Agronomy

14 pages, 2493 KiB

Open AccessEditor’s ChoicePerspective

Landscape Epidemiology of Xylella fastidiosa in the Balearic Islands

by Diego Olmo, Alicia Nieto, David Borràs, Marina Montesinos, Francesc Adrover, Aura Pascual, Pere A. Gost, Bàrbara Quetglas, Alejandro Urbano, Juan de Dios García, María Pilar Velasco-Amo, Concepción Olivares-García, Omar Beidas, Andreu Juan, Ester Marco-Noales, Margarita Gomila, Juan Rita, Eduardo Moralejo and Blanca B. Landa

Agronomy 2021, 11(3), 473; https://doi.org/10.3390/agronomy11030473 - 4 Mar 2021

Cited by 39 | Viewed by 4921

Abstract

Xylella fastidiosa (Xf) is a vascular plant pathogen native to the Americas. In 2013, it was first reported in Europe, implicated in a massive die-off of olive trees in Apulia, Italy. This finding prompted mandatory surveys across Europe, successively revealing that [...] Read more.

Xylella fastidiosa (Xf) is a vascular plant pathogen native to the Americas. In 2013, it was first reported in Europe, implicated in a massive die-off of olive trees in Apulia, Italy. This finding prompted mandatory surveys across Europe, successively revealing that the bacterium was already established in some distant areas of the western Mediterranean. To date, the Balearic Islands (Spain) hold the major known genetic diversity of Xf in Europe. Since October 2016, four sequence types (ST) belonging to the subspecies fastidiosa (ST1), multiplex (ST7, ST81), and pauca (ST80) have been identified infecting 28 host species, including grapevines, almond, olive, and fig trees. ST1 causes Pierce’s disease (PD) and together with ST81 are responsible for almond leaf scorch disease (ALSD) in California, from where they were introduced into Mallorca in around 1993, very likely via infected almond scions brought for grafting. To date, almond leaf scorch disease affects over 81% of almond trees and Pierce’s disease is widespread in vineyards across Mallorca, although producing on average little economic impact. In this perspective, we present and analyze a large Xf-hosts database accumulated over four years of field surveys, laboratory sample analyses, and research to understand the underlying causes of Xf emergence and spread among crops and wild plants in the Balearic Islands. The impact of Xf on the landscape is discussed. Full article

(This article belongs to the Special Issue Diagnosis, Population Biology and Management of Vascular Diseases)

► Show Figures

Figure 1

4 pages, 180 KiB

Open AccessEditor’s ChoiceEditorial

Special Issue “Genetics, Genomics, and Breeding of Legume Crops”

by Guo-Liang Jiang

Agronomy 2021, 11(3), 475; https://doi.org/10.3390/agronomy11030475 - 4 Mar 2021

Cited by 1 | Viewed by 2078

Abstract

Legume crops are grown in the world primarily for their grain seeds that are widely used for human and animal consumption or for the production of oils for industrial uses [...] Full article

(This article belongs to the Special Issue Genetics, Genomics, and Breeding of Legume Crops)

15 pages, 6257 KiB

Open AccessEditor’s ChoiceArticle

Apple Detection in Complex Scene Using the Improved YOLOv4 Model

by Lin Wu, Jie Ma, Yuehua Zhao and Hong Liu

Agronomy 2021, 11(3), 476; https://doi.org/10.3390/agronomy11030476 - 4 Mar 2021

Cited by 66 | Viewed by 8115

Abstract

To enable the apple picking robot to quickly and accurately detect apples under the complex background in orchards, we propose an improved You Only Look Once version 4 (YOLOv4) model and data augmentation methods. Firstly, the crawler technology is utilized to collect pertinent [...] Read more.

To enable the apple picking robot to quickly and accurately detect apples under the complex background in orchards, we propose an improved You Only Look Once version 4 (YOLOv4) model and data augmentation methods. Firstly, the crawler technology is utilized to collect pertinent apple images from the Internet for labeling. For the problem of insufficient image data caused by the random occlusion between leaves, in addition to traditional data augmentation techniques, a leaf illustration data augmentation method is proposed in this paper to accomplish data augmentation. Secondly, due to the large size and calculation of the YOLOv4 model, the backbone network Cross Stage Partial Darknet53 (CSPDarknet53) of the YOLOv4 model is replaced by EfficientNet, and convolution layer (Conv2D) is added to the three outputs to further adjust and extract the features, which make the model lighter and reduce the computational complexity. Finally, the apple detection experiment is performed on 2670 expanded samples. The test results show that the EfficientNet-B0-YOLOv4 model proposed in this paper has better detection performance than YOLOv3, YOLOv4, and Faster R-CNN with ResