declined in spring maize and WW–SM. Winter wheat had a significant aggregate size (<0.053 mm) at 20–40 cm depth and generally showed the lowest amount of nutrients. This study suggests that a fallow period allows the soil to regenerate its structure, whereas WW–SM enhances high soil organic matter in the deep soil layers and promotes increased soil enzyme activities. This indicates that crop rotation could sustainably exploit soil resources without reducing fertility over a long period. There is a need to incorporate different soil management practices for single-cropping patterns to increase their productivity, especially in spring maize, whose organic matter declined the most. Our results also show a need to diversify to different crop rotations to utilize their benefits and enhance soil productivity while increasing crop output. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 587 KiB

Open AccessArticle

Challenges to Adoption of Improved Legume Varieties: A Gendered Perspective

by Bezaiet Dessalegn, Woinishet Asnake, Abiro Tigabie and Quang Bao Le

Sustainability 2022, 14(4), 2150; https://doi.org/10.3390/su14042150 - 14 Feb 2022

Cited by 7 | Viewed by 2299

Abstract

Limited availability and access to seeds of improved varieties are often blamed for the low adoption of legume-based rotations. In this paper, we use a case study of chickpea and lentil production in Ethiopia and a gendered lens to identify other determinants of [...] Read more.

Limited availability and access to seeds of improved varieties are often blamed for the low adoption of legume-based rotations. In this paper, we use a case study of chickpea and lentil production in Ethiopia and a gendered lens to identify other determinants of farmers’ decisions for the adoption of improved legume varieties. Mixed methods were used to collect sex and age disaggregated data through 360 household surveys, 11 focus group discussions, and 8 key informant interviews. The analysis focused on key adoption parameters, including access to land, labor, improved seed varieties, fertilizers, pesticides, agriculture information, and credit. The main challenges identified include: differential access to timely and adequate seeds of improved varieties, quality fertilizers, and pesticides; availability of credit at an affordable interest rate; and equitable access to information. As compared to men, we found women’s access to these resources to be low and women’s cost production to be relatively high. Farmland remains a main constraint for the youth. Farmers responded to the challenges by recycling seeds and mono-cropping lentils, despite declining soil and crop productivity, and increased occurrence of pests and diseases. In the case of chickpea, we found that cultural norms also discouraged the adoption of the improved variety. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 1721 KiB

Open AccessArticle

Crop Residue Return Rather Than Organic Manure Increases Soil Aggregate Stability under Corn–Soybean Rotation in Surface Mollisols

by Yang Xiao, Meng Zhou, Yansheng Li, Xingyi Zhang, Guanghua Wang, Jian Jin, Guangwei Ding, Xiannan Zeng and Xiaobing Liu

Agriculture 2022, 12(2), 265; https://doi.org/10.3390/agriculture12020265 - 13 Feb 2022

Cited by 6 | Viewed by 2619

Abstract

Fertilization practices change soil organic carbon content and distribution, which is relevant to crop rotation and soil aggregates. However, how fertilization management under corn–soybean rotation affects soil organic carbon and aggregate stability at different soil depths in Mollisols is unclear. The effects of [...] Read more.

Fertilization practices change soil organic carbon content and distribution, which is relevant to crop rotation and soil aggregates. However, how fertilization management under corn–soybean rotation affects soil organic carbon and aggregate stability at different soil depths in Mollisols is unclear. The effects of 6–yr fertilization under corn–soybean rotation on aggregate stability, soil organic carbon content and storage, and size distribution in soil aggregates were investigated. Five different fertilization practices were carried out in 2013: corn and soybean without fertilizer; corn with chemical fertilizer, soybean without fertilizer; corn with chemical fertilizer, soybean without fertilizer, returning the corn and soybean residues; corn and soybean with chemical fertilizer; and corn with chemical fertilizer, soybean with farmyard manure. Compared with corn and soybean without fertilizer, returning the corn and soybean residues increased bulk SOC content, and enhanced mean weight diameter and geometric mean diameter values at 0–10 cm because of increased water–stable aggregates (WSA) larger than 2 mm proportion and decreased WSA_<0.053mm proportion. Simultaneously, corn with chemical fertilizer and soybean with farmyard manure increased bulk soil organic carbon content but reduced mean weight diameter and geometric mean diameter values at 0–20 cm due to increased WSA_<0.053mm proportion and decreased WSA_>2mm proportion. Altogether, the application of consecutive returning crop residues and chemical fertilizer in alternate years is the most favorable approach for soil organic carbon accumulation and aggregate stability at 0–10 cm under corn–soybean rotation in Mollisols. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1665 KiB

Open AccessArticle

The Negative Effects of High Rates of Biochar on Violas Can Be Counteracted with Fertilizer

by Abishkar Regmi, Sukhbir Singh, Naima Moustaid-Moussa, Cade Coldren and Catherine Simpson

Plants 2022, 11(4), 491; https://doi.org/10.3390/plants11040491 - 11 Feb 2022

Cited by 10 | Viewed by 2359

Abstract

Increasing costs and environmental issues regarding excessive use of peat moss is impacting the horticultural industry. Biochar is a valuable substrate additive that has the potential to reduce the use of peatmoss in greenhouse production. However, its varying effects on ornamentals requires that [...] Read more.

Increasing costs and environmental issues regarding excessive use of peat moss is impacting the horticultural industry. Biochar is a valuable substrate additive that has the potential to reduce the use of peatmoss in greenhouse production. However, its varying effects on ornamentals requires that individual species and cultivars of crops must be evaluated to determine the threshold for benefits. Viola cornuta is a high value ornamental crop; however, information on how different rates of biochar rates affect productivity and physiology of Viola cultivars in container production is not known. To determine if biochar rates could increase the productivity of Viola, we mixed a peat-based substrate with 10, 25, and 50% (w:w) hardwood biochar in two studies on four cultivars. Without fertilizers, 10 and 25% biochar improved plant biomass, growth, root length, and flowering, but 50% biochar was found to have negative effects on plant growth and flowering. Cultivars varied in their response to biochar rates. When fertilizer was applied in the second experiment, biochar rates did not impact growth parameters or flowering. These results suggest that up to 25% biochar can be used in Viola production without detrimental impacts. However, 50% biochar can be used with the addition of fertilizer without negatively affecting plant growth. Biochar can have a short-term impact on the growth characteristics of Viola plants in container production, but fertilization and growing period of Viola may influence these effects. These results indicate that biochar could be the suitable replacement for peat moss, with up to 50% biochar rate in Viola production reducing the environmental and economic burden for peat moss. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2844 KiB

Open AccessArticle

Understanding the Priming Effect and the Routes and Stocks of C in Incubated Soil with Residue Inputs

by Risely Ferraz-Almeida

Horticulturae 2022, 8(2), 154; https://doi.org/10.3390/horticulturae8020154 - 11 Feb 2022

Cited by 1 | Viewed by 1690

Abstract

The priming effect is a strong short-term change of organic matter decomposition that can accelerate or slow residue decomposition, and release or immobilize a large amount of carbon (C) and nitrogen (N) in soil. Our goal here was to (i) monitor the influence [...] Read more.

The priming effect is a strong short-term change of organic matter decomposition that can accelerate or slow residue decomposition, and release or immobilize a large amount of carbon (C) and nitrogen (N) in soil. Our goal here was to (i) monitor the influence of residue additions in stocks of C and N in residues and soil (ii) and identify the main routes of C stabilization and the priming effect in soil. An incubation study was run with residue additions of high C:N (brachiaria and sugarcane) and low C:N (soybean) in soil. CO₂ emissions, stocks of C (humic substance; labile C and C mic) and N (soil and residues) were monitored for 50 days, and the priming effect and route of C were calculated. Results showed that after incubation the final stocks of humin increased (31%), while there were reductions of humic (54%) and fulvic acids (42%). The stocks of soil total C and N were constant, while the residue C was decreased. The residues with high C:N immobilized N, while there was a decrease of N in residues with low C:N. There was a positive priming effect and a C stabilization route concentrated from C mic to humic substances with the addition of low C:N, while inputs of high C:N diversified the C stabilization routes from C mic or labile C to humic substances. The C routes were intense because the study was run in control conditions with a loam soil and adequate conditions of water, oxygen, and temperature. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 2347 KiB

Open AccessArticle

Standing Biomass, Dry-Matter Production, and Nutrient Demand of Tenera Oil Palm

by Cheah See Siang, Siti Aishah Abd Wahid and Christopher Teh Boon Sung

Agronomy 2022, 12(2), 426; https://doi.org/10.3390/agronomy12020426 - 09 Feb 2022

Cited by 4 | Viewed by 2873

Abstract

Recent advances in oil-palm breeding and agronomic practices may have influenced the dry-matter production and nutrient demand of tenera oil palm since the last comprehensive studies published some three decades ago. This has raised concerns, since updated knowledge of nutrient requirements at various [...] Read more.

Recent advances in oil-palm breeding and agronomic practices may have influenced the dry-matter production and nutrient demand of tenera oil palm since the last comprehensive studies published some three decades ago. This has raised concerns, since updated knowledge of nutrient requirements at various stages of oil palm growth is essential for formulating fertilizer recommendations that meet agronomic, economic, and environmental objectives. We therefore filled in this knowledge gap with the objective to quantify the standing biomass, dry-matter production, and nutrient demand of tenera oil palm of different ages, grown under current agronomic practices. Tenera palms were sampled at 12, 29, 48, 88, 133, 209, and 238 months since nursery planting and separated into spear leaves, leaflets, rachis, petiole, leaf bases, cabbage, trunk, bole, and roots attached to bole for determination of dry weights and nutrient contents. Fruit bunches were harvested, with dry weights and nutrient contents of ripe bunches determined. Annual dry-matter production was calculated from dry weights of different plant parts, and together with nutrient concentrations determined in these plant parts and fruit bunches, annual nutrient demand was calculated. Excluding roots, the total standing vegetative biomass increased almost linearly from 1.3 kg palm⁻¹ at 12 months old to 808.6 kg palm⁻¹ at 238 months old. Whole-palm dry-matter production increased with palm age but at a decreasing rate, from 1.5 kg palm⁻¹ year⁻¹ at 12 months old to 285.5 kg palm⁻¹ year⁻¹ after 133 months, with little increase thereafter. The maximum rates of nutrient demand occurred after 209 months, coinciding with peak production of fruit bunches—except for K, which occurred at month 88 when vegetative growth demand for K peaked. Annual gross amounts of nutrients required to produce 25 t fresh fruit bunches ha⁻¹ were 1.99 kg N, 0.28 kg P, 3.94 kg K, 0.42 kg Mg, 0.99 kg Ca, and 2.5 g B per palm. The net amounts of nutrients required to meet similar production level of fruit bunches were 1.04 kg N, 0.16 kg P, 1.85 kg K, 0.26 kg Mg, 0.47 kg Ca, and 1.3 g B per palm per year if all nutrients contained in the pruned leaves were recycled. These results provide much-needed updated data on the dry-matter production and nutrient demand of tenera oil palm grown under current agronomic practices and also serve as a general yardstick for practitioners to further refine fertilizer recommendations. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2418 KiB

Open AccessArticle

Is the Two-Line Hybrid Rice a Hindrance to the Efficient Use of Nitrogen Fertilizer in China?

by Zhiyuan Yang, Qingyue Cheng, Ruining Lai, Yuemei Zhu, Jinyue Zhang, Chuanhai Shu, Feijie Li, Tengfei Lv, Yongjian Sun, Jun Ma and Na Li

Agriculture 2022, 12(2), 250; https://doi.org/10.3390/agriculture12020250 - 09 Feb 2022

Viewed by 1839

Abstract

Two-line hybrid rice (2LH) is accompanied by more nitrogen (N) input. To explore the difference in response of two-line and three-line hybrid rice (3LH) to N application, a three-year split-plot experiment was conducted. Three 2LHs and three 3LHs were set as main plots, [...] Read more.

Two-line hybrid rice (2LH) is accompanied by more nitrogen (N) input. To explore the difference in response of two-line and three-line hybrid rice (3LH) to N application, a three-year split-plot experiment was conducted. Three 2LHs and three 3LHs were set as main plots, and four N rates including 0 kg ha⁻¹ (N0), 90 kg ha⁻¹ (N90), 150 kg ha⁻¹ (N150), and 210 kg ha⁻¹ (N210) were set as subplots. 3LH had more panicles and yielded 7.95%, 6.31%, and 5.48% higher than 2LH in N0, N90, and N150, respectively. 2LH had a greater panicle weight in N210 and yielded 1.45% higher than 3LH. Leaf area index (LAI) had the greatest effect on the yields of both 2LH and 3LH, while the contribution of light extinction coefficient (K) was 46.35% and 12.80% those of LAI, respectively. The LAI, K, and radiation interception rate (RIR) of 2LH were smaller than those of 3LH in N0 and N90. The K of 2LH increased significantly as the N rate increased from 150 kg ha⁻¹ to 210 kg ha⁻¹, while that of 3LH showed no significant change, making the maximum RIR of 2LH greater than that of 3LH. 2LH, which intercepted more radiation through greater leaf extension to achieve higher yields, was able to use nitrogen fertilizer efficiently under a high N rate in China. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 3275 KiB

Open AccessArticle

Evaluation of Agrobiodiversity and Cover Crop Adoption in Southern Ontario Field Crops

by Katherine Shirriff, Krishna Bahadur KC and Aaron Berg

Agronomy 2022, 12(2), 415; https://doi.org/10.3390/agronomy12020415 - 07 Feb 2022

Cited by 1 | Viewed by 1904

Abstract

Incorporating cover crops into corn and soybean operations across Southern Ontario is essential for maintaining yields under environmental stressors. Unfortunately, amongst the literature, there is a concern about the low adoption rate of cover crops in the northern Corn Belt due to a [...] Read more.

Incorporating cover crops into corn and soybean operations across Southern Ontario is essential for maintaining yields under environmental stressors. Unfortunately, amongst the literature, there is a concern about the low adoption rate of cover crops in the northern Corn Belt due to a shift toward low agrobiodiversity and dominance of more profitable corn and soybean cropping systems, encouraged by extensive use of fertilizers, herbicides, and pesticides. This study examines whether Southern Ontario is following suit in decreasing agrobiodiversity trends, at the county level, and examines the adoption of cover crops within corn and soybean operations across Southern Ontario using digital imagery from 2013 to 2018. Results reveal that Southern Ontario is indeed shifting from systems characterized by higher agrobiodiversity to systems dominated with corn, soybean, and hay. Despite the benefits of cover crops, this study reveals that most of the current corn and soybean operations are not incorporating cover crops into the rotation. More significantly, the low adoption of cover crops is most apparent in southwestern Ontario, and increases in adoption occur toward the north. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 300 KiB

Open AccessArticle

Chemical Properties of Soil and Cassava Yield as a Function of Weed Management by Cover Crops in the Amazon Ecosystem

by Daniel Oscar Soares, Karla Gabrielle Pinto, Prasanta Chitta Bhowmik and Sônia Maria Albertino

Sustainability 2022, 14(3), 1886; https://doi.org/10.3390/su14031886 - 07 Feb 2022

Cited by 1 | Viewed by 1859

Abstract

Cassava (Manihot esculenta) yields are severely affected by the interference of weed plants. Using cover crops for weed control appears as a sustainable alternative practice because it maintains the soil covered and reduces the need for herbicides. The aim of this [...] Read more.

Cassava (Manihot esculenta) yields are severely affected by the interference of weed plants. Using cover crops for weed control appears as a sustainable alternative practice because it maintains the soil covered and reduces the need for herbicides. The aim of this study was to assess cassava crop yields and the soil chemical properties as a function of use of cover crops for weed management. Treatments were three cover crops (Brachiaria ruziziensis, Canavalia ensiformis, and Mucuna pruriens), chemical control, mechanical control, and treatment with no weed control. Cover crops reduced the diversity of species and the quantity of individuals of the weed community in cassava cultivation. The treatments with chemical and physical weed control achieved higher yields. The cover crops B. ruziziensis and C. ensiformis increased cassava yields by 30% and 14%, respectively, when compared with the treatment with no control. The cover crops increased the pH, MO, K, Ca, and Mg values when compared with the treatments with chemical and mechanical weed control. Brachiaria ruziziensis and C. ensiformis are recommended as a cover plants in cassava production systems in the Amazon region. The use of cover crops associated with cassava is a sustainable management option because, in addition to the suppressive effect on weeds, cover crops improve the chemical properties of soil, which may contribute to increasing cassava production in the long term. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

14 pages, 3241 KiB

Open AccessEditor’s ChoiceArticle

Effect of Straw Length, Stubble Height and Rotary Speed on Residue Incorporation by Rotary Tillage in Intensive Rice–Wheat Rotation System

by Gaoming Xu, Yixuan Xie, Md. A. Matin, Ruiyin He and Qishuo Ding

Agriculture 2022, 12(2), 222; https://doi.org/10.3390/agriculture12020222 - 03 Feb 2022

Cited by 12 | Viewed by 2598

Abstract

High-yielding agriculture in an intensive rice–wheat rotation system leads to plenty of residues left in the field after harvest, which is detrimental to seeding operation, seed germination, and early plant growth. Some residue thus needs to be incorporated into the soil. Providing the [...] Read more.

High-yielding agriculture in an intensive rice–wheat rotation system leads to plenty of residues left in the field after harvest, which is detrimental to seeding operation, seed germination, and early plant growth. Some residue thus needs to be incorporated into the soil. Providing the relationship between tillage operations and residue incorporation and establishing a mathematical model play important roles in residue management and the design of tillage machinery. In order to obtain detailed data on the interaction between residue incorporation and tillage operations, a multifunctional field-testing bench with precise parameter control was developed to assess residue incorporation characteristics of rotary tillage, and we investigated the effects of straw length, stubble height and rotary speed on residue incorporation. Three experimental factors affecting residue incorporation performance were studied, i.e., six lengths of straw (30–150 mm), four heights of stubble (50–200 mm), and three rotary speeds (240–320 rpm). Chopped straw and stubble with certain sizes were prepared for the test, and we measured the burying rate and distribution uniformity of residue after rotary tillage. The results indicated that straw length, stubble height, and rotary speed all impact residue incorporation quality. The burying rate and distribution uniformity of residue decreased with the increase in straw length and stubble height; a lower rotary speed parameter buried less residue and distributed it with worse uniformity than a higher one. It is suggested that farmers determine the straw length and stubble height at the stage of harvest according to the required burying rate and distribution uniformity of residue. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2393 KiB

Open AccessArticle

Nitrogen Fertilization Weakly Influences the Anatomy and Chemical Composition of Rice Leaves

by Miao Ye, Zhengcan Zhang, Guanjun Huang and Zujian Zhang

Agriculture 2022, 12(2), 215; https://doi.org/10.3390/agriculture12020215 - 01 Feb 2022

Cited by 1 | Viewed by 1671

Abstract

In this paper, four rice genotypes showing different leaf mass per area (LMA) are used to explore the effects of nitrogen (N) supplies on rice leaf anatomy and leaf chemical composition as well as their impacts on leaf gas exchange parameters. The results [...] Read more.

In this paper, four rice genotypes showing different leaf mass per area (LMA) are used to explore the effects of nitrogen (N) supplies on rice leaf anatomy and leaf chemical composition as well as their impacts on leaf gas exchange parameters. The results showed that the mass-based and area-based leaf N contents as well as the net photosynthetic rate (A) under high N supply (HN) were all higher than those under a low N supply (LN). However, N supplies had no effect on stomatal conductance, mesophyll conductance, and photosynthetic N use efficiency. Moreover, N supplies had no significant effect on LMA and cell wall thickness. Leaf thickness and leaf density responses to N supplies were inconsistent in different genotypes. Except for the soluble sugar in Huanghuazhan and non-structural carbohydrates (NSC) in Sab Ini, N supplies showed no significant effects on mass-based leaf chemical components (pectic substance, hemicellulose, cellulose, lignin, total cell wall, soluble sugar, starch and NSC) content. The area-based leaf chemical components content showed significant differences between HN and LN in some occasions. The soluble sugar, NSC, hemicellulose, and lignin contents of Sab Ini under HN were higher than those under LN. The pectic substance, hemicellulose, and lignin contents of Huanghuazhan under LN were higher than those under HN. The cellulose and cell wall contents of Yongyou 12 under LN were higher than those under HN. Therefore, we conclude that nitrogen fertilization weakly influences the anatomy and chemical composition of rice leaves with a few exceptions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2853 KiB

Open AccessArticle

Digital Mapping of Soil Profile Properties for Precision Agriculture in Developing Countries

by Antonio López-Castañeda, Joel Zavala-Cruz, David Jesús Palma-López, Joaquín Alberto Rincón-Ramírez and Francisco Bautista

Agronomy 2022, 12(2), 353; https://doi.org/10.3390/agronomy12020353 - 31 Jan 2022

Cited by 4 | Viewed by 3828

Abstract

The soil profile and its spatial distribution are two essential aspects for promoting sustainable agriculture, with precise inputs in quantity, space, and time. This work’s objective was to elaborate a digital map of soil fertility considering the complete profile for the accurate management [...] Read more.

The soil profile and its spatial distribution are two essential aspects for promoting sustainable agriculture, with precise inputs in quantity, space, and time. This work’s objective was to elaborate a digital map of soil fertility considering the complete profile for the accurate management of amendments and fertilizers. For the preparation of the soil fertility map, the following inputs were used: a digital elevation model, information from 44 soil profiles, the conversion of the properties of the soil profiles into surface units, geostatistical analysis of the soil properties, and the preparation of the final map with a geographic information system. The best spatial models were achieved with CEC, pH, Ca, Mg, Na, and K. The map of the soil fertility classes was produced considering CEC and the pH value. The soil fertility classes presented the following sequence of occupied surfaces: very low, medium, very high, high, and low. A process was generated to elaborate digital maps (geostatistics) of soil fertility using taxonomic information from soil profiles and considering the complete profile. The process converts soil classification into geographic and soil fertility information from basic science to application. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2774 KiB

Open AccessArticle

Studies on the Possibilities of Processing Buckwheat Husks and Ash in the Production of Environmentally Friendly Fertilizers

by Odeta Pocienė and Rasa Šlinkšienė

Agriculture 2022, 12(2), 193; https://doi.org/10.3390/agriculture12020193 - 30 Jan 2022

Cited by 2 | Viewed by 2905

Abstract

The sustainable utilization of different food waste and other products is one of the challenges of the European Green Course. Buckwheat has major potential as a food ingredient; however, processing buckwheat into food products generates a large amount of solid waste that needs [...] Read more.

The sustainable utilization of different food waste and other products is one of the challenges of the European Green Course. Buckwheat has major potential as a food ingredient; however, processing buckwheat into food products generates a large amount of solid waste that needs to be sustainably disposed of. The by-products that come from the processing of the buckwheat contain high contents of carbon and hydrogen and can be used as raw materials for the production of granular biofuels. This work proposes and explores the potential of a different route of buckwheat husk ash utilization. Chemical analysis of the buckwheat husk ash (BHA) and uncleaned buckwheat husks (UBH) showed significant amounts of primary and secondary nutrients (0.28 ± 0.06%–5.84 ± 0.43% P₂O₅; 4.56 ± 0.46%–38.63 ± 1.82% K₂O; 0.09 ± 0.01%–12.18 ± 0.38% CaO and 0.47 ± 0.08%–3.56 ± 0.18% MgO) as well as micronutrients (Zn, Mn, Cu, and Fe) and carbon (29.53 ± 0.50%–54.35 ± 0.58% C). It has been determined that granular biofertilizers can be produced by using drum granulators from the mixture of raw materials in an 80–20% BHA, 20–80% UBH, and 10% polyvinyl acetate (PVA) solution. However, when more than 20% of the UBH is present in the raw material mixture, the humidity of granules is high (more than 6%), and bulk density is low (less than 450 kg/m³). The pH values of 10% solution of the produced granules range from 12.0 to 9.7; thus, the fertilizers can act as a liming agent, which can be recommended for acid soils. This suggests a potential for a cradle-to-cradle type of regenerative engineering process design, where the end product of buckwheat processing—buckwheat husk ash and untreated buckwheat husks—can be returned back to the soil to replenish the nutrients, resulting in an overall sustainable process. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 2725 KiB

Open AccessArticle

Matching of Nitrogen Enhancement and Photosynthetic Efficiency by Arbuscular Mycorrhiza in Maize (Zea mays L.) in Relation to Organic Fertilizer Type

by Suravoot Yooyongwech, Waraporn Threeprom, Rujira Tisarum, Thapanee Samphumphuang, Daonapa Chungloo and Suriyan Cha-um

Plants 2022, 11(3), 369; https://doi.org/10.3390/plants11030369 - 29 Jan 2022

Cited by 5 | Viewed by 2788

Abstract

In the present study, Funneliformis mosseae (FM), Claroideoglomus etunicatum (CE), and Acaulospora foveata (AF) were inoculated to hybrid maize (Zea mays L. cv. CP888^®). Upregulation of nitrogen levels were dependent on the type of mycorrhiza (AMF). Photosynthetic efficiency (F_v [...] Read more.

In the present study, Funneliformis mosseae (FM), Claroideoglomus etunicatum (CE), and Acaulospora foveata (AF) were inoculated to hybrid maize (Zea mays L. cv. CP888^®). Upregulation of nitrogen levels were dependent on the type of mycorrhiza (AMF). Photosynthetic efficiency (F_v/F_m) and water content in FM- and AF-inoculated plants were elevated, resulting in promotion of leaf area and shoot biomass. N content in the shoot and root tissues of the FM-inoculated plants increased by 21% and 30% over the control. A positive correlation between biochemical, physiological, and morphological parameters using Pearson’s coefficient was demonstrated. A decline in lipid peroxidation was noticed in the FM-inoculated plants. In addition, we investigated the potential of N fertilizer application in combination with FM inoculation in maize plants. The FM-inoculated plants with organic O_LT, a chicken manure fertilizer, increased N content in the host shoots by 73% over the control, leading to improved F_v/F_m as a physiological adaptation strategy. The FM and the O_LT on the regulation of the N enhancement and photosynthetic efficiency of the hybrid maize should further be validated in field trials in different environments for sustainability. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 4201 KiB

Open AccessArticle

Effect of Seaweed Extract Supplement on Rice Rhizosphere Bacterial Community in Tillering and Heading Stages

by Chun-Lin Chen, Wan-Lin Song, Lin Sun, Song Qin, Cheng-Gang Ren, Jian-Chao Yang, Da-Wei Feng, Ning Liu, Jun Yan, Bi-Bo Cui, Zhi-Hai Zhong, Qing-Quan Li, Zhi-Dan Liu and Zheng-Yi Liu

Agronomy 2022, 12(2), 342; https://doi.org/10.3390/agronomy12020342 - 29 Jan 2022

Cited by 7 | Viewed by 4326

Abstract

Rhizosphere microbiota are conducive to soil nutrient cycling for plant growth. Long-term and excessive application of chemical fertilizer is harmful to agriculture. Seaweed extract is a good organic substitute for rhizosphere ecosystem and plant growth. We supplemented 5‰ seaweed extract powder to chemical [...] Read more.

Rhizosphere microbiota are conducive to soil nutrient cycling for plant growth. Long-term and excessive application of chemical fertilizer is harmful to agriculture. Seaweed extract is a good organic substitute for rhizosphere ecosystem and plant growth. We supplemented 5‰ seaweed extract powder to chemical fertilizer, and then studied its effect on rhizosphere bacteria of japonica rice (Oryza sativa L. subsp. japonica). In a short-term experiment, we compared the changes in rhizosphere bacteria among four treatments, i.e., no fertilizer (T1), chemical fertilizer only (T2), chemical fertilizer with 5‰ seaweed extract (T3), and less chemical fertilizer with 5‰ seaweed extract (80% of that of T3) (T4). Results show that seaweed extract supplement could affect the bacterial community in tillering and heading stages; the α-diversity of rhizosphere bacteria in the heading stage was obviously improved. In addition, seaweed extract supplement improved significantly the content of nitrate nitrogen (N), available phosphorus (P), and available potassium (K) in rhizosphere soil in the tillering stage, and, finally, increased the rice yield and quality mildly. Therefore, the seaweed extract supplement is shown to be a potential strategy to enrich the diversity of rhizosphere bacteria, which enhanced soil nutrient level, increased rice yield and quality, and also saved the use of chemical fertilizer. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 4363 KiB

Open AccessArticle

Short-Term Effects of Reclamation of Aquaculture Ponds to Paddy Fields on Soil Chemical Properties and Bacterial Communities in Eastern China Coastal Zone

by Anyong Hu, Min Lv, Shumiao Jiang, Lingyi Xu, Shiyang Guo, Na Zhao, Manman Zheng, Bo Liu and Jinbiao Li

Sustainability 2022, 14(3), 1613; https://doi.org/10.3390/su14031613 - 29 Jan 2022

Cited by 1 | Viewed by 2693

Abstract

Large areas of tidal flats were previously developed into aquaculture ponds and were recently encouraged to be converted into paddy fields to fulfill food and economic needs in China. However, the influences of short-term rice cultivation at the reclaimed aquaculture ponds on soil [...] Read more.

Large areas of tidal flats were previously developed into aquaculture ponds and were recently encouraged to be converted into paddy fields to fulfill food and economic needs in China. However, the influences of short-term rice cultivation at the reclaimed aquaculture ponds on soil chemical properties and bacterial communities are poorly understood. To address this issue, we collected mineral soil samples at 0–20 and 20–40 cm depths from non-cultivated soils and paddy fields after being reclaimed from aquaculture ponds in Nantong, China, and identified soil bacterial communities using high-throughput sequencing. The results suggested that rice cultivation significantly increased the accumulation of total soil carbon (TC) and dissolved organic carbon (WSOC). The pH, ammonium (NH₄⁺), nitrate (NO₃⁻) and available phosphorus (AP) varied with the reclamation duration but did not show a unanimous tendency. Proteobacteria, Acidobacteria, Bacteroidetes, Chloroflexi and Planctomycetes dominated the bacterial community in both non-cultivated and cultivated soils after reclamation regardless of cultivation ages and soil depth. The variations in the diversity and composition of the soil microbial community were mainly associated with electrical conductivity (EC), WSOC, TC, NH₄⁺ and NO₃⁻ in non-cultivated and cultivated lands. Here, we found that short-term rice cultivation at the reclaimed aquaculture ponds strongly influenced soil bacterial communities and chemical properties, especially in the 0–20 cm depth, in the coastal regions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 2361 KiB

Open AccessEditor’s ChoiceArticle

Esmeralda Peach (Prunus persica) Fruit Yield and Quality Response to Nitrogen Fertilization

by Gilberto Nava, Carlos Reisser Júnior, Léon-Étienne Parent, Gustavo Brunetto, Jean Michel Moura-Bueno, Renan Navroski, Jorge Atílio Benati and Caroline Farias Barreto

Plants 2022, 11(3), 352; https://doi.org/10.3390/plants11030352 - 27 Jan 2022

Cited by 7 | Viewed by 3176

Abstract

‘Esmeralda’ is an orange fleshed peach cultivar primarily used for juice extraction and secondarily used for the fresh fruit market. Fruit yield and quality depend on several local environmental and managerial factors, mainly on nitrogen, which must be balanced with other nutrients. Similar [...] Read more.

‘Esmeralda’ is an orange fleshed peach cultivar primarily used for juice extraction and secondarily used for the fresh fruit market. Fruit yield and quality depend on several local environmental and managerial factors, mainly on nitrogen, which must be balanced with other nutrients. Similar to other perennial crops, peach trees show carryover effects of carbohydrates and nutrients and of nutrients stored in their tissues. The aims of the present study are (i) to identify the major sources of seasonal variability in fruit yield and qu Fruit Tree Department of Federal University of Pelotas (UFPEL), Pelotas 96010610ality; and (ii) to establish the N dose and the internal nutrient balance to reach high fruit yield and quality. The experiment was conducted from 2014 to 2017 in Southern Brazil and it followed five N treatments (0, 40, 80, 120 and 160 kg N ha⁻¹ year⁻¹). Foliar compositions were centered log-ratio (clr) transformed in order to account for multiple nutrient interactions and allow computing distances between compositions. Based on the feature ranking, chilling hours, degree-days and rainfall were the most influential features. Machine learning models k-nearest neighbors (KNN) and stochastic gradient decent (SGD) performed well on yield and quality indices, and reached accuracy from 0.75 to 1.00. In 2014, fruit production did not respond to added N, and it indicated the carryover effects of previously stored carbohydrates and nutrients. The plant had a quadratic response (p < 0.05) to N addition in 2015 and 2016, which reached maximum yield of 80 kg N ha⁻¹. In 2017, harvest was a failure due to the chilling hours (198 h) and the relatively small number of fruits per tree. Fruit yield and antioxidant content increased abruptly when foliar clr_Cu was >−5.410. The higher foliar P linearly decreased total titratable acidity and increased pulp firmness when clr_P > 0.556. Foliar N concentration range was narrow at high fruit yield and quality. The present results have emphasized the need of accounting for carryover effects, nutrient interactions and local factors in order to predict peach yield and nutrient dosage. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 3982 KiB

Open AccessArticle

Overwintering and Yield Responses of Two Late-Summer Seeded Alfalfa Cultivars to Phosphate Supply

by Yuntao Wang, Jiageng Zhang, Linqing Yu, Zhanyou Xu and Deborah A. Samac

Agronomy 2022, 12(2), 327; https://doi.org/10.3390/agronomy12020327 - 26 Jan 2022

Cited by 7 | Viewed by 2847

Abstract

Phosphorus (P) is one of the essential nutrients for alfalfa (Medicago sativa L.) growth, but P deficiency in soil is a common phenomenon. Applying an appropriate amount of P fertilizer for alfalfa in the establishment year improves winter survival, helps achieve sustainable [...] Read more.

Phosphorus (P) is one of the essential nutrients for alfalfa (Medicago sativa L.) growth, but P deficiency in soil is a common phenomenon. Applying an appropriate amount of P fertilizer for alfalfa in the establishment year improves winter survival, helps achieve sustainable high yields, and promotes the best economic returns. The objective of this study was to determine the effect of different P fertilization rates (0, 22, 44, and 66 kg P ha⁻¹) on winter survival, forage yield, and root traits of two late-summer seeded alfalfa cultivars (dormant and semi-dormant) in the establishment and first production year. Our results showed that applying an appropriate amount of P fertilizer can increase forage yield and enhance the persistence of late-summer seeded alfalfa by promoting the development of crown and root traits and improving winter survival, especially for semi-dormant cultivars. Late-summer seeding and application of appropriate P fertilizer rates are effective agronomic methods for alfalfa in cold and arid winter regions, and can be used as strategies to improve fertility and stabilize soil from wind erosion for sustainable agriculture. To obtain high rate of survival in winter, the optimal P fertilization rates for the dormant and semi-dormant alfalfa cultivars in this study were 31.4 and 41.3 kg P ha⁻¹, whereas the optimum P application rates for high forage yields were 31.3 and 31.5 kg P ha⁻¹, respectively. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 4568 KiB

Open AccessArticle

Long-Term Compost Amendment Changes Interactions and Specialization in the Soil Bacterial Community, Increasing the Presence of Beneficial N-Cycling Genes in the Soil

by Jessica Cuartero, Onurcan Özbolat, Virginia Sánchez-Navarro, Julia Weiss, Raúl Zornoza, José Antonio Pascual, Juana-María Vivo and Margarita Ros

Agronomy 2022, 12(2), 316; https://doi.org/10.3390/agronomy12020316 - 26 Jan 2022

Cited by 5 | Viewed by 3556

Abstract

Significant differences in the microbial community and diversity in soil have been observed due to organic farming, but little research has been performed for exploring microbial functionality and the co-occurrence of patterns among microbial taxa. In this work, we study soil 16S rDNA [...] Read more.

Significant differences in the microbial community and diversity in soil have been observed due to organic farming, but little research has been performed for exploring microbial functionality and the co-occurrence of patterns among microbial taxa. In this work, we study soil 16S rDNA amplicons from two long-term organic farming systems (Org_C and Org_M) and a conventional system (Conv) to decipher the differences in microbial interaction and network organization and to predict functional genes (principally related to the N cycle). In general, the network organizations were different in all cropping systems due to agricultural management. Org_C showed the highest negative interactions and modularity and the most altered bacterial niches and interactions, which led to an increase in generalist species that stabilize the bacterial community and improve the response of the soil to adverse conditions. These changes altered the predicted functionality of the bacterial community; Org_C showed higher referred numbers of nitrogen fixation genes, a decrease in the N₂O emission genes and could favor the uptake of environmental CO₂. Thus, long-term compost amendment application has significant benefits for the farmer and the environment, since prolonged application can reduce the use of fertilizers and pesticides and could create a more stable soil, which could resist the effects of climate change. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1843 KiB

Open AccessArticle

Photosynthesis, Yield, Nutrient Availability and Soil Properties after Biochar, Zeolites or Mycorrhizal Inoculum Application to a Mature Rainfed Olive Orchard

by João Ilídio Lopes, Margarida Arrobas, Soraia Raimundo, Alexandre Gonçalves, Cátia Brito, Sandra Martins, Luís Pinto, José Moutinho-Pereira, Carlos M. Correia and Manuel Ângelo Rodrigues

Agriculture 2022, 12(2), 171; https://doi.org/10.3390/agriculture12020171 - 25 Jan 2022

Cited by 10 | Viewed by 3254

Abstract

Soil conditioners and beneficial microorganisms are important tools that can be used to increase the sustainability of agro-systems. However, the high diversity of conditions where they can be applied may influence the results, which requires extensive field research. In this study, a field [...] Read more.

Soil conditioners and beneficial microorganisms are important tools that can be used to increase the sustainability of agro-systems. However, the high diversity of conditions where they can be applied may influence the results, which requires extensive field research. In this study, a field trial of four years was conducted in olive (Olea europaea L.) to assess the effect of biochar, zeolites and a commercial mycorrhizal inoculum in the photosynthetic performance, nutritional status of trees, olive yield and soil properties. The experimental design also included a fertilizer treatment with nitrogen (N), phosphorus (P), potassium (K) and boron (B), which nutrients were applied at 50 kg ha⁻¹ of N, P₂O₅ and K₂O and 2 kg ha⁻¹ of B, and an untreated control. The mineral fertilizer treatment increased significantly the dry mass of pruning wood and the average olive yield by 21% over the control treatment. The mineral treatment increased plant N nutritional status, the most likely reason why the trees of this treatment performed better. Overall, the soil treatments had net photosynthetic rates similar to each other and higher than the control treatment, from the second year onwards. Biochar increased soil organic matter, as a result of the carbon (C) contained in the amendment itself, and probably by stimulating soil biological activity. Biochar and zeolites did not improve the productive performances of the tress, but increased the soil cation exchange capacity (CEC), which can benefit the system in the long-term. Mycorrhizal fungi did not show any benefit for soil or plants, which could mean that mycorrhization was not established, or their effect was not better than that of native microorganisms. In the conditions of this study, the interest of using commercial mycorrhizal fungi in a mature olive orchard seems to be low. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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23 pages, 3370 KiB

Open AccessArticle

Meat Processing Waste as a Source of Nutrients and Its Effect on the Physicochemical Properties of Soil

by Arkadiusz Stępień, Katarzyna Wojtkowiak, Małgorzata Grzywińska-Rąpca and Jan Pawluczuk

Sustainability 2022, 14(3), 1341; https://doi.org/10.3390/su14031341 - 25 Jan 2022

Cited by 3 | Viewed by 2062

Abstract

The aim of this study was to determine the effect of meat processing waste applied in the form of meat and bone meal (MBM) as a source of nutrients on the physicochemical properties of soil. A short–term small–area field experiment using MBM in [...] Read more.

The aim of this study was to determine the effect of meat processing waste applied in the form of meat and bone meal (MBM) as a source of nutrients on the physicochemical properties of soil. A short–term small–area field experiment using MBM in maize monoculture was conducted in 2014–2017. Each year, MBM was applied presowing at 1.0, 2.0, and 3.0 t ha⁻¹ to maize grown in experimental plots. The application of MBM decreased the bulk density and specific density and increased the pH of Haplic Luvisol Loamic (HLL) soil. The mineral nitrogen (N) content was highest when MBM was applied at 3.0 t ha⁻¹ in HLL soil and 2.0 t ha⁻¹ in Haplic Luvisol Arenic (HLA) soil. The minor differences in the mineral N content of soil between the treatment without fertilization and MBM treatments could be attributed to high N utilization by maize plants. The phosphorus (P) content of soil increased with a rise in the MBM dose. The P content of the arable layer was lower in HLA soil than in HLL soil, which resulted from higher P uptake by maize grain. The highest maize grain yield was achieved in the last year of the study, in response to the highest MBM dose and due to the residual effect of MBM. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 2229 KiB

Open AccessArticle

Substrate-Driven Phosphorus Bioavailability Dynamics of Novel Inorganic and Organic Fertilizing Products Recovered from Municipal Wastewater—Tests with Ryegrass

by Aleksandra Bogdan, Ana A. Robles-Aguilar, Qianxin Liang, Sabolc Pap, Evi Michels and Erik Meers

Agronomy 2022, 12(2), 292; https://doi.org/10.3390/agronomy12020292 - 24 Jan 2022

Cited by 8 | Viewed by 3124

Abstract

Municipal wastewater is a valuable source of phosphorus (P) for the production of fertilizing products, such as microalgae (MA), crab carapace material (CCM), P salt produced by chemical leaching of sludge (P salt CL), and sewage sludge ash produced by pyrolysis and the [...] Read more.

Municipal wastewater is a valuable source of phosphorus (P) for the production of fertilizing products, such as microalgae (MA), crab carapace material (CCM), P salt produced by chemical leaching of sludge (P salt CL), and sewage sludge ash produced by pyrolysis and the incineration of sludge (SSA PI). This study compares the P availability of these fertilizing products in three planting substrates (S1, S2, and S3) during a four-month growth period of perennial ryegrass. The unfertilized control in substrate S3 had a high and available P that masked the effect of the added fertilizing products. The P salt CL fertilizer exhibited the lowest shoot dry matter in the alkaline S2 substrate. Still, it can be used as a good source of P in both acidic and alkaline substrates, given that its shoot P content was among the highest in all substrates tested. The organic-rich fertilizing products, MA and CCM, are better suited for acidic substrates since a pronounced reduction in the shoot yield and P content was seen in the alkaline S2 substrate. In contrast, for the SSA PI fertilizer, the very small differences in shoot dry matter and P content in S1 compared to S2 indicated that it is suitable for both acidic and alkaline substrates. Four months were needed to observe the maximum shoot yields treated with these P fertilizing products. Considering that the substrate solution P (using Rhizons) for the P salt CL and MA fertilizers proved to be similar to shoot P uptake, Rhizon extraction could be used for assessing P bioavailability. The chemical composition of novel products indicated their potential to deliver not only P, but also other nutrients to plants. However, concentrations of inorganic contaminants in all products, except CCM, pointed out a possibility to pollute the environment by applying these fertilizers. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 2264 KiB

Open AccessArticle

Grazing and Mowing Affect the Carbon-to-Nitrogen Ratio of Plants by Changing the Soil Available Nitrogen Content and Soil Moisture on the Meadow Steppe, China

by Le Wang, Hengkang Xu, Hao Zhang and Yingjun Zhang

Plants 2022, 11(3), 286; https://doi.org/10.3390/plants11030286 - 21 Jan 2022

Cited by 11 | Viewed by 2928

Abstract

Common grassland management practices affect plant and soil element stoichiometry, but the primary environmental factors driving variation in plant C/N ratios for different species in different types of grassland management remain poorly understood. We examined the three dominant C/N stoichiometric responses of plants [...] Read more.

Common grassland management practices affect plant and soil element stoichiometry, but the primary environmental factors driving variation in plant C/N ratios for different species in different types of grassland management remain poorly understood. We examined the three dominant C/N stoichiometric responses of plants to different land uses (moderate grazing and mowing) in the temperate meadow steppe of northern China. Our results showed that the responses of the C/N ratio of dominant plants differed according to the management practice. The relative abundance of N in plant tissues increased due to increased soil NO₃⁻, with a consequent decrease in plant C: N in the shoots of Leymus chinensis, but the C/N ratio and nitrogen concentration in the shoots of Bromus inermis and Potentilla bifurca were relatively stable under short-term moderate grazing management. Mowing reduced the concentration of soil NH₄⁺, thus reducing the nitrogen concentration of the roots, resulting in a decrease in the root C/N ratio of Potentilla bifurca. Structural equation model (SEM) showed that the root C/N ratio was affected by both root N and soil inorganic N, while shoot C/N ratio was only affected by the soil inorganic N. Our findings provide a mechanistic understanding of the responses of plant C/N ratio to land use change. The species-level responses of plant stoichiometry to human-managed grasslands deserve more attention. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 4071 KiB

Open AccessArticle

Leaf and Fruit Nutrient Concentration in Rojo Brillante Persimmon Grown under Conventional and Organic Management, and Its Correlation with Fruit Quality Parameters

by Nariane Q. Vilhena, Ana Quiñones, Isabel Rodríguez, Rebeca Gil, Paula Fernández-Serrano and Alejandra Salvador

Agronomy 2022, 12(2), 237; https://doi.org/10.3390/agronomy12020237 - 18 Jan 2022

Cited by 7 | Viewed by 2265

Abstract

This study aimed to evaluate the concentrations of the main macroelements in leaves and fruit grown following organic and conventional practices, and to relate them to physico-chemical parameters during commercial fruit harvests. Three samplings were carried out during fruit maturation. Nitrogen (N), phosphorus [...] Read more.

This study aimed to evaluate the concentrations of the main macroelements in leaves and fruit grown following organic and conventional practices, and to relate them to physico-chemical parameters during commercial fruit harvests. Three samplings were carried out during fruit maturation. Nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) were determined in leaves and in two fruit flesh areas: basal and apical. Weight, color, firmness, soluble tannins (ST), and total soluble solids (TSS) were also evaluated in fruit. During the study period, the lowering leaf N concentration was accompanied by its increment in flesh. Leaf P and K lowered but did not imply changes in these concentrations in fruit. N, P, and K concentrations were higher in the apical area than in the basal flesh. No changes in Ca concentration occurred in leaf, but Ca translocation from the basal to the apical area was detected in fruit. Management affected the concentrations of leaf K and Mg and the fruit N, P and Ca. The agronomic efficiency of the macronutrients in the organic crops was superior to that in the conventional crops. The Ca and Mg and the N/Ca and Ca/(K+Mg) ratios were closely related to color, firmness, TSS, and ST content. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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28 pages, 5342 KiB

Open AccessArticle

Maximizing Leaves, Inflorescences, and Chemical Composition Production of Moringa oleifera Trees under Calcareous Soil Conditions

by Amira K. G. Atteya, Aishah N. Albalawi, Hala M. Bayomy, Eman S. Alamri and Esmail A. E. Genaidy

Plants 2022, 11(2), 234; https://doi.org/10.3390/plants11020234 - 17 Jan 2022

Cited by 5 | Viewed by 2470

Abstract

One of the main issues limiting plant productivity is a lack of soil nutrient resources, especially in calcareous soil, which covers more than one third of the world’s land surface area. On the other hand, despite rising demand for all parts of the [...] Read more.

One of the main issues limiting plant productivity is a lack of soil nutrient resources, especially in calcareous soil, which covers more than one third of the world’s land surface area. On the other hand, despite rising demand for all parts of the Moringa oleifera tree, several studies have focused on its leaf production as an herbaceous plant, rather than as a tree, and no extensive research has been carried out on leaf and inflorescence production in the mature tree. As a result, the influence of vermicompost and NPK (minerals and nanoparticles), as well as their combination, under calcareous soil conditions, was investigated in this study. The experiment was set up as a split plot in Randomized Complete Block Design (RCBD) with three replicates. In both seasons considered in this study, it was discovered that increasing the quantity of vermicompost and employing NPK fertilization, as well as their combination treatments, greatly enhanced all parameters and yield of distinct Moringa oleifera tree parts. Furthermore, the combination treatment T21 yielded the highest mean values of growth, leaves, and chemical composition parameters, as well as the highest yield from the Moringa oleifera tree. In both seasons, the highest number of inflorescences per tree, as well as the yield of fresh and dry inflorescences, was measured using combination treatment T18. In both seasons, however, increasing the level of vermicompost, NPK, and their combination treatments significantly reduced the total phenolic and flavonoid content and antioxidant activity of dry Moringa oleifera leaves. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2071 KiB

Open AccessArticle

16S rRNA Gene-Based Metagenomic Analysis of Rhizosphere Soil Bacteria in Arkansas Rice Crop Fields

by Cássia Oliveira, Ehsan Shakiba, Dustin North, Madison McGraw, Ethan Ballard, Marissa Barrett-D’Amico, Galina Glazko and Yasir Rahmatallah

Agronomy 2022, 12(1), 222; https://doi.org/10.3390/agronomy12010222 - 17 Jan 2022

Cited by 11 | Viewed by 4309

Abstract

The rhizomicrobiome is composed of microbes that live in association with plant roots. From nutrient cycling to carbon sequestration, soil microorganisms have provided a solid base for natural and agricultural ecosystems to function. The relationship between plant roots and soil microorganisms is especially [...] Read more.

The rhizomicrobiome is composed of microbes that live in association with plant roots. From nutrient cycling to carbon sequestration, soil microorganisms have provided a solid base for natural and agricultural ecosystems to function. The relationship between plant roots and soil microorganisms is especially relevant in food staples such as rice (Oryza sativa L.), as the various properties of these microbes can influence crop yield and plant health, thereby affecting a major portion of the food supply for an ever-growing world population. In this study, we used 16S rRNA gene-based metagenomic analysis to investigate the impact of crop rotation and soil cultivation methods (no-till or tillage) on rhizosphere bacterial diversity and composition in eight crop fields in Arkansas. Illumina MiSeq sequencing revealed 56 Phyla, with four major Phyla: Proteobacteria, Acidobacteria, Actinobacteria, and Bacteroidetes. Soil microbial communities in the samples studied were phylogenetically diverse but with a stable community structure. Crop rotation and tillage did not significantly affect bacterial diversity. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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24 pages, 2257 KiB

Open AccessEditor’s ChoiceArticle

Soil Nutrient Retention and pH Buffering Capacity Are Enhanced by Calciprill and Sodium Silicate

by Ji Feng Ng, Osumanu Haruna Ahmed, Mohamadu Boyie Jalloh, Latifah Omar, Yee Min Kwan, Adiza Alhassan Musah and Ken Heong Poong

Agronomy 2022, 12(1), 219; https://doi.org/10.3390/agronomy12010219 - 17 Jan 2022

Cited by 30 | Viewed by 5101

Abstract

In the tropics, warm temperatures and high rainfall contribute to acidic soil formation because of the significant leaching of base cations (K⁺, Ca²⁺, Mg²⁺, and Na⁺), followed by the replacement of the base cations with [...] Read more.

In the tropics, warm temperatures and high rainfall contribute to acidic soil formation because of the significant leaching of base cations (K⁺, Ca²⁺, Mg²⁺, and Na⁺), followed by the replacement of the base cations with Al³⁺, Fe²⁺, and H⁺ ions at the soil adsorption sites. The pH buffering capacity of highly weathered acid soils is generally low because of their low pH which negatively impacts soil and crop productivity. Thus, there is a need to amend these soils with the right amount of inorganic liming materials which have relatively high neutralizing values and reactivity to overcome the aforementioned problems. Soil leaching and the pH buffering capacity studies were conducted to determine whether the co-application or co-amendment of a calcium carbonate product (Calciprill) and sodium silicate can improve soil nutrient retention and pH buffering capacity of the Bekenu series (Typic Paleudults). A 30 day soil leaching experiment was carried out using a completely randomized design with 16 treatments and 3 replications after which the leached soil samples were used for a pH buffering capacity study. The Calciprill and sodium silicate treatments significantly improved soil pH, exchangeable NH₄⁺, available P, exchangeable base cations, Effective Cation Exchange Capacity (ECEC), and pH buffering capacity in comparison with the untreated soil. The improvements were attributed to the alkalinity of Calciprill and sodium silicate due to their high inherent K⁺, Ca²⁺, Mg²⁺, and Na⁺ contents. The neutralizing effects of the amendments impeded the hydrolysis of Al³⁺ (96.5%), Fe²⁺ (70.4%), and Mn²⁺ (25.3%) ions resulting in fewer H⁺ ions being produced. The co-application of Calciprill and sodium silicate reduced the leaching of Ca²⁺ (58.7%) and NO₃⁻ (74.8%) from the amended soils. This was due to the ability of sodium silicate to reduce soil permeability and protect the Calciprill and available NO₃⁻ from being leached. This also improved the longevity of Calciprill to enhance the soil pH buffering capacity. However, the amounts of NH₄⁺, P, and base cations leached from the amended soils were higher compared with the un-amended soils. This was due to the high solubility of sodium silicate. The most suitable combination amendment was 7.01 g Calciprill and 9.26 g sodium silicate (C2S5) per kilogram soil. It is possible for farmers to adopt the combined use Calciprill and sodium silicate to regulate soil nutrient retention and improve the soil pH buffering capacity of highly weathered acidic soils. This will enhance soil and crop productivity. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 9423 KiB

Open AccessArticle

Application of Corn Straw and Woody Peat to Improve the Absorption and Utilization of ¹⁵N-Urea by Maize

by Chenming Lin, Sen Dou, Mahmoud Gamal Mohamed Abd El-Rahim, Xin Liu, Dong Wu, Rui Ma, Yifeng Zhang, Xianbao Yin, Cen Tan and Shuai Xie

Sustainability 2022, 14(2), 820; https://doi.org/10.3390/su14020820 - 12 Jan 2022

Cited by 3 | Viewed by 1870

Abstract

Increasing nitrogen fertilizer use efficiency has become an environmental and economic demand in order to minimize losses of nitrogen and maximize the output from nitrogen added. The application of organic amendments with N fertilizers could be proposed as an important economic and environmental [...] Read more.

Increasing nitrogen fertilizer use efficiency has become an environmental and economic demand in order to minimize losses of nitrogen and maximize the output from nitrogen added. The application of organic amendments with N fertilizers could be proposed as an important economic and environmental practice for improving N fertilizer use. A two-year field experiment was carried out using the ¹⁵N tracer technique to study the impact of corn straw and woody peat application on uptake and utilization of N fertilizer by maize plant. Three treatments were set up: CK (¹⁵N labeled urea alone), CS (¹⁵N labeled urea + crushed corn straw) and WP (¹⁵N labeled urea+ crushed woody peat). The results showed that, as compared to CK, both straw and peat treatments led to (i) an increase in yield of maize, ¹⁵N urea utilization rate, and residual ¹⁵N urea remained in soil by 11.20% and 19.47%, 18.62% and 58.99%, 41.77% and 59.45%, respectively, but (ii) a decrease in the total loss rate by 6.21% and 16.83% (p < 0.05), respectively over the two seasons. Moreover, the significantly highest effect was recorded with woody peat application rather than that with corn straw. Our study suggests that corn straw and woody peat can be used as organic fertilizers to increase maize yields, promote nitrogen fertilizer balance sheet, reduce the leaching of N fertilizer into the subsurface soil layer, and facilitate the further absorption and utilization of soil residual nitrogen. Therefore, the application of humified organic material play a crucial role in N utilization efficiency enhancement. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 4937 KiB

Open AccessArticle

Validation of Rapid and Low-Cost Approach for the Delineation of Zone Management Based on Machine Learning Algorithms

by Michele Denora, Marco Fiorentini, Stefano Zenobi, Paola A. Deligios, Roberto Orsini, Luigi Ledda and Michele Perniola

Agronomy 2022, 12(1), 183; https://doi.org/10.3390/agronomy12010183 - 12 Jan 2022

Cited by 10 | Viewed by 2711

Abstract

Proximal soil sensors are receiving strong attention from several disciplinary fields, and this has led to a rise in their availability in the market in the last two decades. The aim of this work was to validate agronomically a zone management delineation procedure [...] Read more.

Proximal soil sensors are receiving strong attention from several disciplinary fields, and this has led to a rise in their availability in the market in the last two decades. The aim of this work was to validate agronomically a zone management delineation procedure from electromagnetic induction (EMI) maps applied to two different rainfed durum wheat fields. The k-means algorithm was applied based on the gap statistic index for the identification of the optimal number of management zones and their positions. Traditional statistical analysis was performed to detect significant differences in soil characteristics and crop response of each management zones. The procedure showed the presence of two management zones at both two sites under analysis, and it was agronomically validated by the significant difference in soil texture (+24.17%), bulk density (+6.46%), organic matter (+39.29%), organic carbon (+39.4%), total carbonates (+25.34%), total nitrogen (+30.14%), protein (+1.50%) and yield data (+1.07 t ha⁻¹). Moreover, six unmanned aerial vehicle (UAV) flight missions were performed to investigate the relationship between five vegetation indexes and the EMI maps. The results suggest performing the multispectral images acquisition during the flowering phenological stages to attribute the crop spatial variability to different soil proprieties. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2141 KiB

Open AccessArticle

Evaluating the Fertilising Potential of Blended Recovered Nutrients in Horticultural Growing Medium on Viola x wittrockiana L.

by Ana A. Robles-Aguilar, Oliver Grunert, Erik Meers and Nicolai D. Jablonowski

Agronomy 2022, 12(1), 182; https://doi.org/10.3390/agronomy12010182 - 12 Jan 2022

Cited by 2 | Viewed by 1767

Abstract

Viola x wittrockiana L. is an ornamental plant in high demand in horticulture. It is becoming more critical for greenhouse growers to focus on sustainable production to enhance plant quality while reducing negative environmental impacts. Therefore, assessing the effect of recycled phosphorous (P) [...] Read more.

Viola x wittrockiana L. is an ornamental plant in high demand in horticulture. It is becoming more critical for greenhouse growers to focus on sustainable production to enhance plant quality while reducing negative environmental impacts. Therefore, assessing the effect of recycled phosphorous (P) and nitrogen (N) sources on the growth of viola could become very useful for producers in terms of sustainability. This experiment analysed the optimal fertiliser composition to grow viola using recovered fertilisers in a greenhouse trial under controlled conditions. Well-rooted viola plugs were grown in a standard peat-based growing medium. Using recycled sources of P and N as struvite and potassium struvite, ammonium sulphate, and ammonium nitrate, 14 fertiliser blends were prepared, tested, and compared with the slow-release commercial fertiliser Osmocote. Plants treated with ammonium nitrate showed healthy growth and optimal plant N concentrations. In contrast, most blends using the recovered ammonium sulphate resulted in an unacceptable increase of ammonium concentrations in the growing medium. The combination of ammonium sulphate and potassium sulphate caused an increase in the electrical conductivity in the growing medium, negatively affecting plant growth. However, blend 13 containing struvite, ammonium sulphate and potassium struvite expressed the best chemical composition with non-significant differences in the biomass from the positive controls, as it reduced the amount of potassium sulphate needed. Our results indicate that fertiliser blends containing P as struvite, N as ammonium nitrate or reduced amount of ammonium sulphate, and K as potassium struvite can substitute the use of mineral fertiliser blends to grow ornamental plant species as viola. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 2914 KiB

Open AccessArticle

Responses of Cereal Yields and Soil Carbon Sequestration to Four Long-Term Tillage Practices in the North China Plain

by Suying Chen, Peipei Yang, Yuming Zhang, Wenxu Dong, Chunsheng Hu and Oene Oenema

Agronomy 2022, 12(1), 176; https://doi.org/10.3390/agronomy12010176 - 12 Jan 2022

Cited by 13 | Viewed by 2377

Abstract

Current tillage practices in the important winter wheat–summer maize double cropping system of the North China Plain are under debate because of negative effects on soil quality and crop yield. Therefore, a long-term experiment was conducted from 2001 to 2018 to determine the [...] Read more.

Current tillage practices in the important winter wheat–summer maize double cropping system of the North China Plain are under debate because of negative effects on soil quality and crop yield. Therefore, a long-term experiment was conducted from 2001 to 2018 to determine the effects of soil conservation practices on crop yield and soil quality. The treatments were imposed following maize harvest and prior wheat seeding, and were defined as follows: (1) moldboard ploughing (0–20 cm) following maize straw removal (CK); (2) moldboard ploughing (0–20 cm) following maize straw return (CT); (3) rotary tillage following maize straw return (RT); and (4) no tillage with maize straw covering the soil surface (NT). Wheat straw was chopped and spread on the soil in all treatments and maize seeded without prior tillage. Wheat yields were higher in CT than RT and NT treatments (p < 0.05); NT had 18% lower wheat yields than CT. No significant differences were found between treatments in summer maize yields. The soil organic carbon (SOC) content in the surface layer (0–5 cm) was higher in NT and RT compared to CT and CK. However, SOC content in the 10–20 cm and 20–30 cm layers was lower in NT and RT compared to CT and CK. Similarly, available phosphorus in the surface soil was higher in NT and RT than in CT and CK. but the opposite was true for the lower soil layers. SOC stocks (0–30 cm) increased in all treatments, and were initially faster in NT and RT than in CT and CK. However, SOC stocks were higher in CT than in other treatments at the end of the experiment. This finding indicates that no tillage and reduced tillage decreased both wheat yields and soil C sequestration over time; it also indicates that CT was the most robust in terms of crop yields and soil C sequestration. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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24 pages, 4262 KiB

Open AccessArticle

The Effect of Cultivation Practices on Agronomic Performance, Elemental Composition and Isotopic Signature of Spring Oat (Avena sativa L.)

by Aleš Kolmanič, Lovro Sinkovič, Marijan Nečemer, Nives Ogrinc and Vladimir Meglič

Plants 2022, 11(2), 169; https://doi.org/10.3390/plants11020169 - 09 Jan 2022

Cited by 4 | Viewed by 3013

Abstract

The present study investigated the effects of cultivation practices on grain (oats) yield and yield components, such as straw yield, harvest index, thousand kernel weight, and plant lodging. In addition, multi-element composition and isotopic signature (δ¹³C, δ¹⁵N) of [...] Read more.

The present study investigated the effects of cultivation practices on grain (oats) yield and yield components, such as straw yield, harvest index, thousand kernel weight, and plant lodging. In addition, multi-element composition and isotopic signature (δ¹³C, δ¹⁵N) of the oat grains were studied. The spring oat cultivar ‘Noni’ was grown in a long-term field experiment during 2015–2020, using three management practices: control without organic amendment, incorporation of manure every third year and incorporation of crop residues/cover crop in the rotation. Synthetic nitrogen (N) (0, 55, 110 and 165 kg/ha) was applied during oat development in each system. Multi-element analysis of mature grains from two consecutive years (2016 and 2017) was performed using EDXRF spectroscopy, while stable isotope ratios of carbon (C) and nitrogen (N) were obtained using an elemental analyzer coupled to an isotope ratio mass spectrometer (EA/IRMS). The results show how cultivation practices affect yield components and isotopic and elemental signatures. Increasing the N rate improved both the oat grain and straw yields and increased susceptibility to lodging. The results show how the elemental content (Si, Ca, Zn, Fe, Ti, Br and Rb) in the oat grains were influenced by intensification, and a noticeable decrease in elemental content at higher N rates was the result of a dilution effect of increased dry matter production. The mean δ¹⁵N values in oat grains ranged from 2.5‰ to 6.4‰ and decreased with increasing N rate, while δ¹³C values ranged from −29.9‰ to –28.9‰. Based on the δ¹⁵N values, it was possible to detect the addition of synthetic N above an N rate of 55 kg/ha, although it was impossible to differentiate between different management practices using stable isotopes. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1113 KiB

Open AccessArticle

Effect of 50 Years of No-Tillage, Stubble Retention, and Nitrogen Fertilization on Soil Respiration, Easily Extractable Glomalin, and Nitrogen Mineralization

by Pramod Jha, Kuntal M. Hati, Ram C. Dalal, Yash P. Dang, Peter M. Kopittke, Brigid A. McKenna and Neal W. Menzies

Agronomy 2022, 12(1), 151; https://doi.org/10.3390/agronomy12010151 - 08 Jan 2022

Cited by 8 | Viewed by 2129

Abstract

In subtropical regions, we have an incomplete understanding of how long-term tillage, stubble, and nitrogen (N) fertilizer management affects soil biological functioning. We examined a subtropical site managed for 50 years using varying tillage (conventional till (CT) and no-till (NT)), stubble management (stubble [...] Read more.

In subtropical regions, we have an incomplete understanding of how long-term tillage, stubble, and nitrogen (N) fertilizer management affects soil biological functioning. We examined a subtropical site managed for 50 years using varying tillage (conventional till (CT) and no-till (NT)), stubble management (stubble burning (SB) and stubble retention (SR)), and N fertilization (0 (N0), 30 (N30), and 90 (N90) kg ha⁻¹ y⁻¹) to assess their impact on soil microbial respiration, easily extractable glomalin-related soil protein (EEGRSP), and N mineralization. A significant three-way tillage × stubble × N fertilizer interaction was observed for soil respiration, with NT+SB+N0 treatments generally releasing the highest amounts of CO₂ over the incubation period (1135 mg/kg), and NT+SR+N0 treatments releasing the lowest (528 mg/kg). In contrast, a significant stubble × N interaction was observed for both EEGRSP and N mineralization, with the highest concentrations of both EEGRSP (2.66 ± 0.86 g kg⁻¹) and N mineralization (30.7 mg/kg) observed in SR+N90 treatments. Furthermore, N mineralization was also positively correlated with EEGRSP (R² = 0.76, p < 0.001), indicating that EEGRSP can potentially be used as an index of soil N availability. Overall, this study has shown that SR and N fertilization have a positive impact on soil biological functioning. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 4140 KiB

Open AccessArticle

Absorption and Distribution of Calcium (⁴⁵Ca) Applied to the Surface of Orange (Citrus sinensis) Fruits at Different Developmental Stages

by Claudia Bonomelli, Victoria Fernández, Franco Capurro, Carola Palma, Ximena Videla, Ximena Rojas-Silva, Adriana Nario and Johanna Mártiz

Agronomy 2022, 12(1), 150; https://doi.org/10.3390/agronomy12010150 - 08 Jan 2022

Cited by 4 | Viewed by 2392

Abstract

In this study, the rate of absorption and transport of calcium (Ca) in orange fruits (Citrus sinensis cv. Fukumoto) after surface treatment with ⁴⁵Ca was evaluated by supplying treatments at different dates between fruit set and mid-phase II of growth (i.e., [...] Read more.

In this study, the rate of absorption and transport of calcium (Ca) in orange fruits (Citrus sinensis cv. Fukumoto) after surface treatment with ⁴⁵Ca was evaluated by supplying treatments at different dates between fruit set and mid-phase II of growth (i.e., 30, 44, 66 and 99 days after full bloom, DAFB). ⁴⁵Ca absorption was always detected, but ⁴⁵Ca application at the fruit set was associated with the highest rates of Ca transport into the pulp (39%) compared to the other treatments (17–19%). Scanning electron microscopy SEM) images of the fruit surface showed the occurrence of stomata along with the entire rind at all the developmental stages evaluated. However, from the beginning of stage I, stomata began to collapse and develop plugs, and this became frequent as the fruit age increased. From 44 DAFB, oil gland density increased, and Ca oxalates (CaOx) were found in the fruit flavedo and albedo. Fruit Ca (not labeled) concentration increased from fruit set (30 DAFB) to 99 DAFB, although oil gland formation and rind growth and differentiation likely hindered Ca transport to internal fruit tissues (pulp). The total Ca concentration in the pedicel was always higher than that in the fruit, with no differences between the first three treatments. The information obtained in this study may be essential for improving Ca fertilizer efficacy in citrus by spray applications. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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27 pages, 2393 KiB

Open AccessEditor’s ChoiceReview

Biostimulants in Viticulture: A Sustainable Approach against Biotic and Abiotic Stresses

by Eleonora Cataldo, Maddalena Fucile and Giovan Battista Mattii

Plants 2022, 11(2), 162; https://doi.org/10.3390/plants11020162 - 07 Jan 2022

Cited by 36 | Viewed by 7638

Abstract

Climate change and disproportionate anthropogenic interventions, such as the excess of phytopharmaceutical products and continuous soil tillage, are jeopardizing viticulture by subjecting plants to continuous abiotic stress. One of the main physiological repercussions of abiotic stress is represented by the unbalanced redox homeostasis [...] Read more.

Climate change and disproportionate anthropogenic interventions, such as the excess of phytopharmaceutical products and continuous soil tillage, are jeopardizing viticulture by subjecting plants to continuous abiotic stress. One of the main physiological repercussions of abiotic stress is represented by the unbalanced redox homeostasis due to the overproduction of reactive oxygen species (ROS), ultimately leading to a state of oxidative stress (detrimental to grape quality). To these are added the direct and indirect damages caused by pathogens (biotic stresses). In light of this scenario, it is inevitable that sustainable techniques and sensitivity approaches for environmental and human health have to be applied in viticulture. Sustainable viticulture can only be made with the aid of sustainable products. Biostimulant (PB) applications (including resistance inducers or elicitors) in the vineyard have become interesting maneuvers for counteracting vine diseases and improving grape quality. These also represent a partial alternative to soil fertilization by improving nutrient absorption and avoiding its leaching into the groundwater. Their role as elicitors has important repercussions in the stimulation of the phenylpropanoid pathway by triggering the activation of several enzymes, such as polyphenol oxidase, lipoxygenase, phenylalanine ammonia-lyase, and peroxidase (with the accumulation of phenolic compounds). The present review paper summarizes the PBs’ implications in viticulture, gathering historical, functional, and applicative information. This work aims to highlight the innumerable beneficial effects on vines brought by these products. It also serves to spur the scientific community to a greater contribution in investigating the response mechanisms of the plant to positive inductions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 1271 KiB

Open AccessArticle

Control of Apple Replant Disease Using Mixed Cropping with Brassica juncea or Allium fistulosum

by Lei Zhao, Gongshuai Wang, Xin Liu, Xuesen Chen, Xiang Shen, Chengmiao Yin and Zhiquan Mao

Agriculture 2022, 12(1), 68; https://doi.org/10.3390/agriculture12010068 - 05 Jan 2022

Cited by 4 | Viewed by 1987

Abstract

Evidence indicates that Allium and Brassica species which release bioactive compounds are widely used in bio-fumigation to suppress soil-borne diseases. However, the active molecules of such plant residues are easily volatilized. In this study, we conducted mixed cropping of the apple tree with [...] Read more.

Evidence indicates that Allium and Brassica species which release bioactive compounds are widely used in bio-fumigation to suppress soil-borne diseases. However, the active molecules of such plant residues are easily volatilized. In this study, we conducted mixed cropping of the apple tree with Allium fistulosum or Brassica juncea; the results demonstrated that such mixed cropping significantly improved the growth of the grafted apple seedlings and alleviated apple replant disease (ARD) for two years. The terminal-restriction fragment length polymorphism profile results showed that the soil fungal community demonstrated distinct variation and diversity in terms of composition. A. fistulosum and B. juncea significantly improved the Margalef, Pielou, and Shannon indices. In addition, the analyses of clone libraries showed that A. fistulosum and B. juncea promoted the proliferation of antagonistic fungi such as Mortierella, Trichoderma, and Penicillium, and inhibited the proliferation of pathogens such as Fusarium. Fusarium. Proliferatum(F. proliferatum) was abundant in replanted soil and proved to be an aggressive pathogen of apple seedlings. Our findings thus indicate that apple tree mixed cropping with A. fistulosum and B. juncea was an effective long-term method for modifying the resident fungal community and alleviating ARD. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 1612 KiB

Open AccessCase Report

A Heritage Agronomic Study as a Database for Monitoring the Soil Salinity of an Irrigated District in NE Spain

by Juan Herrero, Carmen Castañeda and Rosa Gómez-Báguena

Agronomy 2022, 12(1), 126; https://doi.org/10.3390/agronomy12010126 - 05 Jan 2022

Cited by 1 | Viewed by 1667

Abstract

This article presents and reviews the soil salinity data provided by a rescued vintage agronomic report on an irrigated area of 35,875 ha located in the center of the Ebro River basin, in the NE of mainland Spain. These data come from a [...] Read more.

This article presents and reviews the soil salinity data provided by a rescued vintage agronomic report on an irrigated area of 35,875 ha located in the center of the Ebro River basin, in the NE of mainland Spain. These data come from a soil sampling campaign conducted from May to the first half of July 1975 for the purpose of delineating saline and non-saline soils. The agronomic report was produced in response to demands from farmers to combat soil salinity, and represents the state of the art in those years for salinity studies. Our paper presents the scrubbed soil salinity data for this year, checking their consistency and locating the study sites. The main finding is the unearthing of this heritage report and the discussion of its soil salinity data. We show that the report supplies an assessment and a baseline for further soil salinity tracking by conducting new measurements either by direct soil sampling or by nondestructive techniques, providing an estimate of soil salinity at different locations. This task is feasible, as shown in our previously published articles involving nearby areas. A comparison of the salt amount in the soil over the years would provide a means to evaluate irrigation methods for sustainable land management. This comparison can be conducted simultaneously with analysis of other agricultural features described in the report for the irrigation district in 1975. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 1720 KiB

Open AccessArticle

Novel Approach for Statistical Interpretation: A Case Study from Long-Term Crop Production Experiments (Hungary)

by László Huzsvai, Safwan Mohammed, Endre Harsányi and Adrienn Széles

Horticulturae 2022, 8(1), 48; https://doi.org/10.3390/horticulturae8010048 - 04 Jan 2022

Cited by 1 | Viewed by 1650

Abstract

In recent decades, the agricultural sector has witnessed rapid technological interventions from field to the production stage. Thus, the importance of these technological interventions must be strictly evaluated. The traditional statistical method often deems low statistical differences as a significant one, which cannot [...] Read more.

In recent decades, the agricultural sector has witnessed rapid technological interventions from field to the production stage. Thus, the importance of these technological interventions must be strictly evaluated. The traditional statistical method often deems low statistical differences as a significant one, which cannot be considered effective from different perspectives. In this sense, the aim of this research was to develop a new statistical method for evaluating agricultural experiments based on different criteria; hence, the significant importance of the technological interventions can be clearly determined. Data were collected from of a long-term (13-year) crop production experiment (Central Europe, Hungary), which involved five different fertilization levels, along with non-fertilized treatment (control), two irrigation treatments (irrigated and non-irrigated), and 15–20 genotypes of maize. The output of this research showed that the classic statistical approach for testing the significant differences among treatments should be accompanied with our new suggested approach (i.e., professional test), which reflect whether treatments were professionally effective or not. Also, results showed that good statistical background is not enough for interoperating the analysis of agricultural experiments. This research suggested that erroneous conclusions can be avoided by merging classical and professional statistical tests, and correct recommendations could be provided to decision makers and farmers based on their financial resources. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 274 KiB

Open AccessArticle

Productivity of Rainfed Winter Wheat with Direct Sowing and Economic Efficiency of Diversified Fertilization in Arid Region of South Kazakhstan

by Sagadat Turebayeva, Aigul Zhapparova, Akbota Yerkin, Khaiyrnisa Aisakulova, Gainiya Yesseyeva, Anuarbek Bissembayev and Elmira Saljnikov

Agronomy 2022, 12(1), 111; https://doi.org/10.3390/agronomy12010111 - 02 Jan 2022

Cited by 7 | Viewed by 2047

Abstract

Reduced soil tillage is a powerful means to mitigate soil degradation. However, in arid climates, no-till rainfed technologies often result in yield drop due to lack of soil moisture and mineral nutrition. Rainfed production of winter wheat using direct sowing and diversified fertilization [...] Read more.

Reduced soil tillage is a powerful means to mitigate soil degradation. However, in arid climates, no-till rainfed technologies often result in yield drop due to lack of soil moisture and mineral nutrition. Rainfed production of winter wheat using direct sowing and diversified fertilization in South Kazakhstan was studied in 2019–2020. Eight field-scale treatments using nitrogen and phosphorus fertilizers were studied for biometric parameters of winter wheat. An economic profitability of the amendments used was assessed. The soil managed to accumulate productive moisture to support plants’ needs during formation of productive organs. Use of phosphorus fertilizer at direct sowing accelerated grain maturation, and the combination of phosphorus and nitrogen fertilizer lengthened the growing season. The highest production cost of 1 tonne of grain was in the plots that did not receive any amendments, and the lowest cost was in the treatment with use of plant growth stimulants together with micronutrient fertilizer. For the first time, optimization of the soil nutritional regime with consideration of the biological and phenological demands allowed for the balance of the plant nutrition and cost efficiency of grain production with direct sowing of winter wheat in dry conditions in South Kazakhstan. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

18 pages, 689 KiB

Open AccessArticle

Can Biofertilizers Reduce Synthetic Fertilizer Application Rates in Cereal Production in Mexico?

by Jesús Santillano-Cázares, Marie-Soleil Turmel, María Elena Cárdenas-Castañeda, Santiago Mendoza-Pérez, Agustín Limón-Ortega, Roberto Paredes-Melesio, Luis Guerra-Zitlalapa and Iván Ortiz-Monasterio

Agronomy 2022, 12(1), 80; https://doi.org/10.3390/agronomy12010080 - 30 Dec 2021

Cited by 5 | Viewed by 3278

Abstract

Biofertilizers are considered as potential supplements or alternatives to fertilizers. The objective of the present study is to evaluate different biofertilizers in combination with synthetic fertilizers on the yields of maize and wheat in several states in Mexico. Fourteen biofertilizer treatments plus a [...] Read more.

Biofertilizers are considered as potential supplements or alternatives to fertilizers. The objective of the present study is to evaluate different biofertilizers in combination with synthetic fertilizers on the yields of maize and wheat in several states in Mexico. Fourteen biofertilizer treatments plus a treatment with 100% the locally recommended fertilizer rate (RFR), another with 50% RFR (the control treatment), and one without any fertilizer (for a total of 17 treatments) were tested on maize and wheat in five states across Mexico. Field experiments were established in five states and several years for a total of 14 experiments in Mexico. In general, except for the experiments conducted in moderately low soil P conditions, Chiapas and Sonora (maize), no response to biofertilizers was observed in the remaining locations, through the years in wheat and maize. We conclude that in high input production systems, the biofertilizer response is more an exception than a rule with only 21% of the experiments showing a significant difference in favor of biofertilizers and only 4 of 15 products tested produced a yield response in more nitrogen deficient environments. Some products containing AMF may be beneficial in maize production systems with phosphorus deficient environments. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2212 KiB

Open AccessFeature PaperArticle

The Response of Antioxidant System of Drought-Stressed Green Pea (Pisum sativum L.) Affected by Watering and Foliar Spray with Silica Nanoparticles

by Rūta Sutulienė, Lina Ragelienė, Giedrė Samuolienė, Aušra Brazaitytė, Martynas Urbutis and Jurga Miliauskienė

Horticulturae 2022, 8(1), 35; https://doi.org/10.3390/horticulturae8010035 - 30 Dec 2021

Cited by 26 | Viewed by 3104

Abstract

Abiotic stress caused by drought impairs plant growth and reduces yields. This study aimed to investigate the impact of silica nanoparticles (SiO₂ NPs) through the adverse effects of drought on the growth, oxidative stress, and antioxidative response of pea ‘Respect’. Pea plants [...] Read more.

Abiotic stress caused by drought impairs plant growth and reduces yields. This study aimed to investigate the impact of silica nanoparticles (SiO₂ NPs) through the adverse effects of drought on the growth, oxidative stress, and antioxidative response of pea ‘Respect’. Pea plants were grown in a greenhouse before being watered (100 ± 1 mL per pot) or foliar sprayed (ca. 14 ± 0.5 mL plant⁻¹) with suspensions containing SiO₂ NPs (0, 12.5 ppm, 25 ppm, and 50 ppm) and were exposed to drought stress for 10 days. Drought stress was created by maintaining 30% of the soil moisture while the control was 80%. The growth parameters of pea grown under drought stress conditions were improved by spraying or watering plants with SiO₂ NPs (12.5, 25, and 50 ppm). At drought stress, peas treated with SiO₂ NPs (50 ppm) increased their relative water content by 29%, specific leaf area by 17%, and decreased root/shoot ratio by 4% as compared to plant non-treated with SiO₂ NPs. In addition, spraying or watering of SiO₂ NPs increased peas tolerance to drought by increasing the activity of antioxidant enzymes at least three times including catalase, ascorbate peroxidase, glutathione reductase, and superoxide dismutase, as well as reducing hydrogen peroxide and lipid peroxidation in plant tissue. It was observed the increase in total phenolic compounds and non-enzymatic antioxidant activity (DPPH, ABTS, FRAP) in peas treated with SiO₂ NPs under drought stress. The physiological response of peas to drought and the effects of SiO₂ NPs studied in this experiment based on the use of the concentration of 50 ppm nanoparticles can protect peas from the damaging effects of drought and could help reduce global food shortages. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 3158 KiB

Open AccessArticle

The Combined Effect of Biochar and Mineral Fertilizer on Triticale Yield, Soil Properties under Different Tillage Systems

by Luiza Usevičiūtė, Edita Baltrėnaitė-Gedienė and Dalia Feizienė

Plants 2022, 11(1), 111; https://doi.org/10.3390/plants11010111 - 30 Dec 2021

Cited by 8 | Viewed by 2179

Abstract

This study examined the effect of study time, biochar dose, and fertilization-tillage system on the improvement of sandy loam physical-chemical properties and triticale grain yield. The soil properties (water holding capacity (WHC), wettability, moisture content (MC), organic matter content (SOM), pH, and electrical [...] Read more.

This study examined the effect of study time, biochar dose, and fertilization-tillage system on the improvement of sandy loam physical-chemical properties and triticale grain yield. The soil properties (water holding capacity (WHC), wettability, moisture content (MC), organic matter content (SOM), pH, and electrical conductivity (EC) were monitored in short time intervals (after 3, 6, 12, and 24 months). Soil was tilled in two methods (shallow ploughless tillage and direct drilling), fertilized with nitrogen, phosphorus, and potassium (NPK) fertilizers, and amended with three hydrophobic pine wood biochar doses (0 t/ha; 5 t/ha; 15 t/ha). It was found that 15 t/ha biochar dose had the highest effect on the soil’s physical-chemical properties improvement (SOM increased by 33.7%, pH—by 6.84%, EC—by 23.4%, WHC—by 8.48%, and MC—by 21.8%) compared to the variants without biochar. Direct drilling, fertilization with NPK fertilizers and 15 t/ha biochar dose significantly influenced the rise of soil’s physical-chemical properties and triticale yield (3.51 t/ha). Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 477 KiB

Open AccessArticle

Biostimulant Effects of Micro Carbon Technology (MCT^®)-Based Fertilizers on Soil and Capsicum annuum Culture in Growth Chamber and Field

by Rafael Antón-Herrero, Carlos García-Delgado, Begoña Mayans, Raquel Camacho-Arévalo, Laura Delgado-Moreno and Enrique Eymar

Agronomy 2022, 12(1), 70; https://doi.org/10.3390/agronomy12010070 - 29 Dec 2021

Cited by 3 | Viewed by 1840

Abstract

Due to the environmental issues that conventional fertilization is causing, biostimulants are proposed as environmentally friendly alternative for crop nutrition in agriculture. The aim of this study was to determine the effects of new Micro Carbon Technology (MCT^®) fertilizers with biostimulant [...] Read more.

Due to the environmental issues that conventional fertilization is causing, biostimulants are proposed as environmentally friendly alternative for crop nutrition in agriculture. The aim of this study was to determine the effects of new Micro Carbon Technology (MCT^®) fertilizers with biostimulant activity based on humic acids biologically digested from leonardite on pepper plant growth in three different soils with different textures. The assays were performed under controlled conditions in a growth chamber and in commercial greenhouses in Spain. The effects on soil were analyzed after the addition of the fertilizers by microbial respiration and enzymatic activities (hydrolase, dehydrogenase and urease). For the plant assays, biometric parameters (fresh weight and fruit hardness) and foliar analysis (chlorophyll indices and nutrients) were evaluated. Under controlled conditions, the use of these biostimulants resulted in a greater soil microbial activity in a 24 h interval with increased soil enzymatic activity. In plants, a positive correlation was found between fertilizers with biostimulant activity and Dualex indices of leaves and content of macronutrients Ca and Mg. In commercial greenhouses, the fertilizers with biostimulant activity strongly depended on the soil texture. In conclusion, these products have real potential to replace conventional fertilizers in commercial production fields. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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17 pages, 4100 KiB

Open AccessArticle

Multi-Feature Optimization Study of Soil Total Nitrogen Content Detection Based on Thermal Cracking and Artificial Olfactory System

by He Liu, Qinghui Zhu, Xiaomeng Xia, Mingwei Li and Dongyan Huang

Agriculture 2022, 12(1), 37; https://doi.org/10.3390/agriculture12010037 - 29 Dec 2021

Cited by 3 | Viewed by 1718

Abstract

To improve the accuracy of detecting soil total nitrogen (STN) content by an artificial olfactory system, this paper proposes a multi-feature optimization method for soil total nitrogen content based on an artificial olfactory system. Ten different metal–oxide semiconductor gas sensors were selected to [...] Read more.

To improve the accuracy of detecting soil total nitrogen (STN) content by an artificial olfactory system, this paper proposes a multi-feature optimization method for soil total nitrogen content based on an artificial olfactory system. Ten different metal–oxide semiconductor gas sensors were selected to form a sensor array to collect soil gas and generate response curves. Additionally, six features such as the response area, maximum value, average differential coefficient, standard deviation value, average value, and 15th-second transient value of each sensor response curve were extracted to construct an artificial olfactory feature space (10 × 6). Moreover, the relationship between feature space and soil total nitrogen content was used to establish backpropagation neural network (BPNN), extreme learning machine (ELM), and partial least squares regression (PLSR) models were used, and the coefficient of determination (R²), root mean square error (RMSE), and the ratio of performance to deviation (RPD) were selected as prediction performance indicators. The Monte Carlo cross-validation (MCCV) and K-means improved leave-one-out cross-validation (K-means LOOCV) were adopted to identify and remove abnormal samples in the feature space and establish the BPNN model, respectively. There were significant improvements before and after comparing the two rejection methods, among which the MCCV rejection method was superior, where values for R², RMSE, and RPD were 0.75671, 0.33517, and 1.7938, respectively. After removing the abnormal samples, the soil samples were then subjected to feature-optimized dimensionality reduction using principal component analysis (PCA) and genetic algorithm-based optimization backpropagation neural network (GA-BP). The test results showed that after feature optimization the model indicators performed better than those of the unoptimized model, and the PLSR model with GA-BP for feature optimization had the best prediction effect, with an R² value of 0.93848, RPD value of 3.5666, and RMSE value of 0.16857 in the test set. R² and RPD values improved by 14.01% and 50.60%, respectively, compared with those before optimization, and RMSE value decreased by 45.16%, which effectively improved the accuracy of the artificial olfactory system in detecting soil total nitrogen content and could achieve more accurate quantitative prediction of soil total nitrogen content. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 3241 KiB

Open AccessArticle

Physiological and Morphological Responses of Okra (Abelmoschus esculentus L.) to Rhizoglomus irregulare Inoculation under Ample Water and Drought Stress Conditions Are Cultivar Dependent

by Amna Eltigani, Anja Müller, Benard Ngwene and Eckhard George

Plants 2022, 11(1), 89; https://doi.org/10.3390/plants11010089 - 28 Dec 2021

Cited by 4 | Viewed by 3705

Abstract

Okra is an important crop species for smallholder farmers in many tropical and subtropical regions of the world. Its interaction with mycorrhiza has been rarely studied, and little is known about its mycorrhizal dependency, especially under drought stress. In a glasshouse experiment, we [...] Read more.

Okra is an important crop species for smallholder farmers in many tropical and subtropical regions of the world. Its interaction with mycorrhiza has been rarely studied, and little is known about its mycorrhizal dependency, especially under drought stress. In a glasshouse experiment, we investigated the effect of Arbuscular Mycorrhiza Fungi (AMF) inoculation on growth, evapotranspiration, mineral nutrition and root morphology of five okra cultivars under ample water and drought stress conditions. ‘Khartoumia’, ‘HSD6719’, ‘HSD7058’, ‘Sarah’ and ‘Clemson Spineless’-cultivars commonly used by farmers in Sudan were chosen for their geographical, morphological and breeding background variations. The plants were either inoculated with R. irregulare or mock-inoculated. Seven weeks after seeding, the soil–water content was either maintained at 20% w/w or reduced to 10% w/w to impose drought stress. Drought stress resulted in plant P deficiency and decreased shoot dry biomass (DB), especially in HSD7058 and Clemson Spineless (69% and 56% decrease in shoot DB, in the respective cultivars). Plant inoculation with AMF greatly enhanced the shoot total content of P and the total DB in all treatments. The mycorrhizal dependency (MD)—the degree of total plant DB change associated with AM colonization—differed among the cultivars, irrespective of the irrigation treatment. Key determinants of MD were the root phenotype traits. Khartoumia (with the highest MD) had the lowest root DB, root-to-shoot ratio, and specific root length (SRL). Meanwhile, HSD6719 (with the lowest MD) had the highest respective root traits. Moreover, our data suggest a relationship between breeding background and MD. The improved cultivar Khartoumia showed the highest MD compared with the wild-type Sarah and the HSD7058 and HSD6719 landraces (higher MD by 46%, 17% and 32%, respectively). Interestingly, the drought-affected HSD7058 and Clemson Spineless exhibited higher MD (by 27% and 15%, respectively) under water-deficiency compared to ample water conditions. In conclusion, the mediation of drought stress in the okra plant species by AMF inoculation is cultivar dependent. The presence of AMF propagules in the field soil might be important for increasing yield production of high MD and drought susceptible cultivars, especially under drought/low P environments. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 9020 KiB

Open AccessArticle

Sustainability of the Soil Resource in Intensive Production with Organic Contributions

by Francia Deyanira Gaytán Martínez, Edgar Vladimir Gutiérrez Castorena, Vicente Vidal Encinia Uribe, Rigoberto Eustacio Vázquez Alvarado, Emilio Olivares Sáenz and Ma. del Carmen Gutiérrez Castorena

Agronomy 2022, 12(1), 67; https://doi.org/10.3390/agronomy12010067 - 28 Dec 2021

Cited by 4 | Viewed by 2007

Abstract

Organic agriculture is considered an alternative to sustainably preserve soil fertility. For 10 years, ongoing management with organic contributions was carried out in calcareous soil to support or increase fertility by applying 4 t ha⁻¹ of solid poultry manure to produce organic [...] Read more.

Organic agriculture is considered an alternative to sustainably preserve soil fertility. For 10 years, ongoing management with organic contributions was carried out in calcareous soil to support or increase fertility by applying 4 t ha⁻¹ of solid poultry manure to produce organic Nopal Verdura (Opuntia Ficus-Indica). In addition, during the 2018 cycle, corn was established as an alternative to diversify agricultural production; the crop was monitored by measuring agronomic variables and the normalized differential vegetation index to evaluate the development of different doses of organic inputs with poultry manure, foliar applications with biofertilizers, or in the irrigation system. The soil physical and chemical analysis was carried out from 2015 to 2020 to monitor nitrogen, phosphorus, potassium, calcium, magnesium, and organic matter before planting and after harvest. The results indicated an increase in nitrogen (>50%), calcium (>130%), and magnesium (>20%), while there was a decrease in phosphorus (50%), potassium (60%), and organic matter (18%). The agronomic management caused an increment of EC in the horizon Ap until 12.93 dS m⁻¹ at the end of each cycle due to the high ambient temperatures recorded and the inadequate irrigation water quality. We did not find significant differences (p > 0.05) in agronomic variables of corn with diverse contributions to organic. However, we obtained a maximum corn yield of 3.9 t ha⁻¹ and nopal production of 143 t ha⁻¹, despite problems of salinity in the horizons Ap during the agricultural cycle. Overall, processed poultry manure is a sustainable source of macroelements for the production of organic crops in calcisols; however, it is necessary to focus on and counteract potassium depletion and the increase in EC through appropriate agronomic management, with organic contributions, both solid and liquid, to increase or sustain production. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 2013 KiB

Open AccessArticle

Spearmint (Mentha spicata) Cultivation in Decoupled Aquaponics with Three Hydro-Components (Grow Pipes, Raft, Gravel) and African Catfish (Clarias gariepinus) Production in Northern Germany

by Ulrich Knaus, Julia Zimmermann, Samuel Appelbaum and Harry W. Palm

Sustainability 2022, 14(1), 305; https://doi.org/10.3390/su14010305 - 28 Dec 2021

Cited by 5 | Viewed by 2668

Abstract

Mint (Mentha spicata) was cultivated in different hydroponic components: grow pipes, a raft and an ebb-and-flood gravel substrate system irrigated with aquaculture effluents from intensive African catfish (Clarias gariepinus) production under decoupled aquaponic conditions in northern Germany. The spearmint [...] Read more.

Mint (Mentha spicata) was cultivated in different hydroponic components: grow pipes, a raft and an ebb-and-flood gravel substrate system irrigated with aquaculture effluents from intensive African catfish (Clarias gariepinus) production under decoupled aquaponic conditions in northern Germany. The spearmint grew well and plant heights above ground were not significantly different between the gravel (57.7 ± 13.1 cm), raft (58.0 ± 17.7 cm) and grow pipe components (63.6 ± 9.9 cm). Root lengths and root fresh weights were two-fold and four-fold higher in raft (64.3 ± 20.5 cm; 42.8 ± 29.9 g) and grow pipes (59.4 ± 15.2 cm; 41.3 ± 25.7 g) compared with gravel substrate (29.7 ± 7.8 cm; 9.4 ± 9.4 g; raft = grow pipes > gravel). Spearmint leaf number was significantly higher in the grow pipes (770.0 ± 224.4) than in the gravel substrate (499.8 ± 228.4) with intermediate values in the raft. Significantly highest mean fresh biomass was found in the raft (1275.6 ± 33.4 g), followed by grow pipes (1042.0 ± 35.8 g) and gravel substrate (686.3 ± 98.2 g; raft > grow pipes > gravel). M. spicata, under aquaponics, grows best in grow pipe and raft components. An increase in pipe diameter for the grow pipes and a reduction in the channel height for the raft components could optimize aquaponic culture conditions for both industrial production and the hobby sector in the future. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 2672 KiB

Open AccessArticle

Effects of Rice Husk Biochar Coated Urea and Anaerobically Digested Rice Straw Compost on the Soil Fertility, and Cyclic Effect of Phosphorus

by Ashoka Gamage, Ben Basnayake, Janendra De Costa and Othmane Merah

Plants 2022, 11(1), 75; https://doi.org/10.3390/plants11010075 - 27 Dec 2021

Cited by 14 | Viewed by 4452

Abstract

Fertilizer application in rice farming is an essential requirement. Most of the high-yielding varieties which are extensively grown throughout the country require recommended levels of fertilizers to obtain their potential yields. However, effective, and efficient ways of fertilizer application are of utmost importance. [...] Read more.

Fertilizer application in rice farming is an essential requirement. Most of the high-yielding varieties which are extensively grown throughout the country require recommended levels of fertilizers to obtain their potential yields. However, effective, and efficient ways of fertilizer application are of utmost importance. Coated fertilizers are used to reduce leaching nutrients and improve the efficiency of fertilizer. However, conventional coated fertilizers such as Sulphur coated urea and urea super granules are not popular among rice farmers in Sri Lanka owing to the high cost. Mixing urea-coated rice husk biochar causes a slow release of nitrogen fertilizer. This coated fertilizer and rice straw compost reduction the cost of importations of nitrogen-based fertilizers per unit area of cultivation. The study aimed to evaluate the effects of rice husk biochar coated urea and anaerobically digested rice straw compost on the soil fertility, and the cyclic effect of phosphorus. Concerning the pot experiment, rice grain yield was significantly higher in Rice husk biochar coated urea, triple super phosphate (TSP), and muriate of potash (MOP) with anaerobically digested rice straw compost. The lowest yield was observed in the control. The release of phosphate shows a cycle effect which is an important finding. Rice husk biochar coated urea can potentially be used as a slow-releasing nitrogen fertilizer. In addition, the urea coated with biochar is less costly and contributes to mitigating pollution of water bodies by inorganic fertilizers (NPK). Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 4031 KiB

Open AccessFeature PaperArticle

Effects of Varying Rates of Nitrogen and Biochar pH on NH₃ Emissions and Agronomic Performance of Chinese Cabbage (Brassica rapa ssp. pekinensis)

by Yun-Gu Kang, Jin-Hyuk Chun, Jae-Han Lee, Seong-Yong Park, Deogratius Luyima, Taek-Keun Oh and Yeo-Uk Yun

Agronomy 2022, 12(1), 61; https://doi.org/10.3390/agronomy12010061 - 27 Dec 2021

Cited by 6 | Viewed by 3085

Abstract

NH₃ emitted into the atmosphere undergoes intricate chemical reactions to form fine particulate matter PM_2.5. Nitrogen fertilizers are one of the major sources of gaseous ammonia. Recently, research into using biochar to lessen NH₃ emissions from agricultural land has [...] Read more.

NH₃ emitted into the atmosphere undergoes intricate chemical reactions to form fine particulate matter PM_2.5. Nitrogen fertilizers are one of the major sources of gaseous ammonia. Recently, research into using biochar to lessen NH₃ emissions from agricultural land has taken center stage and several studies have been executed in that regard. However, biochar’s capacity to reduce emissions of gaseous NH₃ from applied nitrogen fertilizers is affected by both soil and biochar properties. While the effects of soil properties on NH₃ volatilizations have been widely studied, the data concerning the effects of biochar properties on NH₃ volatilizations from the soil are still scanty. It is against this backdrop that this study examined the effects of biochar pH on emissions of NH₃ from the soil amended with varying quantities of nitrogen, as well as the impact on the growth and productivity of Chinese cabbage. To achieve the study objectives, acidic (pH 5.7), neutral (pH 6.7) and alkaline (pH 11.0) biochars were used and each was added to the soil at a rate of 1% (w/w). Nitrogen fertilizers were applied at three rates of 160, 320, 640 kg ha⁻¹. In comparison with the control, the acidic, neutral and alkaline biochar amendments reduced NH₃ emissions by up to 18%, 20% and 15%, respectively. However, only neutral biochar produced higher Chinese cabbage yields than the urea-only amendment and the Chinese cabbage yields increased with the increasing rates of nitrogen applied. Combined applications of neutral biochar and 640 kg/ha of nitrogen are recommended for optimal cabbage yields and low NH₃ emissions. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 22229 KiB

Open AccessArticle

Determination of Cover and Land Management Factors for Soil Loss Prediction in Cameron Highlands, Malaysia

by Mohd Amirul Mahamud, Noor Aida Saad, Roslan Zainal Abidin, Mohd Fazly Yusof, Nor Azazi Zakaria, Mohd Aminur Rashid Mohd Amiruddin Arumugam, Safari Mat Desa and Md. Nasir Md. Noh

Agriculture 2022, 12(1), 16; https://doi.org/10.3390/agriculture12010016 - 24 Dec 2021

Cited by 4 | Viewed by 3448

Abstract

Many new agricultural activities resulted in severe soil erosion across the Cameron Highlands’ land surface. Therefore, this study determines the cover (C) and land management (P) factors of the USLE for predicting soil loss risk in Cameron Highlands using [...] Read more.

Many new agricultural activities resulted in severe soil erosion across the Cameron Highlands’ land surface. Therefore, this study determines the cover (C) and land management (P) factors of the USLE for predicting soil loss risk in Cameron Highlands using a Geographic Information System (GIS). For this study, data from the Department of Agriculture Malaysia (DOAM) and the Department of Town and Country Planning Malaysia (PLANMalaysia) were used to generate several C&P factors in the Cameron Highlands. Data from both agencies have resulted in C factors with 0.01 to 1.00 and P factors with 0.30 to 0.49. Due to the cover and land management factor varies depending on the data collected by the various agencies, this study used the two data sets to come up with a C&P factor that accurately reflected both agricultural and urban growth effects. RKLS factors of USLE were obtained from the DOAM with values R (2375–2875), K (0.005), LS (2.5–25), respectively. The Cameron Highlands’ soil loss risk with these new C&P values resulted in a soil loss of 6.72 per cent (4547.22 hectares) from high to critical, with a percentage difference range of −0.77 to +3.37 under both agencies, respectively. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2112 KiB

Open AccessArticle

The Extended Effect of Top-Dressed Recovered Struvite Fertiliser on Residual Irish Grassland Soil Phosphorus Levels Compared to Commercial Phosphorus Fertiliser

by Ciarán O’Donnell, Denise Barnett, Joe Harrington and Niamh Power

Agronomy 2022, 12(1), 8; https://doi.org/10.3390/agronomy12010008 - 22 Dec 2021

Cited by 6 | Viewed by 2629

Abstract

Phosphorus (P) is an essential growth-limiting nutrient that cannot be synthetically produced. Mineral P fertilisers are typically applied to crops to sustain modern farming practice and food production. These fertilisers are generally derived from finite phosphate ore, for which there is much concern [...] Read more.

Phosphorus (P) is an essential growth-limiting nutrient that cannot be synthetically produced. Mineral P fertilisers are typically applied to crops to sustain modern farming practice and food production. These fertilisers are generally derived from finite phosphate ore, for which there is much concern over long-term sustainability. To address these concerns, various technologies have been developed to recover P from municipal wastewater treatment plants. One product recovered from these processes is struvite, which is a precipitate formed of magnesium, ammonium, and phosphate. To analyse the fertilisation value of the recovered struvite, field trials were conducted on perennial ryegrass (Lolium perenne) over three growing seasons, analysing the dry matter yield of recovered struvite fertiliser. The trial was based on a three-crop silage system designed to mimic typical Irish agricultural practice. This research highlights that recovered struvite as a fertiliser provides additional benefits including increasing the soil P levels. The struvite test case produced a statistically significantly increased soil P level from the baseline of Morgan’s extractable P content of 6.4 mg/L to the optimum Morgan’s soil P level of 11.13 mg/L. The findings of this research provide insight into the added benefits of recovered struvite fertiliser as a sustainable renewable P fertiliser. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2701 KiB

Open AccessArticle

Acaulospora as the Dominant Arbuscular Mycorrhizal Fungi in Organic Lowland Rice Paddies Improves Phosphorus Availability in Soils

by Khachonphong Nopphakat, Phanthipha Runsaeng and Lompong Klinnawee

Sustainability 2022, 14(1), 31; https://doi.org/10.3390/su14010031 - 21 Dec 2021

Cited by 8 | Viewed by 3646

Abstract

Flooding in rainfed lowlands greatly impairs the mutualistic relationship between indigenous arbuscular mycorrhizal fungi (AMF) and rice. In flooded soils, root colonization by AMF is arrested, but some AMF genera, defined as the core AMF, remain present. However, the core AMF in rainfed [...] Read more.

Flooding in rainfed lowlands greatly impairs the mutualistic relationship between indigenous arbuscular mycorrhizal fungi (AMF) and rice. In flooded soils, root colonization by AMF is arrested, but some AMF genera, defined as the core AMF, remain present. However, the core AMF in rainfed lowlands and their symbiotic roles remain unknown. Here, we showed that Acaulospora fungi were the core AMF in rice seedling roots of the Sangyod Muang Phatthalung (SMP) landrace rice variety grown in non-flooded and flooded paddy soils. Subsequently, indigenous Acaulospora spores were propagated by trap cultures using maize as the host plants. Therefore, to clarify the roles of cultured Acaulospora spores in a symbiotic partnership, the model japonica rice variety Nipponbare was grown in sterile soil inoculated with Acaulospora spores, and recolonized with a native microbial filtrate from the organic rice paddy soil. Our data demonstrated that the inoculation of Acaulospora spores in well-drained soil under a nutrient-sufficient condition for six weeks enabled 70 percent of the rice roots to be colonized by the fungi, leading to higher phosphate (Pi) accumulation in the mycorrhizal roots. Unexpectedly, the growth of rice seedlings was significantly suppressed by inoculation while photosynthetic parameters such as fractions of incoming light energy and relative chlorophyll content were unaltered. In the soil, the Acaulospora fungi increased soil phosphorus (P) availability by enhancing the secretion of acid phosphatase in the mycorrhizal roots. The findings of this work elucidate the symbiotic roles of the dominant Acaulospora fungi from lowland rice paddies. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 9213 KiB

Open AccessArticle

Isolation and Characterization of Plant Growth-Promoting Compost Bacteria That Improved Physiological Characteristics in Tomato and Lettuce Seedlings

by Betsie Martínez-Cano, Juan Fernando García-Trejo, Arantza Elena Sánchez-Gutiérrez, Manuel Toledano-Ayala and Genaro M. Soto-Zarazúa

Agriculture 2022, 12(1), 3; https://doi.org/10.3390/agriculture12010003 - 21 Dec 2021

Cited by 7 | Viewed by 4634

Abstract

Currently, agricultural systems are inadequate to meet the demand of the population, coupled with the constant degradation of natural resources. Therefore, it is necessary to explore alternatives to increase the productivity and quality of crops with minimal environmental impact. The use of plant [...] Read more.

Currently, agricultural systems are inadequate to meet the demand of the population, coupled with the constant degradation of natural resources. Therefore, it is necessary to explore alternatives to increase the productivity and quality of crops with minimal environmental impact. The use of plant growth-promoting bacteria can provide solutions to some agri-environmental problems and replace or minimize conventional agricultural practices. In this study, a Bacillus pumilus strain with plant growth-promoting properties was isolated from mature compost. In vitro, the ability of Bacillus pumilus to solubilize phosphate, inhibit the growth of phytopathogenic fungi, and its effect on the germination of tomato and lettuce seeds was evaluated. In vivo, its effect on stem thickness, height, and the number of leaves of tomato and lettuce seedlings was studied. The results show that, in vitro, Bacillus pumilus solubilizes phosphate, inhibits the growth of the fungus Fusarium oxysporum, and increases the germination percentage of tomato seeds. The results, in vivo, demonstrate that the bacteria increases the stem thickness of tomato seedlings, while, in lettuce, it increases the stem thickness and the number of leaves. The outcome implies that Bacillus pumilus has properties as a plant growth promoter and can be used as a promising inoculant to enhance the growth of tomato and lettuce seedlings. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 11877 KiB

Open AccessArticle

Agronomic Efficiency Losses by Ammonia Emission from Staple Crops in China as Response to Various Mitigation Strategies: A Meta-Analysis Study

by Ahmed I. Abdo, Daolin Sun, El-Sayed E. A. El-Sobky, Hui Wei and Jiaen Zhang

Agronomy 2021, 11(12), 2593; https://doi.org/10.3390/agronomy11122593 - 20 Dec 2021

Cited by 1 | Viewed by 2628

Abstract

Economic losses and environmental hazards are meaningful problems of emitted ammonia induced by extensive use of synthetic nitrogen fertilizers. The concept presented as yield scaled fertilizer productivity (YSFP) in our meta-analysis in addition to nitrogen use efficiency (NUE), nitrogen agronomic efficiency (NAE), and [...] Read more.

Economic losses and environmental hazards are meaningful problems of emitted ammonia induced by extensive use of synthetic nitrogen fertilizers. The concept presented as yield scaled fertilizer productivity (YSFP) in our meta-analysis in addition to nitrogen use efficiency (NUE), nitrogen agronomic efficiency (NAE), and productivity of applied nitrogen (PAN) were used to weight ammonia emission (AV)-induced reductions in wheat, maize, and rice production. The comprehensive meta-analysis was used to weight the reductions in these parameters by AV as the difference between observed means of the collected studies and their adjusted means using AV factor. There were higher reductions in agronomic production induced by AV in rice than maize and wheat. AV-induced reductions in PAN of rice, maize, and wheat were decreased by 4.99, 3.71, and 2.42 (kg grains kg⁻¹ N), respectively. YSFP and PAN recorded the highest sensitivity to AV in wheat (R² = 0.88 for both) and rice (R² = 0.92 and 0.89, respectively), while NUE was the most efficient parameter in weighting AV induced agronomic effects in maize (R² = 0.81). Slow-released N fertilizers resulted in the lowest reductions in AV induced agronomic losses followed by organic amendments and then urea while using other synthetic fertilizers recorded the highest reductions by 3.90, 6.40, 1.41, and 4.70 in YSFP, NUE, NAE, and PAN, respectively. Inhibitors had the highest effect on mitigating AV induced agronomic losses compared with biochar and mulching and affected the parameters following that order as percentages of no amendments, YSFP (52.63%) > PAN (47.18%) > NUE (40.83%) > NAE (38.75%). This study outlines the reductions in agronomic production induced by AV and weights the efficiency of various mitigation strategies under various agronomic conditions. The results proved the efficiency of YSFP with NUE parameters to weight the effect of AV on crop yield, while suggesting to find out more applicable parameters in further studies. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 620 KiB

Open AccessArticle

Interactive Effects of Organic Fertilizers and Drought Stress on Growth and Nutrient Content of Brassica juncea at Vegetative Stage

by Addisie Geremew, Laura Carson, Selamawit Woldesenbet, Charles Carpenter, Elisha Peace and Aruna Weerasooriya

Sustainability 2021, 13(24), 13948; https://doi.org/10.3390/su132413948 - 17 Dec 2021

Cited by 4 | Viewed by 3329

Abstract

With the ongoing climate change scenario and alarmingly increased land degradation, understanding complex interactions of drought stress and organic fertilizers on morpho-physiological traits and dynamics of nutrient concentration is pivotal for sustainable production leafy vegetables such as mustard (Brassica juncea). Thus, [...] Read more.

With the ongoing climate change scenario and alarmingly increased land degradation, understanding complex interactions of drought stress and organic fertilizers on morpho-physiological traits and dynamics of nutrient concentration is pivotal for sustainable production leafy vegetables such as mustard (Brassica juncea). Thus, this study evaluated the effect of drought stress and organic fertilizers on B. juncea growth, physiology, and dynamics of nutrient concentration at the vegetative stage. The plants were exposed to three water stress levels (well-watered (100% field capacity, FC), mild (50% FC), and severe (25% FC) supplemented with three organic fertilizers (chitosan, ultra green, and home-grown natural vegetable foods) either individually or in combination during the vegetative growth stage. Water stress had a negative effect on growth and physiological traits, and macro- and micronutrients of mustard. However, the ameliorative effects of fertilizer application were revealed by improved plant height, leaf area, relative water content, membrane stability index, and chlorophyll content from 9.7% to 26.9%, 28% to 32.72%, 7.97% to 39.51%, 7.93% to 39.66%, and 29.68% to 56.53%, respectively. Analysis of variance revealed a significant effect of soil moisture level, fertilizer type and their interaction on content of macronutrients (Ca, K, P, N, C, S, Na, Mg) and micronutrients (Fe, Zn) in mustard leaves. However, there was no significant effect detected for Cu across all factors as well the interaction effect on Mn. Overall, our results indicated that application of organic fertilizers enables mustard plant to withstand the deleterious effect of drought stress, resulting in improved growth and physiological traits as well as leaf nutrient content. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 58618 KiB

Open AccessArticle

Phosphogypsum Organic, a Byproduct from Rare-Earth Metals Processing, Improves Plant and Soil

by Mohamed Musa Hanafi, Parisa Azizi and Jeyanny Vijayanathan

Agronomy 2021, 11(12), 2561; https://doi.org/10.3390/agronomy11122561 - 16 Dec 2021

Cited by 7 | Viewed by 2281

Abstract

Phosphogypsum organic (PG organic) is a soil conditioner, derived from residues, water leach purification (WLP) and neutralisation underflow (NUF) from rare-earth metals processing in combination with composted organic material. There was no report available with regards to the effectiveness of this byproduct for [...] Read more.

Phosphogypsum organic (PG organic) is a soil conditioner, derived from residues, water leach purification (WLP) and neutralisation underflow (NUF) from rare-earth metals processing in combination with composted organic material. There was no report available with regards to the effectiveness of this byproduct for crops improvement in a sandy soil texture. Therefore, a field trial involving a multi-crop was conducted by the addition of PG organic on a sandy texture soil for 23-month period. Guinea grass or guinea grass intercropping with teak wood trees, corn and kenaf showed an improvement in cumulative fresh yield in plot treated with PG organic either with a half- or full-fertilizer recommended rate for the respective crop as compared to control. The same trend was also observed in teak wood trees in hole planting systems and pandan coconut seedlings in the polybags. Application of PG organic in each season showed a consistently higher cumulative fresh yield or yield for certain crop types due to soil ability to maintain the soil pH buffering capacity (pH 5.8–6.0). Therefore, the application of PG organic as soil conditioner promotes plant growth and development due to the improvement of soil condition by creating suitable ecosystem for nutrients absorption by roots. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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8 pages, 604 KiB

Open AccessArticle

Addition of Phosphatases and Phytases to Mature Compost to Increase Available Phosphorus: A Short Study

by Adrian Esteban Ortega-Torres, Enrique Rico-García, Rosario Guzmán-Cruz, Irineo Torres-Pacheco, Erik Gustavo Tovar-Pérez and Ramón Gerardo Guevara-González

Agronomy 2021, 11(12), 2555; https://doi.org/10.3390/agronomy11122555 - 16 Dec 2021

Cited by 2 | Viewed by 2031

Abstract

Agriculture depends on fertilizers to provide nutrients for plants. Phosphorus (P) is one of these nutrients and is the second-most necessary for plant growth. Global production of P fertilizer is concentrated in Morocco, China and the United States. A large amounts of P [...] Read more.

Agriculture depends on fertilizers to provide nutrients for plants. Phosphorus (P) is one of these nutrients and is the second-most necessary for plant growth. Global production of P fertilizer is concentrated in Morocco, China and the United States. A large amounts of P resources are found in organic wastes that can be transformed through phosphate-solubilizing microorganisms during the composting process. In this study, we first determined the enzymatic activity of phosphatases and phytase from Pseudomonas aeruginosa ATC 15442. Second, we evaluated the mineralization of P in mature compost when inoculated with P. aeruginosa ATC 15442, phytases, a cocktail of phosphate-solubilizing enzymes and their combinations. Finally, we evaluated different concentrations of the cocktail trying to release more P in the compost. The results indicated that P. aeruginosa exuded alkaline phosphatases, acid phosphatase, neutral phosphatase and phytase. The enzymatic cocktail increased inorganic P (Pi) when added to the mature compost: this was able to release up to 95% more Pi in the compost compared to the amount of Pi released in the control compost. The current study demonstrated the importance of adding the cocktail to enhance Pi in mature compost; however, further studies are required to confirm the results and practical applications. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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24 pages, 495 KiB

Open AccessArticle

Investigating the Quality and Efficiency of Biosolid Produced in Qatar as a Fertilizer in Tomato Production

by Majeed Ali, Talaat Ahmed, Mohammed Abu-Dieyeh and Mohammad A. Al-Ghouti

Agronomy 2021, 11(12), 2552; https://doi.org/10.3390/agronomy11122552 - 15 Dec 2021

Cited by 3 | Viewed by 2703

Abstract

This study evaluated biosolid quality over time and the efficiency of using amounts (5 and 7 kg/m²) of municipal class A biosolids in Qatar to fertilize tomato plants (Solanum lycopersicum). Random samples were subjected to physical and chemical analysis, [...] Read more.

This study evaluated biosolid quality over time and the efficiency of using amounts (5 and 7 kg/m²) of municipal class A biosolids in Qatar to fertilize tomato plants (Solanum lycopersicum). Random samples were subjected to physical and chemical analysis, which revealed excellent particle uniformity and stability with minor odor defects. The analysis confirmed the product was nutrient-rich while pollutant levels were below the international standards. The nominated rates were used to fertilize tomato plants in pots grown in a greenhouse for four months with a control treatment of manure and Peat-Moss, before measuring the plant biological characteristics. Plants were examined via chemical analysis of nutrients and pollutants both for the whole plant and for stems, fruits, and leaves. Results indicated that both experimental treatments enhanced plant growth and development as compared to the control treatment. However, the chemical analyses also revealed levels of zinc, copper, and manganese in the plant fruits that were well in excess of the maximum acceptable levels, as defined by international health organizations. This study found that while the application of class A biosolids as organic fertilizer for tomato plants greatly enhanced the overall plant growth, the plant fruits contained toxic levels of trace heavy metals. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 3478 KiB

Open AccessArticle

Genetic Variation for Traits Related to Phosphorus Use Efficiency in Lens Species at the Seedling Stage

by Vinita Ramtekey, Ruchi Bansal, Muraleedhar S. Aski, Deepali Kothari, Akanksha Singh, Renu Pandey, Kuldeep Tripathi, Gyan P. Mishra, Shiv Kumar and Harsh Kumar Dikshit

Plants 2021, 10(12), 2711; https://doi.org/10.3390/plants10122711 - 10 Dec 2021

Cited by 6 | Viewed by 2752

Abstract

Phosphorus (P) is an essential, non-renewable resource critical for crop productivity across the world. P is immobile in nature and, therefore, the identification of novel genotypes with efficient P uptake and utilization under a low P environment is extremely important. This study was [...] Read more.

Phosphorus (P) is an essential, non-renewable resource critical for crop productivity across the world. P is immobile in nature and, therefore, the identification of novel genotypes with efficient P uptake and utilization under a low P environment is extremely important. This study was designed to characterize eighty genotypes of different Lens species for shoot and root traits at two contrasting levels of P. A significant reduction in primary root length (PRL), total surface area (TSA), total root tips (TRT), root forks (RF), total dry weight (TDW), root dry weight (RDW) and shoot dry weight (SDW) in response to P deficiency was recorded. A principal component analysis revealed that the TDW, SDW and RDW were significantly correlated to P uptake and utilization efficiency in lentils. Based on total dry weight (TDW) under low P, L4727, EC718309, EC714238, PL-97, EC718348, DPL15, PL06 and EC718332 were found promising. The characterization of different Lens species revealed species-specific variations for the studied traits. Cultivated lentils exhibited higher P uptake and utilization efficiency as compared to the wild forms. The study, based on four different techniques, identified EC714238 as the most P use-efficient genotype. The genotypes identified in this study can be utilized for developing mapping populations and deciphering the genetics for breeding lentil varieties suited for low P environments. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1276 KiB

Open AccessArticle

Nitrogen Fertiliser Immobilisation and Uptake in the Rhizospheres of Wheat and Canola

by Ben A. Rigby, Niloufar Nasrollahi, Corinne Celestina, James R. Hunt, John A. Kirkegaard and Caixian Tang

Agronomy 2021, 11(12), 2507; https://doi.org/10.3390/agronomy11122507 - 10 Dec 2021

Viewed by 2386

Abstract

Immobilisation of fertiliser nitrogen (N) by soil microorganisms can reduce N availability to crops, decreasing growth and yield. To date, few studies have focussed on the effect of different plant species on immobilisation of fertiliser N. Canola (Brassica napus) is known [...] Read more.

Immobilisation of fertiliser nitrogen (N) by soil microorganisms can reduce N availability to crops, decreasing growth and yield. To date, few studies have focussed on the effect of different plant species on immobilisation of fertiliser N. Canola (Brassica napus) is known to influence the soil microbiome and increase mineral N in soil for future crops compared with cereals. We tested the hypothesis that canola can reduce immobilisation of fertiliser N by influencing the composition of the rhizosphere microbiome. To investigate this, we conducted a glasshouse soil column experiment comparing N fertiliser uptake between canola and wheat (Triticum aestivium) and partitioning of fertiliser N between plants and microorganisms. Plants were grown in soil to which high C:N ratio wheat residues and ¹⁵N-labelled urea fertiliser were applied. There was no difference between wheat and canola in fertiliser N uptake despite differences in fungal community composition and the carbon metabolising enzyme alpha-glucosidase in the rhizosphere. Canola obtained more soil-derived N than wheat. There was no significant difference in the rhizosphere bacterial communities present between wheat and canola and unplanted controls. Our results highlight the capacity of canola to increase mineralisation of soil N compared with wheat although the study could not describe the microbial community which facilitated this increase. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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25 pages, 24589 KiB

Open AccessEditor’s ChoiceArticle

Conceptual Design of a Comprehensive Farm Nitrogen Management System

by Fabian Weckesser, Frank Leßke, Marco Luthardt and Kurt-Jürgen Hülsbergen

Agronomy 2021, 11(12), 2501; https://doi.org/10.3390/agronomy11122501 - 09 Dec 2021

Cited by 9 | Viewed by 3435

Abstract

Data that are required for nutrient management are becoming increasingly available in digital format, leading to a high innovation potential for digital nitrogen (N) management applications. However, it is currently difficult for farmers to analyze, assess, and optimize N flows in their farms [...] Read more.

Data that are required for nutrient management are becoming increasingly available in digital format, leading to a high innovation potential for digital nitrogen (N) management applications. However, it is currently difficult for farmers to analyze, assess, and optimize N flows in their farms using the existing software. To improve digital N management, this study identified, evaluated, and systematized the requirements of stakeholders. Furthermore, digital farm N management tools with varying objectives in terms of system boundaries, data requirements, used methods and algorithms, performance, and practicality were appraised and categorized. According to the identified needs, the concept of a farm N management system (FNMS) software is presented which includes the following modules: (1) management of site and farm data, (2) determination of fertilizer requirements, (3) N balancing and cycles, (4) N turnover and losses, and (5) decision support. The aim of FNMS is to support farmers in their farming practices for increasing N efficiency and reducing environmentally harmful N surpluses. In this study, the conceptual requirements from the agricultural and computer science perspectives were determined as a basis for developing a consistent, scientifically sound, and user-friendly FNMS, especially applicable in European countries. This FNMS enables farmers and their advisors to make knowledge-based decisions based on comprehensive and integrated data. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 397 KiB

Open AccessEditor’s ChoiceArticle

The Effect of Zinc Oxide Nanoparticles for Enhancing Rice (Oryza sativa L.) Yield and Quality

by Haipeng Zhang, Rui Wang, Zhiqing Chen, Peiyuan Cui, Hao Lu, Yanju Yang and Hongcheng Zhang

Agriculture 2021, 11(12), 1247; https://doi.org/10.3390/agriculture11121247 - 09 Dec 2021

Cited by 35 | Viewed by 5138

Abstract

Zinc oxide nanoparticles (ZnO NPs) have been applied widely in agriculture, and many studies were conducted to evaluate the effect of ZnO NPs on plant growth. So far, few studies have been investigated with regard to the potential effect of ZnO NPs on [...] Read more.

Zinc oxide nanoparticles (ZnO NPs) have been applied widely in agriculture, and many studies were conducted to evaluate the effect of ZnO NPs on plant growth. So far, few studies have been investigated with regard to the potential effect of ZnO NPs on cereal yield formation or Zn content in grains. Herein, we used a pot experiment, which was conducted involving five dosages of Zn (0.3, 0.6, 1.2, 2.4, and 4.8 g Zn pot⁻¹), to evaluate the impacts which ZnO NPs made in rice yield, dry matter accumulation, rice quality and grain Zn contents. The results demonstrated that ZnO NPs increased the production of grain, dry matter accumulation and particulate Zn content. Compared with control treatment, ZnO NPs application presented higher rice yield with more panicle number (4.83–13.14%), spikelets per panicle (4.81–10.69%), 1000-grain weight (3.82–6.62%) and filled grain rate (0.28–2.36%). Additionally, the dry jointing, heading and mature periods, LAI, SPAD values, and photosynthetic potentials of ZnO NPs were all significantly higher relative to treatment without ZnO NPs. The more photosynthetic substances and higher dry matter accumulated in the whole rice growing stage resulted in higher rice grain yield. Furthermore, ZnO NPs increased brown rice rate, milled rice rate, head rice rate, chalkiness size, chalkiness grain rate, chalkiness degree, amylose content and protein content, improving rice processing and appearance qualities. For the Zn nutrition in rice grain, ZnO NPs application significantly increased the Zn content of edible polished rice and promoted the relocation of Zn from the aleurone layer. This study effectively demonstrated that ZnO NPs could be a potential high-performed fertiliser for enhancing rice yield and quality. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1944 KiB

Open AccessFeature PaperArticle

Macroelements and Microelements in the Soil and Their Relationship with the Content of Steviol Glucosides in Stevia rebaudiana Bert from Five Regions of Colombia

by Enrique Combatt Caballero, Jaime Hernández Burgos, Alfredo Jarma-Orozco, Juan Jaraba Navas and Luis Rodríguez Páez

Horticulturae 2021, 7(12), 547; https://doi.org/10.3390/horticulturae7120547 - 03 Dec 2021

Cited by 2 | Viewed by 2865

Abstract

This study was conducted to determine the effect of edaphic environmental conditions in the concentration of principal steviol glycosides and Stevia rebaudiana Bert yield, utilizing leaves from five Colombian regions. The structure of the experiment was a randomized complete block design with two [...] Read more.

This study was conducted to determine the effect of edaphic environmental conditions in the concentration of principal steviol glycosides and Stevia rebaudiana Bert yield, utilizing leaves from five Colombian regions. The structure of the experiment was a randomized complete block design with two treatments in a 5 × 2 factorial arrangement (5 locations × 2 radiation levels). In each experimental unit (UE), five healthy plants of similar physiological growth age were selected for the extraction of total glycosides (GT), stevioside (Stv), rebaudioside A (Rb-A),and leaf yield. Results were analyzed with the SAS statistical package (version 9.1). Concentrations of total glycosides and rebaudioside A showed a positive effect with the increase of nitrogen (N), phosphorus (P), magnesium (Mg), and copper (Cu). Therefore, they are important in the available phase of the soil to obtain an increase in these glycosides. Meanwhile, boron (B) presented a negative correlation under these conditions. For the production of stevioside, N, Mg, manganese (Mn) had a positive correlation, and calcium (Ca) and sodium (Na) had a negative correlation. Similarly, for leaf yields by locality, it was found that N, Ca, Mg, and B have a positive correlation with leaf production, while Mg, Mn, and iron (Fe) negatively correlate with biomass gain.The cultivation of stevia can be established in different soil conditions, precipitation and solar radiation in Colombia. Therefore, it is necessary to advance fertilization plans with these nutrients, considering the response of these metabolites to their application. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 2343 KiB

Open AccessArticle

Concentration of Nutrients in Leaves, Flowers, and Fruits of Genotypes of Coffea canephora

by Millena Monteiro dos Santos, Cleidson Alves da Silva, Eduardo France Oza, Ivoney Gontijo, José Francisco Teixeira do Amaral and Fábio Luiz Partelli

Plants 2021, 10(12), 2661; https://doi.org/10.3390/plants10122661 - 03 Dec 2021

Cited by 7 | Viewed by 2644

Abstract

It is important to consider the nutritional demand among genotypes of the same species to achieve high yields. Thus, the objective of this study was to determine the concentration of nutrients in leaves, flowers, grains, and fruit straw in conilon coffee genotypes. The [...] Read more.

It is important to consider the nutritional demand among genotypes of the same species to achieve high yields. Thus, the objective of this study was to determine the concentration of nutrients in leaves, flowers, grains, and fruit straw in conilon coffee genotypes. The experiment was carried out under a randomized block design, with three replications and the evaluation of nine genotypes. Leaf collections were carried out every three months, from August 2019 to May 2020. Flowers were collected at flowering in July 2019 and fruits in June 2020, upon complete maturation of the genotypes. The materials were dried in an oven and sent for laboratory analysis to determine the nutritional content. Data were subjected to analysis of variance followed by a comparison of means and estimates of genetic parameters and clustering using the hierarchical method (UPGMA). The nutrients found in the highest concentrations in the evaluated plant organs were N and K for macronutrients and Fe for micronutrients. For the leaves, the concentrations of the main nutrients were high in the first and reduced in the last evaluated periods, possibly due to mobilization to the fruits. Considering all the plant tissues evaluated, the order of concentration of macronutrients and micronutrients was N > K > Ca > P = Mg = S and Fe > B > Mn > Cu > Zn, respectively. For a nutritional diagnosis, it is important to take comparisons of the genetic diversity and evaluation periods into consideration. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 16570 KiB

Open AccessArticle

Green Manure Amendment Can Reduce Nitrogen Fertilizer Application Rates for Oilseed Rape in Maize–Oilseed Rape Rotation

by Chiming Gu, Wei Huang, Yue Li, Yinshui Li, Changbin Yu, Jing Dai, Wenshi Hu, Xiaoyong Li, Margot Brooks, Lihua Xie, Xing Liao and Lu Qin

Plants 2021, 10(12), 2640; https://doi.org/10.3390/plants10122640 - 01 Dec 2021

Cited by 3 | Viewed by 2800

Abstract

Excessive use of chemical fertilizers has led to a reduction in the quality of arable land and environmental pollution. Using green manure to replace chemical fertilizers is one of the most effective solutions. To study the effect of green manure on the requirement [...] Read more.

Excessive use of chemical fertilizers has led to a reduction in the quality of arable land and environmental pollution. Using green manure to replace chemical fertilizers is one of the most effective solutions. To study the effect of green manure on the requirement for nitrogen fertilizer in oilseed rape, a field experiment with maize–oilseed rape rotation was conducted. Green manure was intercropped between rows of maize and returned after the maize harvest, with no green manure intercropped as control. Different nitrogen fertilizer treatments (0, 65%, 75% and 100% N rates, respectively) were applied during the oilseed rape season. The results showed that with a 35% reduction in nitrogen application rate, the rapeseed grain yield was significantly higher with the maize intercropping with green manure returned to the field than with the maize monocropping treatment at the same nitrogen level. Under conditions of intercropping and return of green manure, compared with the full standard rate of nitrogen fertilizer treatment, a reduction in nitrogen application of 25–30% in the rape season had no significant effect on rape yield. The agronomic efficiency of nitrogen fertilizer on oilseed rape increased significantly, by 47.61–121%, with green manure incorporation. In addition, green manure incorporation significantly increased the soil organic matter content and the soil-available nitrogen content when chemical nitrogen fertilization was abandoned. Benefit analysis showed that a 25–35% reduction in chemical nitrogen fertilizer applied to oilseed rape crops could be achieved by intercropping green manure in the maize season before the sowing of rapeseed in the experimental area. In the long-term, this measure would increase nitrogen utility, reduce production costs, and have concomitant environmental benefits of improving the quality of cultivated land. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 2069 KiB

Open AccessArticle

Impact of the Legume Catch Crop Serradella on Subsequent Growth and P Mobilization under Barley in Different Fertilization Treatments

by Nora Vitow, Theresa Zicker, Akane Chiba, Anika Zacher, Bettina Eichler-Löbermann, Stefanie Schulz, Michael Schloter, Christel Baum and Peter Leinweber

Agronomy 2021, 11(12), 2437; https://doi.org/10.3390/agronomy11122437 - 29 Nov 2021

Cited by 4 | Viewed by 1823

Abstract

Legume catch crops can enhance soil fertility and promote the N and P supply of the subsequent main crop, especially with low mineral fertilizer use. However, the specific impact of catch crops on arbuscular mycorrhiza formation of the following main crop is unknown. [...] Read more.

Legume catch crops can enhance soil fertility and promote the N and P supply of the subsequent main crop, especially with low mineral fertilizer use. However, the specific impact of catch crops on arbuscular mycorrhiza formation of the following main crop is unknown. Therefore, the impact of serradella (Ornithopus sativus) vs. bare fallow was tested on mycorrhiza formation, potential soil enzyme activities and plant-available P under subsequently grown barley (Hordeum vulgare) and different fertilization treatments (P-unfertilized—P0; triple superphosphate—TSP; compost—COM; combined—COM + TSP) in a long-term field experiment in northeastern Germany. Catch cropping significantly increased mycorrhiza formation of barley up to 14% compared to bare fallow. The impact of serradella on mycorrhiza formation exceeded that of the fertilization treatment. Serradella led to increased phosphodiesterase activities and decreased ß-glucosidase activities in soil. Plant availability of P was not significantly affected by serradella. These findings provide initial evidence that even serradella as a non-host crop of mycorrhizal fungi can promote the mycorrhiza formation of the subsequent crop and P mobilization in soil. We conclude that the prolonged vegetation cover of arable soils by the use of catch crops can promote P mobilization and transfer from P pools to the following main crops. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 2055 KiB

Open AccessArticle

Replacing Synthetic Nitrogen Fertilizer with Different Types of Organic Materials Improves Grain Yield in China: A Meta-Analysis

by Xiaoru Fan, Zekai Chen, Zihan Niu, Ruiyao Zeng, Jingmin Ou, Xingxing Liu and Xiaolong Wang

Agronomy 2021, 11(12), 2429; https://doi.org/10.3390/agronomy11122429 - 28 Nov 2021

Cited by 9 | Viewed by 3049

Abstract

Synthetic nitrogen fertilizer substitution (NSS) with different types of organic material is a cleaner agricultural practice for reducing the application of synthetic N input in farmlands while also relieving the environmental issues caused by the discharge of organic wastes. However, the effects of [...] Read more.

Synthetic nitrogen fertilizer substitution (NSS) with different types of organic material is a cleaner agricultural practice for reducing the application of synthetic N input in farmlands while also relieving the environmental issues caused by the discharge of organic wastes. However, the effects of the NSS practice on crop yields, being the primary objective of agricultural activity, is still uncertain in China. This study conducted a meta-analysis to assess the impacts of the NSS practices with different types of organic materials on crop yields. Results showed that the average crop yield was increased by 3.4%, with significant differences under NSS, thereby demonstrating that this practice contributed to improving crop yields, especially of rice and maize. According to published reports, the NSS practices involving chicken manure, pig manure, and crop straw increased crop yields by 4.79, 7.68, and 3.28%, respectively, with significant differences, thus demonstrating the superior effects needed for replacing synthetic N fertilizer. Moreover, substitution ratios (SR) between 0% and 60% could be suggested when using the NSS practice, with the high SR recommended when the original soil fertility was adequate for crops. Considering the long-term effects of applied organic materials, improving the grain yield with the NSS practice should be expected in the long-term. By effectively applying the NSS, this study attempted to scientifically decide on the type of organic materials and the appropriate SR based on the conditions of the soil and the crop. The results provide research information for the development of clean agricultural production and food security in China. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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23 pages, 1520 KiB

Open AccessArticle

Efficiency of Rice Husk Biochar with Poultry Litter Co-Composts in Oxisols for Improving Soil Physico-Chemical Properties and Enhancing Maize Performance

by Hamed Ahmed Alarefee, Che Fauziah Ishak, Daljit Singh Karam and Radziah Othman

Agronomy 2021, 11(12), 2409; https://doi.org/10.3390/agronomy11122409 - 26 Nov 2021

Cited by 3 | Viewed by 2504

Abstract

Efficient use of co-composted organic manure with biochar is one of the sustainable management practices in an agriculture system to increase soil fertility and crop yield. The objectives of this research are to evaluate the use of co-composted biochar, biochar in formulation with [...] Read more.

Efficient use of co-composted organic manure with biochar is one of the sustainable management practices in an agriculture system to increase soil fertility and crop yield. The objectives of this research are to evaluate the use of co-composted biochar, biochar in formulation with poultry litter (PL), and PL compost on soil properties and maize growth. Organic amendments were applied at 10 Mg ha⁻¹, and synthetic fertilizer was applied at the recommended rate of maize (N: P₂O₅: K₂O at 60:60:40 kg ha⁻¹). The results showed that addition of organic amendment significantly increased the total biomass parameter compared to the control, which ranged from 23.2% to 988.5%. The pure biochar treatment yielded lower biomass than the control by 27.1%, which was attributed to its low nutrient content. Consequently, the application of the co-composted biochar achieved higher plant height and aerial portion, which ranged from 46.86% to 25.74% and 7.8% to 108.2%, respectively, in comparison to the recommended fertilizer rate. In addition, the soil amended with co-composted biochar had a significant increase in soil organic matter and had significantly higher chlorophyll and nutrient concentrations in plants, which increased with an increase in the biochar ratio of the co-composts. This was probably attributed to the release of the nutrients retained during composting, thereby possibly making the co-composted biochar act as a slow-release fertilizer. In conclusion, the addition of organic manure with biochar enhanced the nutrient supply by gradual release in comparison to the mineral fertilizer. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1627 KiB

Open AccessArticle

Negative Pressure Irrigation System Reduces Soil Nitrogen Loss for Lettuce during Greenhouse Production

by Xiang Gao, Shuxiang Zhang, Yanyan Song and Huaiyu Long

Agronomy 2021, 11(12), 2380; https://doi.org/10.3390/agronomy11122380 - 24 Nov 2021

Cited by 4 | Viewed by 2215

Abstract

Negative pressure irrigation (NPI) to grow crops reduces the application of fertilizer and water while also promoting yield and quality. However, plantation vegetables usually require a large input of nitrogen (N) fertilizer in a greenhouse setting, which will lower the soil quality and [...] Read more.

Negative pressure irrigation (NPI) to grow crops reduces the application of fertilizer and water while also promoting yield and quality. However, plantation vegetables usually require a large input of nitrogen (N) fertilizer in a greenhouse setting, which will lower the soil quality and accelerate the emission of greenhouse gases. Therefore, the purpose of this research was to explore planting lettuce under an NPI system that retrenches N fertilizer application and mitigates N₂O emissions compared with conventional irrigation (CI). This research proved that under NPI conditions, nitrate and ammonium fluctuated slightly in the soil, stabilizing in the range of 18–28 mg kg⁻¹, while that of CI was 20–55 mg kg⁻¹. The NPI alleviated N₂O emissions, and NPI-N150 and NPI-N105 decreased them by 18% and 32%, respectively, compared with those for CI-N150. The main explanation was that the NPI inhibited the formation of NO₃⁻-N, reduced the copies number of AOA and AOB as well as the abundance of Nitrospira in the soil, and weakened the soil nitrate reductase and urease activities. The results of this research provide a reliable scientific method for reducing the use of water and N fertilizer while cultivating lettuce, as well as for reducing N₂O emissions from agricultural facilities. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 3237 KiB

Open AccessArticle

Fertilization Regulates Accumulation and Allocation of Biomass and Nutrients in Phoebe bournei Seedlings

by Zhi-Jian Yang, Xiao-Hui Wu, Lai-He Chen, Lan-Ming Huang, Yu Chen, Juan Wu, Yousry A. El-Kassaby, Steven C. Grossnickle and Jin-Ling Feng

Agriculture 2021, 11(12), 1187; https://doi.org/10.3390/agriculture11121187 - 24 Nov 2021

Cited by 6 | Viewed by 2749

Abstract

To study the effect of N-P-K fertilization on Phoebe bournei seedlings’ organs dry biomass, and nutrients accumulation and allocation, and to further uncover how nutrients regulating dry biomass formation through fertilization, we utilized the “3414” experiment design. The results showed that N, P, [...] Read more.

To study the effect of N-P-K fertilization on Phoebe bournei seedlings’ organs dry biomass, and nutrients accumulation and allocation, and to further uncover how nutrients regulating dry biomass formation through fertilization, we utilized the “3414” experiment design. The results showed that N, P, and K fertilizer promoted dry biomass accumulation, and root, stem, and total plant N, P, and K content and accumulation in seedlings. The dry biomass accumulations of root, stem, and total plant increased first and then decreased with the increase of N, P, and K application rates, which was basically consistent with the change in dry biomass allocations and N, P, and K contents, accumulations, and allocations. Root N accumulation, root P accumulation, and total plant K accumulation were the key indicators for seedlings growth. N fertilizer had the greatest effect on total dry biomass and root N accumulation, was the most important fertilizer for the growth of Phoebe bournei seedlings, can regulate the growth of root and leaves, is beneficial to root growth at medium-low N fertilizer levels (N: 0.266–0.532 g·plant⁻¹), and leaves growth at high N fertilizer level (N: 0.798 g·plant⁻¹). P fertilizer rate can regulate the seedling stem growth, reaching the maximum at the medium level P application (P₂O₅: 0.1332 g·plant⁻¹). K fertilizer had the greatest effect on the root P accumulation and total K accumulation, promoting K transport from leaves to root, improved root and stem growth, and inhibited leaves growth. The N, P, and K fertilizer three-factor application can better promote nutrient uptake than double-factor and single-factor fertilization, with highest dry biomass accumulation at the medium level of N, P, K fertilizer (N: 0.532 g·plant⁻¹; P₂O₅: 0.1232 g·plant⁻¹; K₂O: 0.356 g·plant⁻¹). In conclusion, N, P, and K fertilization promoted the N, P, and K absorption, increased root, stem, and leaves N, P, and K content and accumulation, and promoted the seedling dry biomass accumulation, but reversed under excessive application of N, P, and K fertilizer; and N fertilizer was beneficial to root and leaves growth, P fertilizer to stem growth, and K fertilizer to material transfer, which provided a theoretical basis for robust Phoebe bournei seedling cultivation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 2574 KiB

Open AccessArticle

Gram-Negative Bacteria from Organic and Conventional Agriculture in the Hydrographic Basin of Loja: Quality or Pathogen Reservoir?

by Darío Cruz, Rodrigo Cisneros, Ángel Benítez, Wilson Zúñiga-Sarango, Jhoan Peña, Heriberto Fernández and Andrea Jaramillo

Agronomy 2021, 11(11), 2362; https://doi.org/10.3390/agronomy11112362 - 22 Nov 2021

Cited by 5 | Viewed by 4932

Abstract

Organic and conventional agriculture are vital for the development of human society; however, the use of contaminated water and the inappropriate use of organic chemical fertilizers can lead to an increase in the microbial load (potentially pathogenic) of the normal microbiota of the [...] Read more.

Organic and conventional agriculture are vital for the development of human society; however, the use of contaminated water and the inappropriate use of organic chemical fertilizers can lead to an increase in the microbial load (potentially pathogenic) of the normal microbiota of the agricultural soil. In this context, the aim of our study was to isolate Gram-negative bacteria from the superficial soil layer and irrigation water of agricultural areas (11 organic farms and nine conventional farms) and consider their potential ecological and health risk importance. Through culture isolation using three bacterial media (TSA) trypticase soy agar (general nutritive media); MacConkey Gram-negative bacteria and (EMB) eosin methylene blue agar (selective for Enterobacteriaceae) and classical biochemical tests, we recorded a total of 12 bacterial species, most belonging to the Enterobacteriaceae family, such as Enterobacter, Escherichia, Klebsiella, Salmonella and Shigella, which can be pathogenic for humans and animals. In contrast, bacteria such as Pantoea agglomerans, Pseudomonas aeruginosa, P. fluorescens and Burkholderia mallei could facultatively work as diazotrophic or plant growth-promoting rhizobacteria. Soil bacteria richness detected with the media applied was significantly higher than water bacteria, but we found no significant differences between organic and conventional agriculture. We conclude that the isolated bacteria in water and soil mostly belongs to enteropathogenic bacteria which could be pathogenic to animals and humans. While other bacteria like Pseudomonas aeruginosa could be viewed as useful by improving nutrient availability in agricultural soil. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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21 pages, 911 KiB

Open AccessEditor’s ChoiceReview

A Review: Soil Management, Sustainable Strategies and Approaches to Improve the Quality of Modern Viticulture

by Eleonora Cataldo, Maddalena Fucile and Giovan Battista Mattii

Agronomy 2021, 11(11), 2359; https://doi.org/10.3390/agronomy11112359 - 21 Nov 2021

Cited by 33 | Viewed by 6632

Abstract

Conservative and sustainable soil management in vineyards is an approach of primary importance not only for the yield (tons per hectare) and grapes’ quality (primary and secondary metabolites), but also for the greater preservation of the ecosystem. Compared to sustained-conventional tillage and perpetual [...] Read more.

Conservative and sustainable soil management in vineyards is an approach of primary importance not only for the yield (tons per hectare) and grapes’ quality (primary and secondary metabolites), but also for the greater preservation of the ecosystem. Compared to sustained-conventional tillage and perpetual applications of fertilizers and phytopharmaceutical, these techniques give a primary role for safeguarding biodiversity, conserving soil fertility, and keeping vegetative–productive balance. The soil and, consequently, the wine production are in fact an intimate ecosystem jeopardized not only by a reckless approach by man (technical input, such as pesticides, fuel, fertilizers, and herbicides, are estimated to be responsible for 24% of anthropogenic greenhouse gases emissions), but also by climate change, as rising summer temperatures and reduced precipitation leads to production declines and water shortages in the soil. In fact, there are several risks associated with unbalanced soil management, such as compaction, pollution, soil erosion, soil organic matter (SOM) depletion, and loss of biodiversity, that lead to a drop in grape quality and quantity. In this context, soil management in viticulture and sustainable strategies assume greater significance to improve the quality of modern viticulture. This review aims to highlight new agronomic techniques capable of enhancing the resilience of the system and contributing to conservation and ecosystem services provision, especially as wine consumers increasingly appreciate environmentally friendly farming practices. In particular, the review aims to focus the positive implications and repercussions as a result of these practices (e.g., compost, vermicompost, biochar, Ascophyllum nodosum, Arbuscular mycorrhizal fungi (AMF), Trichoderma, zeolite, partial root drying, cover cropping, and mulching). Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1357 KiB

Open AccessArticle

The Effect of Microbial Inoculation under Various Nitrogen Regimes on the Uptake of Nutrients by Apple Trees

by Kamila Łucja Bokszczanin, Dariusz Wrona and Sebastian Przybyłko

Agronomy 2021, 11(11), 2348; https://doi.org/10.3390/agronomy11112348 - 19 Nov 2021

Cited by 6 | Viewed by 2163

Abstract

The European Green Deal strategy currently implemented in the EU aims to, among others, reduce the negative impact of fertilization on the environment. One of the solutions influencing the nutritional status of plants and the improvement of soil quality is the use of [...] Read more.

The European Green Deal strategy currently implemented in the EU aims to, among others, reduce the negative impact of fertilization on the environment. One of the solutions influencing the nutritional status of plants and the improvement of soil quality is the use of plant symbiosis with microorganisms. Thus, in this study we investigated the effect of arbuscular mycorrhizal fungi (AMFs) and plant-growth-promoting rhizobacteria (PGPR) colonization on the nutritional status of apple leaves and fruit, depending on the nitrogen treatment. In a fully factorial experiment, trees were grown for nine years with or without AMFs and PGPR. We compared several ammonium nitrate treatments as well as growth without fertilization as a control. The interactions between inoculation and doses of nitrogen fertilization were observed. AMF + PGPR significantly increased the concentration of nitrogen (N), phosphorus (P), and potassium (K) in leaves up to 5%, 23%, and 19%, respectively, depending on the N dosage. Conversely, in uninoculated trees, the nitrogen treatment had a negative impact on the leaf P mineral status. On the other hand, under microbial inoculation conditions, the dose of 100 kg N∙ha⁻¹ diminished the leaf phosphorus content in comparison to other N doses, by a maximum of 9.6%. AMF + PGPR, depending on the N treatment, either did not influence or it decreased the Mg and Ca concentrations in the leaves by maximums of 8% and 15%, respectively. Microbial inoculation had no effect on the acquisition of Ca and Mg by fruits, except for the coupled negative influence of the 100 kg N∙ha⁻¹ treatment. Symbiosis positively conditioned the K in fruits under a specific N regime—100 kg N∙ha⁻¹ divided into two applications during the season and 50 kg N∙ha⁻¹ applied to the herbicide strip, increasing the concentration by approximately 4% and 8%, respectively. This study greatly contributes to our understanding of the benefits of AMF and PGPR on perennials and encourages the future exploration of their effects on apple yield and fruit quality. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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9 pages, 1237 KiB

Open AccessCommunication

Arbuscular Mycorrhizal Communities in the Roots of Sago Palm in Mineral and Shallow Peat Soils

by Koki Asano, Willy Vincent Anak Kagong, Siraj Munir Bin Mohammad, Kurumi Sakazaki, Muhamad Syukrie Abu Talip, Siti Sahmsiah Sahmat, Margaret Kit Yok Chan, Toshiyuki Isoi, Mana Kano-Nakata and Hiroshi Ehara

Agriculture 2021, 11(11), 1161; https://doi.org/10.3390/agriculture11111161 - 18 Nov 2021

Cited by 4 | Viewed by 2675

Abstract

Communities of arbuscular mycorrhizal fungi (AMF) in plant roots improve host plant growth. In this study, AMF communities in the roots of the sago palm (Metroxylon sagu Rottb.) were investigated in mineral soil (MS) and shallow peat soil (SPS) in Sarawak, Malaysia. [...] Read more.

Communities of arbuscular mycorrhizal fungi (AMF) in plant roots improve host plant growth. In this study, AMF communities in the roots of the sago palm (Metroxylon sagu Rottb.) were investigated in mineral soil (MS) and shallow peat soil (SPS) in Sarawak, Malaysia. MS exhibited lower moisture content (MS, 38.1; SPS, 79.8%), higher pH (H₂O) (MS, 4.6; SPS, 4.1), higher soil bulk density (MS, 1.03; SPS, 0.20 g cm⁻³), and higher nitrogen content (MS, 16.9; SPS, 2.7 kg m⁻³) than SPS at the same soil depth, while the phosphorus (P) content (Bray II) (MS, 1.6; SPS, 1.9 g P₂O₅ m⁻³) was similar. The AMF colonization rate was significantly lower in SPS (39.2 ± 12.5%) than in MS (73.2 ± 4.6%). The higher number of AMF operational taxonomic units (OTUs) was detected by amplicon sequencing of the partial small-subunit rRNA gene (MS, 78; SPS, 50). A neighbor-joining tree of obtained OTUs revealed that they belonged to Acaulosporaceae, Ambisporaceae, Claroideoglomeraceae, Gigasporaceae, and Glomeraceae. The lower abundance and diversity of AMF in SPS are possibly caused by abiotic factors, including soil physicochemical properties. Glomus and Acaulospora species detected in SPS might have strong tolerance against acidity and high soil moisture content. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 14047 KiB

Open AccessArticle

Microalgae and Biochar Agro-Fertilization of the Palestinian Rehan Barley Cultivar under Salinity Stress

by Ashwaq A. Najjar, Arnd J. Kuhn, Sharaf M. Al-Tardeh and Christina M. Kuchendorf

Agronomy 2021, 11(11), 2309; https://doi.org/10.3390/agronomy11112309 - 15 Nov 2021

Cited by 5 | Viewed by 2888

Abstract

The efficient transfer of nutrients to plants in the form of biofertilizers on poor substrate was investigated. Biochar and dried algae biomass as well as mineral fertilizer were used to test the growth of the Palestinian ‘Rehan’ barley cultivar under salinity stress (4, [...] Read more.

The efficient transfer of nutrients to plants in the form of biofertilizers on poor substrate was investigated. Biochar and dried algae biomass as well as mineral fertilizer were used to test the growth of the Palestinian ‘Rehan’ barley cultivar under salinity stress (4, 8, and 16 mS/cm EC). Rehan cultivar showed resilience to moderate levels of salinity and could still grow under high salinity stress (16 mS/cm EC). Rehan barley possessed better growth at early growth stage under the applied biofertilizers such as dried freshwater algal biomass (Chlorella vulgaris) and nutrient-laden biochar. It showed better growth than wheat (ssp. scirocco) under the same conditions. Its growth was highly improved by biochar treatment in low and moderate salinity conditions. Moreover, the combined effect between biochar and dried algae biomass could improve Rehan barley growth, but less than the effect of each biofertilizer separately. The biofertilizers affected most plant growth parameters under the salinity level of 4 and 8 mS/cm EC positively, while the growth declined again at 16 mS/cm EC. Overall, the biochar treatment showed the same effect as the mineral fertilizer on most of the parameters. The dried algae biomass and biochar also affected soil conditions. The highest soil water content (15.09%) was found in algae biomass treatments with 16 mS/cm EC. Biochar with 8 and 16 mS/cm EC had the highest pH value (8.63) near the rhizospheres. The nitrogen level was highest in the bottom soil sample (0.28 g N/kg soil) for biochar with 0 and 4 mS/cm EC. Meanwhile, the phosphate concentration was the highest (3.3 mg PO₃⁻²/kg soil) in algae fertilizer treatments with 0 mS/cm EC in the bottom soil sample and lowest (4.14 mg PO₃⁻²/kg soil) for the biochar with 8 mS/cm EC. The dried algae biomass and the biochar treatments can subsequently be viewed as conditioner substrates for improving the quality and fertility of the soil. Where possible, they should be considered as complement or replacement of mineral and manure fertilization to improve the impact on soil and environment. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 275 KiB

Open AccessArticle

The Effect of Meat and Bone Meal (MBM) on Crop Yields, Nitrogen Content and Uptake, and Soil Mineral Nitrogen Balance

by Anna Nogalska and Aleksandra Załuszniewska

Agronomy 2021, 11(11), 2307; https://doi.org/10.3390/agronomy11112307 - 15 Nov 2021

Cited by 9 | Viewed by 3905

Abstract

A long-term (six year) field experiment was conducted in Poland to evaluate the effect of meat and bone meal (MBM), applied without or with mineral nitrogen (N) fertilizer, on crop yields, N content and uptake by plants, and soil mineral N balance. Five [...] Read more.

A long-term (six year) field experiment was conducted in Poland to evaluate the effect of meat and bone meal (MBM), applied without or with mineral nitrogen (N) fertilizer, on crop yields, N content and uptake by plants, and soil mineral N balance. Five treatments were compared: MBM applied at 1.0, 1.5, and 2.0 Mg ha⁻¹, inorganic NPK, and zero-fert check. Mineral N accounted for 100% of the total N rate (158 kg ha⁻¹) in the NPK treatment and 50%, 25%, and 0% in MBM treatments. The yield of silage maize supplied with MBM was comparable with that of plants fertilized with NPK at 74 Mg ha⁻¹ herbage (30% DM) over two years on average. The yields of winter wheat and winter oilseed rape were highest in the NPK treatment (8.9 Mg ha⁻¹ grain and 3.14 Mg ha⁻¹ seeds on average). The addition of 25% and 50% of mineral N to MBM had no influence on the yields of the tested crops. The N content of plants fertilized with MBM was satisfactory (higher than in the zero-fert treatment), and considerable differences were found between years of the study within crop species. Soil mineral N content was determined by N uptake by plants rather than the proportion of mineral N in the total N rate. Nitrogen utilization by plants was highest in the NPK treatment (58%) and in the treatment where mineral N accounted for 50% of the total N rate (48%). Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

24 pages, 5430 KiB

Open AccessArticle

Using a Hybrid Neural Network Model DCNN–LSTM for Image-Based Nitrogen Nutrition Diagnosis in Muskmelon

by Liying Chang, Daren Li, Muhammad Khalid Hameed, Yilu Yin, Danfeng Huang and Qingliang Niu

Horticulturae 2021, 7(11), 489; https://doi.org/10.3390/horticulturae7110489 - 12 Nov 2021

Cited by 8 | Viewed by 3486

Abstract

In precision agriculture, the nitrogen level is significantly important for establishing phenotype, quality and yield of crops. It cannot be achieved in the future without appropriate nitrogen fertilizer application. Moreover, a convenient and real-time advance technology for nitrogen nutrition diagnosis of crops is [...] Read more.

In precision agriculture, the nitrogen level is significantly important for establishing phenotype, quality and yield of crops. It cannot be achieved in the future without appropriate nitrogen fertilizer application. Moreover, a convenient and real-time advance technology for nitrogen nutrition diagnosis of crops is a prerequisite for an efficient and reasonable nitrogen-fertilizer management system. With the development of research on plant phenotype and artificial intelligence technology in agriculture, deep learning has demonstrated a great potential in agriculture for recognizing nondestructive nitrogen nutrition diagnosis in plants by automation and high throughput at a low cost. To build a nitrogen nutrient-diagnosis model, muskmelons were cultivated under different nitrogen levels in a greenhouse. The digital images of canopy leaves and the environmental factors (light and temperature) during the growth period of muskmelons were tracked and analyzed. The nitrogen concentrations of the plants were measured, we successfully constructed and trained machine-learning- and deep-learning models based on the traditional backpropagation neural network (BPNN), the emerging convolution neural network (CNN), the deep convolution neural network (DCNN) and the long short-term memory (LSTM) for the nitrogen nutrition diagnosis of muskmelon. The adjusted determination coefficient (R²) and mean square error (MSE) between the predicted values and measured values of nitrogen concentration were adopted to evaluate the models’ accuracy. The values were R² = 0.567 and MSE = 0.429 for BPNN model; R² = 0.376 and MSE = 0.628 for CNN model; R² = 0.686 and MSE = 0.355 for deep convolution neural network (DCNN) model; and R² = 0.904 and MSE = 0.123 for the hybrid model DCNN–LSTM. Therefore, DCNN–LSTM shows the highest accuracy in predicting the nitrogen content of muskmelon. Our findings highlight a base for achieving a convenient, precise and intelligent diagnosis of nitrogen nutrition in muskmelon. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 620 KiB

Open AccessArticle

Estimation of Diagnosis and Recommendation Integrated System (DRIS), Compositional Nutrient Diagnosis (CND) and Range of Normality (RN) Norms for Mineral Diagnosis of Almonds Trees in Spain

by Mario Ferrández-Cámara, Juan José Martínez-Nicolás, Marina Alfosea-Simón, José María Cámara-Zapata, Pablo Melgarejo Moreno and Francisco García-Sánchez

Horticulturae 2021, 7(11), 481; https://doi.org/10.3390/horticulturae7110481 - 10 Nov 2021

Cited by 7 | Viewed by 2706

Abstract

To ensure good fertilization, it is necessary to know the optimum nutrient levels for each crop. The most common method for obtaining this information for almond trees is to perform a foliar analysis coupled with the use of interpretive tools such as the [...] Read more.

To ensure good fertilization, it is necessary to know the optimum nutrient levels for each crop. The most common method for obtaining this information for almond trees is to perform a foliar analysis coupled with the use of interpretive tools such as the traditional range of normality. However, currently, there are other, more sophisticated methods such as the DRIS (Diagnosis and Recommendation Integrated System) and the CND (Compositional Nutrient Diagnosis) which take into account the relationship between nutrients. However, little information is available with respect to these methods in the case of almond trees. In the present work, 288 samples of three contrasting varieties of almond were analyzed—Ferraduel, Ferragnes, and Garrigues (Prunus dulcis, Mill.)—corresponding to bi-weekly sampling between the months of May and September. Leaf analysis data, run with different mathematical and statistical models, lead to knowledge of the optimum period for harvesting samples and the determination of the ranges of normality and norms of DRIS and CND for the Ferraduel, Ferragnes, and Garrigues varieties. Data gained from the leaf nutrient content reported that the best season to harvest and interpret leaf samples was July. In addition, Ferraduel and Ferragnes had higher N, P, and K (2.22, 0.14, and 1.04 mg Kg⁻¹ dw, respectively) than Garrigues (2.00, 0.09. 0.67 mg Kg⁻¹ dw). The norms obtained with the leaf mineral data showed similar values between the Ferraduel and Ferragnes varieties but different values for Garrigues variety. Therefore, Garriges had the highest N/P, N/K, P/K, and P × Mg norms in the DRIS method and the highest V_N and V_Ca norms in the CND method. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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22 pages, 3830 KiB

Open AccessArticle

Soil Microbial and Nematode Community Response to the Field Application of Recycled Bio-Based Fertilisers in Irish Grassland

by Anna Karpinska, Demi Ryan, Kieran Germaine, David Dowling, Patrick Forrestal and Thomais Kakouli-Duarte

Sustainability 2021, 13(22), 12342; https://doi.org/10.3390/su132212342 - 09 Nov 2021

Cited by 8 | Viewed by 2693

Abstract

Phosphorus (P) is an essential plant nutrient routinely applied to soils as an agricultural fertiliser, frequently in non-renewable, inorganic forms. Finite reserves and growing demand for agricultural phosphorus mean alternative P resources need to be explored. Recycling-derived fertilisers (RDF) recovered from specific waste [...] Read more.

Phosphorus (P) is an essential plant nutrient routinely applied to soils as an agricultural fertiliser, frequently in non-renewable, inorganic forms. Finite reserves and growing demand for agricultural phosphorus mean alternative P resources need to be explored. Recycling-derived fertilisers (RDF) recovered from specific waste streams, using nutrient recovery technologies, have the potential to replace conventional phosphorus fertilisers used in agriculture. Healthy functioning soil microbial and nematode communities are essential players in maintaining soil health and nutrient status. Thus, it is important to assess the responses of these communities to RDF application. We compared soil microbial and nematode communities of conventional fertiliser and RDF treated soil, in the form of struvite and ash, using next-generation sequencing (NGS) technologies in a phosphate-fertiliser replacement value (P-FRV) field trial. Bacterial and nematode communities displayed significant changes under the different P fertilisation treatments, while fungal communities were relatively unaffected. Bacterial diversity was higher among RDF treatments than conventional treatments, while nematode diversity was reduced by one ash treatment. Available potassium and phosphate were the main drivers of bacterial community changes when analysed by canonical correspondence analysis (CCA), while available phosphate alone was the driver of nematode community shifts. Of the RDF, struvite products yielded the highest crop biomass, maintained microbial diversity and were associated with the least disturbed nematode communities. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2323 KiB

Open AccessArticle

Effect of Aqueous Neem Leaf Extracts in Controlling Fusarium Wilt, Soil Physicochemical Properties and Growth Performance of Banana (Musa spp.)

by Ung Yi, Sakimin Siti Zaharah, Siti Izera Ismail and Mohamed Hanafi Musa

Sustainability 2021, 13(22), 12335; https://doi.org/10.3390/su132212335 - 09 Nov 2021

Cited by 2 | Viewed by 3848

Abstract

Neem leaf extracts (NLEs) have frequently been used to inhibit plant diseases and for the development of bio-fertilizer, leading to the commercial exploitation of this tree. However, previous studies have indicated contradictory outcomes when NLE was used as an antifungal disease treatment and [...] Read more.

Neem leaf extracts (NLEs) have frequently been used to inhibit plant diseases and for the development of bio-fertilizer, leading to the commercial exploitation of this tree. However, previous studies have indicated contradictory outcomes when NLE was used as an antifungal disease treatment and bio-fertilizer applied through the soil on several crops, including banana. Therefore, the present investigation was undertaken to examine the physicochemical properties of soil, the growth performance of crops, and the severity of diseases caused by Fusarium oxysporum (Foc) on Cavendish bananas treated with aqueous NLE. Banana plants associated with the fungus were significantly affected by high disease severity and symptoms index (external leaves and internal rhizome), a high infection percentage of Fusarium wilt (%), dropping off of leaves as well as rotting of the root. Meanwhile, it was observed that the application of extract significantly improved the crop height, stem diameter, root size and distribution (root surface area, root diameter, and root volume), root–shoot ratio, as well as the soil physicochemical properties (CEC, N, p, K, Ca, and Mg), which enhanced resistance to Fusarium wilt diseases. We conclude that the application of NLE solution promotes better growth of Cavendish banana plants, soil physicochemical properties, and resistance to Fusarium wilt infection. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 978 KiB

Open AccessEditor’s ChoiceArticle

Biochar Reduces the Adverse Effect of Saline Water on Soil Properties and Wheat Production Profitability

by Mohamed E. A. El-sayed, Mohamed Hazman, Ayman Gamal Abd El-Rady, Lal Almas, Mike McFarland, Ali Shams El Din and Steve Burian

Agriculture 2021, 11(11), 1112; https://doi.org/10.3390/agriculture11111112 - 09 Nov 2021

Cited by 13 | Viewed by 2460

Abstract

The goal of this study is to assess the use of saline groundwater in combination with soil amendments to increase the efficiency of wheat production in new agricultural soil in Egypt. The experiment was conducted during the two consecutive growing seasons, 2019/2020 and [...] Read more.

The goal of this study is to assess the use of saline groundwater in combination with soil amendments to increase the efficiency of wheat production in new agricultural soil in Egypt. The experiment was conducted during the two consecutive growing seasons, 2019/2020 and 2020/2021, at the Shandaweel Agricultural Research Station, Sohag, Egypt. In this study, plants of Shandaweel 1 spring bread wheat cultivar were grown under the combinations of the two water treatments, i.e., freshwater (307.2 ppm) and saline water (3000 ppm (NaCl + MgCl₂)) representing groundwater in Egypt delivered by drip irrigation and the two biochar rates, i.e., zero and 4.8 ton/ha as a soil amendment. The cob corn biochar (CCB) was synthesized by using the slow pyrolysis process (one hour at 350 °C). The results revealed that saline water reduced the grain yield ratio by 8.5%, 11.0%, and 9.7% compared to non-saline water during seasons 2019/2020 and 2020/2021 and over seasons, respectively. Concerning, combined over seasons, the biochar addition enhanced the grain yield by 5.6% and 13.8% compared to non-biochar addition under fresh and saline irrigation water conditions, respectively. Thus, the results indicated and led to a preliminary recommendation that saline groundwater is a viable source of irrigation water and that biochar seemed to alleviate salinity stress on wheat production and in reclaimed soils of Egypt. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1633 KiB

Open AccessArticle

Short-Term Decomposition and Nutrient-Supplying Ability of Sewage Sludge Digestate, Digestate Compost, and Vermicompost on Acidic Sandy and Calcareous Loamy Soils

by Nikolett Uzinger, Orsolya Szécsy, Nóra Szűcs-Vásárhelyi, István Padra, Dániel Benjámin Sándor, Zdenko Lončarić, Eszter Draskovits and Márk Rékási

Agronomy 2021, 11(11), 2249; https://doi.org/10.3390/agronomy11112249 - 06 Nov 2021

Cited by 2 | Viewed by 2046

Abstract

Organic waste and the compost and vermicompost derived from it may have different agronomic values, but little work is available on this aspect of sewage sludge. A 75-day pot experiment with perennial ryegrass (Lolium perenne) as the test plant aimed to [...] Read more.

Organic waste and the compost and vermicompost derived from it may have different agronomic values, but little work is available on this aspect of sewage sludge. A 75-day pot experiment with perennial ryegrass (Lolium perenne) as the test plant aimed to investigate the fertiliser value and organic matter replenishment capacity of digested sewage sludge (DS) and the compost (COM) and vermicompost (VC) made from it, applied in 1% and 3% doses on acidic sand and calcareous loam. The NPK content and availability, changes in organic carbon content and plant biomass, and the efficiency of the amendments as nitrogen fertilisers were investigated. The final average residual carbon content for DS, COM, and VC was 35 ± 34, 85 ± 46, and 55 ± 46%, respectively. The organic carbon mineralisation rate depended on the soil type. The additives induced significant N mineralisation in both soils: the average increment in mineral N content was 1.7 times the total added N on acidic sand and 4.2 times it on calcareous loam for the 1% dose. The agronomic efficiency of COM and VC as fertilisers was lower than that of DS. In the short term, DS proved to be the best fertiliser, while COM was the best for organic matter replenishment. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2152 KiB

Open AccessEditor’s ChoiceArticle

Genotype by Trait Interaction (GT) in Maize Hybrids on Complete Fertilizer

by Seyed Mohammad Nasir Mousavi, Csaba Bojtor, Árpád Illés and János Nagy

Plants 2021, 10(11), 2388; https://doi.org/10.3390/plants10112388 - 05 Nov 2021

Cited by 16 | Viewed by 2145

Abstract

We investigated the interaction between genotype by trait, and an experiment was conducted at the University of Debrecen. Two maize cultivars, FAO340 and FAO410, were studied in a randomized complete block design with four replications. This experiment was applied to the six fertilization [...] Read more.

We investigated the interaction between genotype by trait, and an experiment was conducted at the University of Debrecen. Two maize cultivars, FAO340 and FAO410, were studied in a randomized complete block design with four replications. This experiment was applied to the six fertilization treatments. Fertilizer levels were NPK0 (control) (N:0, P2O5:0, K2O:0), NPK1 (N:30, P2O5:23, K2O:27), NPK2 (N:60, P2O5:46, K2O:54), NPK3 (N:90, P2O5:69, K2O:81), NPK4 (N:120, P2O5:92, K2O:108), and NPK5 (N:150, P2O5:115, K2O:135). The first principal component showed 54.24%, and the second principal component showed 20.75%, which explained the total squares interaction using the AMMI model in the case of the FAO410 hybrid. As regards the FAO340 hybrid, the first principal component showed 58.18%, and the second principal component showed 18.04%, explaining the total squares interaction using the AMMI model in the FAO410 hybrid. In the GGE biplot on FAO410, the first and the second principal components covered 91.20% of the total data in this analysis. Accordingly, the desirable treatment was NPK5, followed by NPK4, NPK2, NPK3, NPK1, and NPK0. NPK4 and NPK5 had the most desirable treatments for the number of seeds per row, chlorophyll, weight of 1000 seeds, and stem diameter in the case of the FAO410 hybrid. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2890 KiB

Open AccessArticle

Isolation of Pseudomonas Strains with Potential for Protection of Soybean Plants against Saline Stress

by Stefanie Bernardette Costa-Gutierrez, María Carolina del Valle Caram-Di Santo, Ana María Zenoff, Manuel Espinosa-Urgel, Ricardo Ezequiel de Cristóbal and Paula Andrea Vincent

Agronomy 2021, 11(11), 2236; https://doi.org/10.3390/agronomy11112236 - 04 Nov 2021

Cited by 5 | Viewed by 2325

Abstract

Salinity is a major detrimental factor for plant growth and crop productivity that could be alleviated by the use of plant growth promoting bacteria (PGPB) with a protective role in such stressful conditions. In this study, four native strains of the genus Pseudomonas [...] Read more.

Salinity is a major detrimental factor for plant growth and crop productivity that could be alleviated by the use of plant growth promoting bacteria (PGPB) with a protective role in such stressful conditions. In this study, four native strains of the genus Pseudomonas were isolated from both a strongly saline soil and the rhizosphere of soybean plants grown in a slightly saline soil. These isolates were able to tolerate high NaCl concentration, showed efficient adhesion to biotic and abiotic surfaces and efficiently colonized the rhizosphere of soybean grown in slightly saline soil. In these conditions, the four strains outperformed Pseudomonas putida KT2440, a strain known as a good root colonizer of different plants. Inoculation with all the isolates improved seed germination and vigor index, particularly in saline conditions, and one of them also had a positive effect on shoot length and phenological state of soybean plants grown in slightly saline soil. Our results suggest that the search for classical plant growth promotion traits may not be mandatory for selecting putative PGPB. Instead, characteristics such as stress tolerance, adhesion, competitive colonization, and plant growth promotion should be tested using the soil types and crops in which the bacteria will be used. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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19 pages, 2445 KiB

Open AccessArticle

Human Waste Substitute Strategies Enhanced Crop Yield, Crop Quality, and Soil Fertility in Vegetable Cultivation Soils in North China

by Bo Liu, Bo Yang, Chunxue Zhang, Xiaocheng Wei, Haoyu Cao and Xiangqun Zheng

Agronomy 2021, 11(11), 2232; https://doi.org/10.3390/agronomy11112232 - 04 Nov 2021

Cited by 3 | Viewed by 2870

Abstract

Replacing chemical fertilizers with human waste for vegetable planting is a traditional, economical, and environmentally friendly waste resource utilization strategy. However, whether the human waste substitute strategy can improve soil fertility and increase crop yield and quality compared to the simple application of [...] Read more.

Replacing chemical fertilizers with human waste for vegetable planting is a traditional, economical, and environmentally friendly waste resource utilization strategy. However, whether the human waste substitute strategy can improve soil fertility and increase crop yield and quality compared to the simple application of chemical fertilizers is still unclear, especially under acidic and alkaline soil conditions. In this study, we studied the effects of different ratios of human waste (urine and feces) to chemical fertilizer on the crop yield, crop quality, soil fertility, and soil chemical parameters in alkaline Cambisols and acidic Alisols cultivated with water spinach (Ipomoea aquatica Forssk.). The application variants of human waste and chemical fertilizer were as follows: (i) Control, no fertilization (CK), (ii) human waste application (HW), (iii) chemical fertilizer application (CF), (iv) 1/3 human waste to chemical fertilizer (P1), and (v) 2/3 human waste to chemical fertilizer (P2). Human waste application increased the total nitrogen, available phosphorus, available potassium, organic matter, NO₃⁻-N, and conductivity in soil, enhanced soil enzyme activity, slowed down soil acidification, and increased the yield, soluble sugar, and vitamin C contents of the water spinach while reducing its nitrate content. Our findings indicate that human waste substitution improved soil fertility while reducing the potential risks of soil acidification, salinization, and human exposure to nitrates. These findings may be applied to increase vegetable production and quality, improve the soil environment, and increase the utilization of human waste as a valuable resource. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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20 pages, 2322 KiB

Open AccessArticle

Nitrogen Use Efficiency in Parent vs. Hybrid Canola under Varying Nitrogen Availabilities

by Shanay T. Williams, Sally Vail and Melissa M. Arcand

Plants 2021, 10(11), 2364; https://doi.org/10.3390/plants10112364 - 02 Nov 2021

Cited by 10 | Viewed by 2513

Abstract

Improving nitrogen use efficiency (NUE) is essential for sustainable agriculture, especially in high-N-demanding crops such as canola (Brassica napus). While advancements in above-ground agronomic practices have improved NUE, research on soil and below-ground processes are limited. Plant NUE—and its components, N [...] Read more.

Improving nitrogen use efficiency (NUE) is essential for sustainable agriculture, especially in high-N-demanding crops such as canola (Brassica napus). While advancements in above-ground agronomic practices have improved NUE, research on soil and below-ground processes are limited. Plant NUE—and its components, N uptake efficiency (NUpE), and N utilization efficiency (NUtE)—can be further improved by exploring crop variety and soil N cycling. Canola parental genotypes (NAM-0 and NAM-17) and hybrids (H151857 and H151816) were grown on a dark brown chernozem in Saskatchewan, Canada. Soil and plant samples were collected at the 5–6 leaf stage and flowering, and seeds were collected at harvest maturity. Soil N cycling varied with phenotypic stage, with higher potential ammonium oxidation rates at the 5–6 leaf stage and higher urease activity at flowering. Seed N uptake was higher under higher urea-N rates, while the converse was true for NUE metrics. Hybrids had higher yield, seed N uptake, NUtE, and NUE, with higher NUE potentially owing to higher NUtE at flowering, which led to higher yield and seed N allocation. Soil N cycling and soil N concentrations correlated for improved canola NUE, revealing below-ground breeding targets. Future studies should consider multiple root characteristics, including rhizosphere microbial N cycling, root exudates, and root system architecture, to determine the below-ground dynamics of plant NUE. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 2248 KiB

Open AccessReview

Fluoride Toxicity Limit—Can the Element Exert a Positive Effect on Plants?

by Zbigniew Jarosz and Karolina Pitura

Sustainability 2021, 13(21), 12065; https://doi.org/10.3390/su132112065 - 01 Nov 2021

Cited by 5 | Viewed by 2183

Abstract

The problem of fluoride toxicity to living organisms is the subject of many studies. Its effect, not always toxic, on the human organism has been well documented. However, although the phytotoxicity of the element has been proved, this issue is still being investigated. [...] Read more.

The problem of fluoride toxicity to living organisms is the subject of many studies. Its effect, not always toxic, on the human organism has been well documented. However, although the phytotoxicity of the element has been proved, this issue is still being investigated. It seems to be still relevant due to the progressive pollution of the environment and fluoridation of water. Assuming that the source of food for humans is plants, the content of fluoride in fruits and vegetables is important for human health. In the available literature, fluoride has been demonstrated to be phytotoxic at the level of cell transformations, biometric plant parameters, development of resistance, and biochemical processes in plants. However, several studies have provided information on improvement of certain plant parameters, e.g., the length of roots or shoots, caused by low fluoride doses and improvement of respiratory indices. The aim of this study was to analyze changes caused in plants by exposure to fluoride and to determine its beneficial effects based on the latest literature reports. It was based on the latest knowledge from the last 8 years. Attempts were made to compare earlier research results with contemporary items. In conclusion, the analysis has shown that, although some sources provide information on the positive effect of small fluoride doses, the impact of this element requires further investigations, as has not been fully elucidated. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 1529 KiB

Open AccessArticle

Effects of Reduced Nitrogen with Bio-Organic Fertilizer on Soil Properties, Yield and Quality of Non-Heading Chinese Cabbage

by Yingbin Qi, Fangling Jiang, Rong Zhou, Ying Wu, Xilin Hou, Jiaxi Li, Wenyuan Lin and Zhen Wu

Agronomy 2021, 11(11), 2196; https://doi.org/10.3390/agronomy11112196 - 30 Oct 2021

Cited by 8 | Viewed by 2800

Abstract

Fertilizer is extremely essential to increasing the yield of vegetables. However, excessively using fertilizers has had a negative impact on the yield and quality of vegetables as well as soil environment in recent years. Non-heading Chinese cabbage ‘yellow rose’ was applied to determine [...] Read more.

Fertilizer is extremely essential to increasing the yield of vegetables. However, excessively using fertilizers has had a negative impact on the yield and quality of vegetables as well as soil environment in recent years. Non-heading Chinese cabbage ‘yellow rose’ was applied to determine the influence of organic manure and inorganic fertilizer on the character of rhizosphere soil, the growth and quality of plants. There were five treatments: conventional fertilization (NF), a total nitrogen reduction of 20% (NF20), a total nitrogen reduction of 30% (NF30), a total nitrogen reduction of 20% with 100 kg·667 m⁻² bio-organic fertilizer (BNF20) and a total nitrogen reduction of 30% with 200 kg·667 m⁻² bio-organic fertilizer (BNF30). The results show that the content of nitrate nitrogen, organic matter in rhizosphere soil treated by BNF20 and BNF30, was significantly enhanced compared with NF. The yield, Vc and soluble protein of plants treated by BNF20 and BNF30 increased by 30.11%, 17.26%, 5.66% and 15.90%, 16.02%, 5.37%, respectively, compared with NF. On the contrary, the nitrate content significantly decreased in plants of BNF20 and BNF30 by 47.87% and 40.98% compared with NF. The significantly positive correlation was observed between nitrate nitrogen content in rhizosphere soil and the yield (p < 0.05). In conclusion, reduced nitrogen with bio-organic fertilizer can improve the yield and quality of ‘yellow rose’ cabbage by improving the quality of rhizosphere soil. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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14 pages, 3445 KiB

Open AccessArticle

Nitrogen Fertilizer Driven Bacterial Community Structure in a Semi-Arid Region of Northeast China

by Meng Wang, Ling Wang, Qian Li, Hang Liu, Yuan Lin and Lichun Wang

Sustainability 2021, 13(21), 11967; https://doi.org/10.3390/su132111967 - 29 Oct 2021

Cited by 1 | Viewed by 1642

Abstract

The soil nitrogen (N) cycle is an essential role of the biogeochemical cycle. Bacteria play an irreplaceable part in the soil N cycle, but the impact of different N gradients on bacterial communities remains unclear. The purpose of this research was to explore [...] Read more.

The soil nitrogen (N) cycle is an essential role of the biogeochemical cycle. Bacteria play an irreplaceable part in the soil N cycle, but the impact of different N gradients on bacterial communities remains unclear. The purpose of this research was to explore the bacterial abundance, community composition, and diversity under different N application rates in a water-limited area. We investigated the bacterial abundance, diversity, community composition, and structure under five different N gradients (0, 90, 150, 210, and 270 kg ha⁻¹) using real-time quantitative PCR and high-throughput sequencing, and then explored bacterial functional groups with FAPROTAX. N application significantly affected bacterial abundance and community composition. Bacterial diversity was enhanced at low N application rates and reduced at higher N application rates. Principal coordinate analysis showed that bacterial community structure was separated into two groups between low N application rates and high N application rates; these differences in bacterial community structure may be driven by available nitrogen (AN). The results of FAPROTAX revealed that N application promoted the functions of Aerobic_nitrite_oxidation, Nitrate_reduction, and Aerobic_ammonia_oxidation, but inhibited the Nitrogen_fixation function of the bacterial community. The high N network caused the reduction of network structure stability. Our results revealed that N fertilizer driven bacterial community structure and soil nutrients were the main influential factors in the variation of bacterial community structure. We suggest that the optimal N application rate in this study may be approximately 150 kg ha⁻¹, based on the variations of soil properties and bacterial community structure in semi-arid areas. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 2947 KiB

Open AccessArticle

Nanoparticles as Potential Improvement for Conventional Fertilisation in the Cultivation of Raphanus sativus var. sativus

by Lidia Mielcarz-Skalska, Beata Smolińska and Katarzyna Włodarczyk

Agriculture 2021, 11(11), 1067; https://doi.org/10.3390/agriculture11111067 - 29 Oct 2021

Cited by 1 | Viewed by 1585

Abstract

The use of nanoparticles in fertilisation has confirmed positive effects on plant growth and yield. Simultaneously, there is still little research into the effects of nanoparticles on the antioxidant system of plants. Due to the positive effect of nano zinc oxide on plants [...] Read more.

The use of nanoparticles in fertilisation has confirmed positive effects on plant growth and yield. Simultaneously, there is still little research into the effects of nanoparticles on the antioxidant system of plants. Due to the positive effect of nano zinc oxide on plants and the special property of nano zero-valent iron, these particles were selected for the research. The nano zero-valent iron is crucial for plants as it is present in agglomerations on the surface of roots where it increases the absorptive surface of the rhizosphere and causes elongation of the roots. The study aims to determine the influence of selected nanoparticles as a potential improvement for conventional fertilisation by magnesium (Mg), calcium (Ca), phosphorus (P) and nitrogen (N). After the cultivation, the influence of nanoparticles on the accumulation of macronutrients in plant tissues, biometric parameters, and physiological response (chlorophyll and antioxidant system) of radish (Raphanus sativus) were assessed. The solution used in this study helped to increase the content of nitrates (V) in radish roots by 31.7–73.2% compared to conventional fertilisation. Nevertheless, nanoparticles supplementation resulted in a decrease in the concentrations of magnesium, iron (Fe) and zinc (Zn) in plants. The high dose of used fertilisers increased the thickness and length of tubers by approximately 50.0%, compared to the control samples. The “Macro 2 + nano” variant caused an increase of plant biomass up to 70.0%. The analysis of the antioxidant system showed that the application of macronutrients with nanoparticles increased the concentration of polyphenols in plant tubers by 46.0–55.6%. Interestingly, while implemented conditions caused a 1.5-fold increase in CAT activity in leaves, at the same time the decrease in CAT activity in plant roots was observed. Based on the obtained results of the enzymatic antioxidant system and biometric parameters of plants, it can be concluded that (in laboratory conditions) nZVI and nanoZnO are efficient components of fertilisers. However, the effects on other organisms must be investigated before implementing a method for widespread use. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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10 pages, 5359 KiB

Open AccessReview

Impacts of Agriculture on the Environment and Soil Microbial Biodiversity

by Adoración Barros-Rodríguez, Pharada Rangseekaew, Krisana Lasudee, Wasu Pathom-aree and Maximino Manzanera

Plants 2021, 10(11), 2325; https://doi.org/10.3390/plants10112325 - 28 Oct 2021

Cited by 12 | Viewed by 4145

Abstract

Agriculture represents an important mechanism in terms of reducing plant, animal, and microbial biodiversity and altering the environment. The pressure to cope with the increasing food demands of the human population has intensified the environmental impact, and alternative ways to produce food are [...] Read more.

Agriculture represents an important mechanism in terms of reducing plant, animal, and microbial biodiversity and altering the environment. The pressure to cope with the increasing food demands of the human population has intensified the environmental impact, and alternative ways to produce food are required in order to minimize the decrease in biodiversity. Conventional agricultural practices, such as floods and irrigation systems; the removal of undesired vegetation by fires, tilling, and plowing; the use of herbicides, fertilizers, and pesticides; and the intensification of these practices over the last 50 years, have led to one of the most important environmental threats—a major loss of biodiversity. In this study, we review the impact that agriculture and its intensification have had on the environment and biodiversity since its invention. Moreover, we demonstrate how these impacts could be reduced through the use of microorganisms as biostimulants. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 2139 KiB

Open AccessArticle

Inorganic Fertilization at High N Rate Increased Olive Yield of a Rainfed Orchard but Reduced Soil Organic Matter in Comparison to Three Organic Amendments

by João I. Lopes, Alexandre Gonçalves, Cátia Brito, Sandra Martins, Luís Pinto, José Moutinho-Pereira, Soraia Raimundo, Margarida Arrobas, Manuel Ângelo Rodrigues and Carlos M. Correia

Agronomy 2021, 11(11), 2172; https://doi.org/10.3390/agronomy11112172 - 28 Oct 2021

Cited by 11 | Viewed by 2018

Abstract

Strategies for waste valorisation from domestic and agro-industrial activities must be pursued, and its use as a soil amendment is an interesting possibility. In this four-year study, the effect of applying municipal solid waste (MSW), farmyard manure (FYM), bottom wood ash supplemented with [...] Read more.

Strategies for waste valorisation from domestic and agro-industrial activities must be pursued, and its use as a soil amendment is an interesting possibility. In this four-year study, the effect of applying municipal solid waste (MSW), farmyard manure (FYM), bottom wood ash supplemented with nitrogen (Ash + N), the inorganic fertilization common in the region (50 kg ha⁻¹ N, P₂O₅ and K₂O) (Control) and this inorganic fertilization supplemented with 70 kg N ha⁻¹ (High N) was assessed in a rainfed olive grove planted in a shallow soil with low organic matter and managed with conventional tillage. The High N treatment significantly increased olive yield in comparison to the other treatments (165% more than MSW), and soil available N proved to be the main driver for tree productivity. MSW and FYM increased soil organic matter, as well as the levels of phosphorus and cation exchange capacity, leaving good indications for future production cycles, although during the four years of the study these treatments provided little N to the trees. The High N treatment significantly reduced soil organic matter (63% less than MSW). The result was attributed in part to the soil management system that did not allow the development of herbaceous vegetation, but also to an effect known as “added N interaction”, in which the excess of inorganic N in the soil might have contributed to accelerate the mineralization of native soil organic matter, an aspect that compromises the sustainability of this fertilization strategy. Although MSW and wood ash are sometimes associated with risks of environmental contamination with heavy metals, in this study the levels of heavy metals in soils and in plant tissues were not of concern. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 2301 KiB

Open AccessArticle

Yield and Economic Response of Modern Cotton Cultivars to Nitrogen Fertilizer

by Irish Lorraine B. Pabuayon, Donna Mitchell-McCallister, Katie L. Lewis and Glen L. Ritchie

Agronomy 2021, 11(11), 2149; https://doi.org/10.3390/agronomy11112149 - 26 Oct 2021

Cited by 5 | Viewed by 2091

Abstract

Non-optimal application of nitrogen (N) fertilizer in cotton (Gossypium hirsutum L.) production systems often results from a producer’s uncertainty in predicting the N rate that ensures maximum economic return. Residual soil nitrate-N (NO₃-N) is also often unaccounted for in fertilizer [...] Read more.

Non-optimal application of nitrogen (N) fertilizer in cotton (Gossypium hirsutum L.) production systems often results from a producer’s uncertainty in predicting the N rate that ensures maximum economic return. Residual soil nitrate-N (NO₃-N) is also often unaccounted for in fertilizer management decisions. In this study, the lint yield and profitability of two cotton cultivars (FiberMax FM 958 and Deltapine DP 1646 B2XF) were compared across five N fertilizer treatments [0 kg ha⁻¹ (control), 45 kg ha⁻¹ (N-45), 90 kg ha⁻¹ (N-90), 135 kg ha⁻¹ (N-135), 180 kg ha⁻¹ (N-180)] from 2018 to 2020. For both cultivars, additional N fertilizer on top of the control treatment did not increase the lint yield of cotton. For each year, both control and N-45 treatments resulted in the greatest revenue above variable costs (RAVC) values for all cultivars. The improved N partitioning efficiency in newer cultivars and the high levels of residual soil NO₃-N allowed sustained plant growth and yield even with reduced N application. Overall, the results show the advantage of reducing N inputs in residual N-rich soils to maintain yield and increase profits. These findings are important in promoting more sustainable agricultural systems through reduced chemical inputs and maintained soil health. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 1627 KiB

Open AccessArticle

Blueberry Yield and Soil Mineral Nitrogen Response to Nitrogen Fertilizer and Nitrification Inhibitors under Drip-Fertigation Systems

by Aimé J. Messiga, Sylvia Nyamaizi, Shaobing Yu and Martine Dorais

Agronomy 2021, 11(11), 2144; https://doi.org/10.3390/agronomy11112144 - 26 Oct 2021

Cited by 2 | Viewed by 2062

Abstract

In blueberry plantings, nitrification can result in losses of mineral nitrogen (N) through leaching because blueberries prefer ammonium (NH₄⁺) over nitrate (NO₃⁻). The objective of this study was to assess the effects of two rates of N [...] Read more.

In blueberry plantings, nitrification can result in losses of mineral nitrogen (N) through leaching because blueberries prefer ammonium (NH₄⁺) over nitrate (NO₃⁻). The objective of this study was to assess the effects of two rates of N fertilizer, mixed or not with nitrification inhibitors (NI) and applied through two fertigation systems, on berry yield and the concentrations of NH₄⁺-N and NO₃⁻-N along the soil profile. Thus, nine combinations of treatments including two N fertilizer rates (60 and 120 kg N ha⁻¹), two NI (with DCD + Nitra-pyrin or without) and two fertigation application methods (buried and suspended drip lines) and a control (0 kg N ha⁻¹) were tested over three years (2016–2018) in a long-term blueberry planting. Berry yield was on average 47.32 Mg ha⁻¹ in 2016 and 26.86 Mg ha⁻¹ in 2018. In 2017, berry yield varied between 8.60 Mg ha⁻¹ under the control and 11.66 Mg ha⁻¹ with 120 kg N ha⁻¹ applied through suspended drip lines. Low berry yield in 2017 was due to a heavy pruning to rejuvenate the plants. In 2016, the concentration of NH₄⁺-N in the sawdust mulch layer varied between 13.1 and 27.1 mg kg⁻¹ in the spring, 11.4 and 32.1 mg kg⁻¹ in the summer, and 7.9 and 72.9 mg kg⁻¹ in the fall; the concentration of high NH₄⁺-N along the soil profile did not exceed 5 mg kg⁻¹. High concentrations of NH₄⁺-N in the sawdust mulch layer were associated with NI, but did not translate to high berry yields. The concentration of NO₃⁻-N in the soil profile reached 42.6 mg kg⁻¹ in the summer and 39.0 mg kg⁻¹ in the fall and these high concentrations were associated with NI. In 2017 and 2018, there was no effect of NI on NH₄⁺-N concentrations even in the layer of sawdust mulch which was not consistent with the results obtained in 2016. High concentrations of NO₃⁻-N were measured beneath the sawdust mulch layer with treatments including N fertilizer alone or mixed with NI. It is possible that NH₄⁺ retained in the layer of sawdust mulch and not taken up by plant roots was subsequently oxidized to NO₃⁻ at the end of the residence time of NI in the soil. Our results showed that high concentrations of NO₃⁻-N along the soil profile occurred mainly during the summer which could be explained by irrigation water driving NO₃⁻ leaching. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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21 pages, 2437 KiB

Open AccessArticle

Combination of Compost and Mineral Fertilizers as an Option for Enhancing Maize (Zea mays L.) Yields and Mitigating Greenhouse Gas Emissions from a Nitisol in Ethiopia

by Gebeyanesh Worku Zerssa, Dong-Gill Kim, Philipp Koal and Bettina Eichler-Löbermann

Agronomy 2021, 11(11), 2097; https://doi.org/10.3390/agronomy11112097 - 20 Oct 2021

Cited by 8 | Viewed by 3212

Abstract

Combined application of organic and mineral fertilizers has been proposed as a measure for sustainable yield intensification and mitigation of greenhouse gas (GHG) emissions. However, fertilizer effects strongly depend on the soil type and still no precise information is available for Nitisols in [...] Read more.

Combined application of organic and mineral fertilizers has been proposed as a measure for sustainable yield intensification and mitigation of greenhouse gas (GHG) emissions. However, fertilizer effects strongly depend on the soil type and still no precise information is available for Nitisols in Ethiopia. The study evaluated effects of different ratios of biowaste compost and mineral fertilizers (consisting of nitrogen (N), phosphorus (P), and sulphur (S)) on maize (Zea mays L. Bako-hybrid) yields in a two-year field trial. Soil samples from each treatment of the field trial were used to estimate emissions of nitrous oxide (N₂O), carbon dioxide (CO₂), methane (CH₄), and microbial activity in a 28-day incubation experiment with two moisture levels (40% and 75% water-filled pore space, WFPS). The application of fertilizers corresponded to a N supply of about 100 kg ha⁻¹, whereby the pure application of mineral fertilizers (100 min) was gradually replaced by compost. Maize yields were increased by 12 to 18% (p < 0.05) in the combined treatments of compost and mineral fertilizers compared to the 100 min treatment. The cumulative emissions of N₂O and CO₂ but not CH₄ were affected by the fertilizer treatments and soil moisture levels (p < 0.05). At 75% WFPS, the N₂O emissions in the 100 min treatment was with 16.3 g ha⁻¹ more than twice as high as the treatment with 100% compost (6.4 g ha⁻¹) and also considerably higher than in the 50% compost treatment (9.4 g ha⁻¹). The results suggest that a compost application accounting for 40 to 70% of the N supply in the fertilizer combinations can be suitable to increase maize yields as well as to mitigate GHG emissions from Nitisols in Southwestern Ethiopia. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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12 pages, 1330 KiB

Open AccessArticle

The Role of Cover Crop Types and Residue Incorporation in Improving Soil Chemical Properties

by Rimsha Khan, Aitazaz A. Farooque, Helen Carolyn Peach Brown, Qamar U. Zaman, Bishnu Acharya, Farhat Abbas and Andrew McKenzie-Gopsill

Agronomy 2021, 11(10), 2091; https://doi.org/10.3390/agronomy11102091 - 19 Oct 2021

Cited by 2 | Viewed by 2498

Abstract

Soil chemical properties can be improved by incorporating crop residues in soil and letting it decompose. This study explored the use of incorporating residues of cover crops for improvements in soil chemical properties including soil organic matter (SOM), soil pH, and the selected [...] Read more.

Soil chemical properties can be improved by incorporating crop residues in soil and letting it decompose. This study explored the use of incorporating residues of cover crops for improvements in soil chemical properties including soil organic matter (SOM), soil pH, and the selected soil macro- and micronutrients in greenhouse and field trials. Factors of interest included (i) cover crops and their combinations and (ii) methods of crop termination and incorporation in soil (disc, mow + disc, glyphosate, roller crimper). The greenhouse trial showed up to a 20% higher amount of SOM accumulated in soils incorporated with crop residues. Buckwheat (3.12%) and phacelia (3.12%) produced significantly different and larger SOM than that of the control treatment that received no crop residues (p ≤ 0.05). The soil pH of the brown mustard treatment was also significantly affected by the experimental treatments (p ≤ 0.05). The incorporation of crop residues did not affect soil phosphorous (P) or potassium (K) concentrations, except for brown mustard, with significantly higher values of P and K than the control treatment. Calcium (Ca) was significantly higher in the soil of phacelia + pea treatment (p ≤ 0.05). Buckwheat + pea produced a higher concentration of Ca (1028 mg/kg) followed by buckwheat alone (1006 mg/kg). Analysis of variance (ANOVA) calculated on the results of the field trial showed that the mix treatment that had a mixture of four cover crops significantly increased the SOM content. Buckwheat produced the highest (2.95%) SOM, then brown mustard and timothy. This study concludes that, irrespective of the tillage incorporation methods, the residues from cover crops are a potential source of improvement in soil health, and this practice may promote sustainable agriculture in conditions similar to those in this study. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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16 pages, 31660 KiB

Open AccessArticle

Nutrient Release and Ammonia Volatilization from Biochar-Blended Fertilizer with and without Densification

by Yit Leng Lee, Osumanu Haruna Ahmed, Samsuri Abdul Wahid, Mohamadu Boyie Jalloh and Adiza Alhassan Muzah

Agronomy 2021, 11(10), 2082; https://doi.org/10.3390/agronomy11102082 - 18 Oct 2021

Cited by 3 | Viewed by 2583

Abstract

Blending fertilizer with biochar followed by densification to make it into a tablet can enhance the adsorption of fertilizer on the biochar surface and reduce the nutrient loss during handling. However, the nutrient release and ammonia volatilization from biochar-blended fertilizer with and without [...] Read more.

Blending fertilizer with biochar followed by densification to make it into a tablet can enhance the adsorption of fertilizer on the biochar surface and reduce the nutrient loss during handling. However, the nutrient release and ammonia volatilization from biochar-blended fertilizer with and without densification are not well understood. The objectives of this study were to determine the nutrient release and ammonia volatilization from an acid soil applied with biochar-blended NPK fertilizer with and without densification. The nutrient release of biochar-blended NPK was determined using water incubation for 30 days, whereas daily loss of ammonia was measured using a closed dynamic air flow system for 10 days. The densified biochar-blended NPK caused stronger physical binding of the nutrients within the tablet in addition to stronger chemical bondings between the nutrients with the biochar’s functional groups. As a result, nutrient release in the water incubation from the biochar-blended NPK fertilizer tablet was slower. However, blending the biochar with the NPK fertilizer increased soil ammonia volatilization relative to the NPK fertilizer alone. This demonstrates that the biochar-blended fertilizer tablet has the potential to serve as a slow release fertilizer for crop cultivation. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 11373 KiB

Open AccessArticle

Evaluation of Metabolomic Profile and Growth of Moringa oleifera L. Cultivated with Vermicompost under Different Soil Types

by Luis Alberto Manzano-Gómez, Jorge Martín Guzmán-Albores, Reiner Rincón-Rosales, Robert Winkler, Clara Ivette Rincón-Molina, José Humberto Castañón-González, Nancy Ruiz-Lau, Federico Antonio Gutiérrez-Miceli, Francisco Alexander Rincón-Molina and Víctor Manuel Ruíz-Valdiviezo

Agronomy 2021, 11(10), 2061; https://doi.org/10.3390/agronomy11102061 - 14 Oct 2021

Cited by 3 | Viewed by 2374

Abstract

Moringa oleifera is a highly versatile plant with potential use in the agro-food and biochemical industry. The goals of this study were to evaluate the effect of chemical fertilization and vermicompost on plant growth, and to analyze the metabolomic profile of M. oleifera [...] Read more.

Moringa oleifera is a highly versatile plant with potential use in the agro-food and biochemical industry. The goals of this study were to evaluate the effect of chemical fertilization and vermicompost on plant growth, and to analyze the metabolomic profile of M. oleifera crops cultivated over agricultural and native soils. The extracts were obtained from 90-day-old leaves via extraction with a hydroalcoholic mixture. Multivariate data analyses, such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA), were used to differentiate the distribution of leaf metabolites according to the soils or types of fertilizers used for the cultivation of Moringa oleifera. The results indicated that there was no significant effect on parameters such as plant height, root length and dry weight of leaves (p < 0.05). UPLC-ESI-MS/MS analysis of leaf extracts revealed a wide range of flavonoids, alkaloids and organic acids. The results of PCA and PLS-DA confirmed that the type of fertilizer had an effect on the metabolomic profile of M. oleifera leaves. The application of vermicompost induced changes in the metabolomic profile, but not in the morphometric variables of Moringa oleifera. These results are important for metabolite production via organic cultures and over different soil types in the industrialization of Moringa. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 1411 KiB

Open AccessArticle

Interactions between Biochar and Compost Treatment and Mycorrhizal Fungi to Improve the Qualitative Properties of a Calcareous Soil under Rhizobox Conditions

by Roghayeh Vahedi, MirHassan Rasouli-Sadaghiani, Mohsen Barin and Ramesh Raju Vetukuri

Agriculture 2021, 11(10), 993; https://doi.org/10.3390/agriculture11100993 - 13 Oct 2021

Cited by 7 | Viewed by 2923

Abstract

Most calcareous soils have relatively low levels of organic matter. To evaluate the effect of pruning waste biochar (PWB) and pruning waste compost (PWC) combined with arbuscular mycorrhizal fungi (AMF) on the biological indices, a rhizobox study on wheat using a completely randomized [...] Read more.

Most calcareous soils have relatively low levels of organic matter. To evaluate the effect of pruning waste biochar (PWB) and pruning waste compost (PWC) combined with arbuscular mycorrhizal fungi (AMF) on the biological indices, a rhizobox study on wheat using a completely randomized design was conducted under greenhouse conditions. The studied factors included the source of organic material (PWB, PWC, and control), the microbial inoculation (+AMF or −AMF), and the zone (rhizosphere and non-rhizosphere soil). At the end of the plant growth period, organic carbon (OC), microbial biomass carbon (MBC), microbial biomass phosphorous (MBP), microbial respiration (BR), substrate-induced respiration (SIR), and alkaline (ALP) and acid (ACP) phosphatase enzyme activities in the rhizosphere and non-rhizosphere soils were determined. Simultaneous application of a source of organic matter and AMF inoculation significantly increased the OC and biological indices of soil relative to those observed when applying organic matter without AMF inoculation. Additionally, MBC, MBP, ACP, and ALP enzymes activities in the rhizosphere zone were significantly higher than in the non-rhizosphere. AMF increased BR and SIR levels in the rhizosphere by 13.06% and 7.95% compared to those in the non-rhizosphere, respectively. It can be concluded that PWC and PWB can improve soil biological properties by increasing microbial activity. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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15 pages, 300 KiB

Open AccessArticle

Response of Seeds, Oil Yield and Fatty Acids Percentage of Jojoba Shrub Strain EAI to Mycorrhizal Fungi and Moringa Leaves Extract

by Amira K. G. Atteya, Rokayya Sami, Amina A. M. Al-Mushhin, Khadiga Ahmed Ismail and Esmail A. E. Genaidy

Horticulturae 2021, 7(10), 395; https://doi.org/10.3390/horticulturae7100395 - 13 Oct 2021

Cited by 6 | Viewed by 1943

Abstract

Jojoba seeds have a unique storage lipid wax which is suitable as a basic feedstock in the chemical industry. For saving both human health and the environment, there is a continuous need to search for alternative safe natural sources of plant nutrients. Therefore, [...] Read more.

Jojoba seeds have a unique storage lipid wax which is suitable as a basic feedstock in the chemical industry. For saving both human health and the environment, there is a continuous need to search for alternative safe natural sources of plant nutrients. Therefore, in this study the effect of mycorrhizal fungi and Moringa oleifera leaves extract on growth, flowering, fruits set, yield and the chemical composition of the jojoba shrub was studied. The application of a combination of treatments of 20 g L⁻¹ mycorrhizal fungi plus 30 g L⁻¹Moringa oleifera leaves extract recorded the maximum mean values of main branch length, length of secondary branches, number of branched nodes, number of secondary branches, flowering percentage, final fruit set percentage, seeds yield per shrub and per hectare, percentage of minerals, proteins as well as oil yield per shrub and per hectare, chlorophyll a and b, N, P, K percentage with a minimum mean value of the number of days until full bloom in both seasons. The maximum percentage of Gadoleic fatty acid was found with the combination treatment of uninoculation plus 10 g L⁻¹Moringa oleifera leaves extract. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

8 pages, 1248 KiB

Open AccessArticle

Optimum Castor Meal Application in the Cultivation of Pak Choi (Brassica chinensis L.) with Toxicity Survey for Earthworms (Eisenia andrei)

by Zheng-Shang Liu, Jia-Mei Wu and Yong-Hong Lin

Horticulturae 2021, 7(10), 383; https://doi.org/10.3390/horticulturae7100383 - 09 Oct 2021

Viewed by 2113

Abstract

In Taiwan, castor meal (CM) is often used by farmers as an organic fertilizer for the supplement of plant nutrition. It can rapidly increase nitrogen availability for crops. However, the excessive application of CM will affect the ecosystem. This study was conducted to [...] Read more.

In Taiwan, castor meal (CM) is often used by farmers as an organic fertilizer for the supplement of plant nutrition. It can rapidly increase nitrogen availability for crops. However, the excessive application of CM will affect the ecosystem. This study was conducted to evaluate the optimum concentration of CM that can be used as a fertilizer for balancing crop production and soil ecosystem health (by considering earthworms). Pak choi was selected for the experiment. A randomized block design with three replications was used, with treatments consisting of five concentrations of CM (namely 25, 50, 100, 150, and 200 kg/0.1 ha) and fermented livestock compost 800 kg/0.1 ha, represented as CM₂₅, CM₅₀, CM₁₀₀, CM₁₅₀, CM₂₀₀, and LC₈₀₀, respectively. The results revealed that soil properties, leaf nutrient concentration, and plant traits, namely plant diameter, plant height, and fresh and dry root and shoot matter, improved with the increasing concentrations of CM, and CM₁₀₀–CM₂₀₀, and led to the highest production of pak choi which was equivalent to that with LC₈₀₀. However, the weight of earthworms decreased as CM concentrations increased. The weight of earthworms was similar between CM₂₅, CM₅₀, CM₁₀₀, and LC₈₀₀. In conclusion, given the characteristics of high nitrogen as a fertilizer, the optimal dose of CM was 100–150 kg/0.1 ha for obtaining a balance between crop production and ecosystem safety. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 1111 KiB

Open AccessArticle

The Transformation Dynamics and Homogeneity of Different N Fractions in Compost following Glucose Addition

by Caibin Li, Shuai Ding, Chenghang Du, Yi He, Zemeng Ma, Guitong Li and Zhencai Sun

Agriculture 2021, 11(10), 971; https://doi.org/10.3390/agriculture11100971 - 07 Oct 2021

Cited by 1 | Viewed by 1770

Abstract

The application of compost to soil is a common fertilization practice for improving soil quality and crop growth. The isotopic labeling technique is mostly used to investigate the contribution of compost N to crop uptake. However, compost N includes various N fractions and [...] Read more.

The application of compost to soil is a common fertilization practice for improving soil quality and crop growth. The isotopic labeling technique is mostly used to investigate the contribution of compost N to crop uptake. However, compost N includes various N fractions and labeling dissimilarity, which may cause bias when calculating the compost N contribution to plants. Therefore, the labeling dynamics of different N fractions in compost and the homogenous labeling time point should be clarified. Given the ¹⁵N-labeling in chemical fertilizer and the carbon source, i.e., glucose, the compost N pools were divided into active N (mineral N, soluble organic N [SON], microbial biomass N [MBN]), stable N (hot-water extractable organic N [HWDON]), and recalcitrant N. The atom percentage excess (APE) of different N in compost notably varied at the beginning of incubation, ranging from 0–3.7%. After the addition of glucose, biological N immobilization was promoted (13.7% and 28.8% for MBN and HWDON, respectively) and promoted the transformation among available N pools. Adding distinct doses of glucose at three stages to ¹⁵N-labeled compost resulted in diverse microbial responses, thereby redistributing exogenous N in each fraction (¹⁵NH₄⁺-N went into SO¹⁵N from day 15 to day 30 and increased by 5.1%; SO¹⁵N entered MB¹⁵N and HWDO¹⁵N during day 30 to day 45 and increased by 5.7% and 5.2%, respectively). On day 45, homogeneous ¹⁵N-labeled compost was achieved, which was 2.4% for ¹⁵N APE for all N fractions. Overall, the quantitative data for the transformation of N fractions in compost at distinct stages provides a scientific basis for compost labeling trials, in order to identify the time point at which compost N-labeling is homogeneous, which is necessary and meaningful to reduce the bias of the contribution rate of compost-N to plants. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 1501 KiB

Open AccessArticle

Estimation of Iodine Leaching in Soil Amended with Organic and Inorganic Materials Using HYDRUS 1-D Model

by Muhammad Mohiuddin, Jawad Ali, Megersa Kebede Leta, Muhammad Waseem, Muhammad Irshad and Zahid Hussain

Sustainability 2021, 13(19), 10967; https://doi.org/10.3390/su131910967 - 02 Oct 2021

Cited by 3 | Viewed by 2063

Abstract

This study investigated the ability of a HYDRUS 1D model for predicting the vertical distribution of potassium iodine (200 ppm) in soil columns after amendment with five different common remediation materials (gypsum, lime, fly ash, charcoal, and sawdust) at a rate of 2.5% [...] Read more.

This study investigated the ability of a HYDRUS 1D model for predicting the vertical distribution of potassium iodine (200 ppm) in soil columns after amendment with five different common remediation materials (gypsum, lime, fly ash, charcoal, and sawdust) at a rate of 2.5% (w/w), relative to an unamended control soil. Results showed that relative to the unamended soil, iodine leaching was decreased by all amendments but that the magnitude of the decreases varied with the soil amendment applied. Iodine content was highest in the upper layer of the soil columns and decreased progressively with soil depth. The model was evaluated via comparison of the model simulated values with measured values from the soil column studies. The results showed that the HYDRUS 1D model efficiency was near to 1, indicating the stimulated results near to the measured values. Therefore, this study showed that iodine leaching through a soil could be ascertained well using a HYDRUS 1D model. The model over predicted iodine leaching, results in a weak correspondence between the simulated and the measured results for iodine leaching. This suggests that the HYDRUS-1D model does not explain accurately different organic and inorganic amended soil and the preferential flow that occurs in these columns. This may be due to the fact that Freundlich isotherm, which is part of the transport equations, does not sufficiently describe the mechanism of iodine adsorption onto the soil particles. This study would help to select an amendment for an effective management strategy to reduce exogenous iodine losses from agro-ecosystems. This would also improve scientific understanding of iodine transport in soil profile. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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18 pages, 1340 KiB

Open AccessArticle

Optimizing Tomato Growth and Productivity Using Nitrogen and Irrigation Application Timing

by Ibukun T. Ayankojo and Kelly T. Morgan

Agronomy 2021, 11(10), 1968; https://doi.org/10.3390/agronomy11101968 - 29 Sep 2021

Cited by 4 | Viewed by 2290

Abstract

Soil nutrients and water management practices according to the concept of 4R nutrient stewardship (right rate, right timing, right placement, and right source) can have significant benefits on crop productivity and reduce the negative effects of agricultural practices on the environment. Therefore, this [...] Read more.

Soil nutrients and water management practices according to the concept of 4R nutrient stewardship (right rate, right timing, right placement, and right source) can have significant benefits on crop productivity and reduce the negative effects of agricultural practices on the environment. Therefore, this present study evaluated the effects of nitrogen (N) application timing under different irrigation regimes on open-field, fresh-market tomato production in Florida. In this study, 2 N application timings applied at 25% pre-plant with 75% fertigation (BM), and 0 pre-plant with 100% fertigation (NB), were evaluated. The two N application methods were evaluates using three irrigation regimes: full irrigation (FI, 100% ETc), deficit irrigation (DI, 66% ETc), and regulated deficit irrigation (RDI, 66% ETc during the first 4 weeks after transplanting and 100% ETc afterward). The results showed that BM treatment significantly improved early-season tomato growth compared to NB treatment. The results also indicated that under RDI and DI irrigation conditions, tomato root length was lowest (average value of 13%) within the first 15 cm compared to 40% within 15–30 cm and 47% at 30–40 cm soil depths. Similar to plant growth, BM treatment significantly increased tomato yield (average valued 56.00 Mg ha⁻¹) compared to the NB (average value 40.23 Mg ha⁻¹). The application of DI throughout the growing season reduced tomato yield; however, there were no differences in yield under the RDI and FI irrigation regimes. Therefore, based on the results from this study, it can be concluded that, under Florida growing conditions, pre-plant N application is essential for tomato growth and productivity. Additionally, irrigation application using the RDI method could be successfully adopted in Florida tomato production for improved water savings without any negative effects on tomato growth and productivity. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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13 pages, 885 KiB

Open AccessArticle

Influence of Tillage on the Mollisols Physicochemical Properties, Seed Emergence and Yield of Maize in Northeast China

by Qiang Chen, Xingyi Zhang, Li Sun, Jianhua Ren, Yaru Yuan and Shuying Zang

Agriculture 2021, 11(10), 939; https://doi.org/10.3390/agriculture11100939 - 28 Sep 2021

Cited by 9 | Viewed by 2095

Abstract

Tillage practices are critical for sustaining soil quality necessary for successful crop growth and productivity, but there are only few studies for strip tillage (ST) in the Mollisols region of Northeast China at present. A long-term (≥10-year) study was carried out to investigate [...] Read more.

Tillage practices are critical for sustaining soil quality necessary for successful crop growth and productivity, but there are only few studies for strip tillage (ST) in the Mollisols region of Northeast China at present. A long-term (≥10-year) study was carried out to investigate the influence of within the tilled row (IR) and between rows (BR) in ST (10-year), conventional tillage (CT, 14-year) and no tillage (NT, 14-year) treatments on soil physicochemical properties. Soil samples were taken in May of 2019 at 0–5, 5–10, 10–20 and 20–30 cm depths and used to analyze bulk density (BD), soil aggregate distribution and stability, and soil organic carbon (SOC). Meanwhile, our study also explored the differences in seed emergence, soil moisture, and temperature during the seed emergence period, and yield of maize (Zea mays L.) among the different treatments. Similar soil properties were observed between ST-BR and NT, which showed they had a significantly greater BD, >0.25 mm water stable aggregate content (WR_0.25) (especially in the amount of >2 mm and 1–2 mm size proportion), aggregate stability, and SOC than ST-IR and CT-IR at a depth of 0–20 cm. By improving soil conditions of seedbed, ST-IR and CT-IR increased soil temperature above NT by 1.64 °C and 1.80 °C, respectively, and ST-IR had a slight greater soil moisture than CT-IR in the top 10 cm layer during the seed emergence period. Late maize seed emergence was observed NT in than ST-IR and CT-IR and the average annual yields in ST were slightly greater than NT and CT, but the differences were not significant. Our results also showed that CT-BR had a poor soil structure and lower SOC than other treatments at 0–30 cm depth. We conclude from these long-term experimental results that ST could improve soil water-heat conditions to promote seed germination, maintain soil structure, and increase the maize yield and it should be applied in the Mollisols region of Northeast China. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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11 pages, 1812 KiB

Open AccessArticle

Effects of Soil pH on Gaseous Nitrogen Loss Pathway via Feammox Process

by Ding Ma, Jin Wang, Jun Xue, Zhengbo Yue, Shaofeng Xia, Lei Song and Hongwen Gao

Sustainability 2021, 13(18), 10393; https://doi.org/10.3390/su131810393 - 17 Sep 2021

Cited by 9 | Viewed by 2201

Abstract

The application of N fertilizer is one of the most critical soil acidification factors in China, and soil acidification significantly alters biogeochemical processes such as N loss. Anaerobic ammonium oxidation coupled with iron reduction (Feammox) is an important biological process for N loss [...] Read more.

The application of N fertilizer is one of the most critical soil acidification factors in China, and soil acidification significantly alters biogeochemical processes such as N loss. Anaerobic ammonium oxidation coupled with iron reduction (Feammox) is an important biological process for N loss in natural environments, with the end-products of N₂, NO₂⁻ and NO₃⁻. However, the response of Feammox pathways to soil pH fluctuation has not been thoroughly studied. In the current study, Feammox pathways and microbial communities were explored through a slurry culture experiment with an artificially adjusted pH combined with a ¹⁵N isotope tracing technique and molecular biotechnology. Results showed significant differences in the gaseous N loss through Feammox (0.42–0.97 mg N kg⁻¹ d⁻¹) under different pH conditions. The gaseous N loss pathways were significantly affected by the pH, and Feammox to N₂ was the predominant pathway in low-pH incubations. The proportion of N loss caused by Feammox coupled with denitrification increased as the soil pH increased. The gaseous N loss through Feammox increased by 43.9% when the soil pH decreased from 6.5 to 5.0. Fe-reducing bacteria, such as Ochrobactrum, Sphingomonas, and Clostridium increased significantly in lower pH incubations. Overall, this study demonstrated the effects of soil pH on Feammox pathways and extended the understanding of the N biogeochemical cycle in acidic soil. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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Open AccessArticle

Growth, Mineral Nutrients, Photosynthesis and Related Physiological Parameters of Citrus in Response to Nitrogen Deficiency

by Wei-Tao Huang, Yi-Zhi Xie, Xu-Feng Chen, Jiang Zhang, Huan-Huan Chen, Xin Ye, Jiuxin Guo, Lin-Tong Yang and Li-Song Chen

Agronomy 2021, 11(9), 1859; https://doi.org/10.3390/agronomy11091859 - 16 Sep 2021

Cited by 27 | Viewed by 3409

Abstract

Limited data are available on the physiological responses of Citrus to nitrogen (N) deficiency. ‘Xuegan’ (Citrus sinensis (L.) Osbeck) and ‘Shantian pummelo’ (Citrus grandis (L.) Osbeck) seedlings were fertilized with nutrient solution at a N concentration of 0, 5, 10, 15 [...] Read more.

Limited data are available on the physiological responses of Citrus to nitrogen (N) deficiency. ‘Xuegan’ (Citrus sinensis (L.) Osbeck) and ‘Shantian pummelo’ (Citrus grandis (L.) Osbeck) seedlings were fertilized with nutrient solution at a N concentration of 0, 5, 10, 15 or 20 mM for 10 weeks. N deficiency decreased N uptake and N concentration in leaves, stems and roots and disturbed nutrient balance and homeostasis in plants, thus inhibiting plant growth, as well as reducing photosynthetic pigment levels and impairing thylakoid structure and photosynthetic electron transport chain (PETC) in leaves, hence lowering CO₂ assimilation. The imbalance of nutrients intensified N deficiency’s adverse impacts on biomass, PETC, CO₂ assimilation and biosynthesis of photosynthetic pigments. Citrus displayed adaptive responses to N deficiency, including (a) elevating the distributions of N and other elements in roots, as well as root dry weight (DW)/shoot DW ratio and root-surface-per-unit volume and (b) improving photosynthetic N use efficiency (PNUE). In general, N deficiency had less impact on biomass and photosynthetic pigment levels in C. grandis than in C. sinensis seedlings, demonstrating that the tolerance of C. grandis seedlings to N deficiency was slightly higher than that of C. sinensis seedlings, which might be related to the higher PNUE of the former. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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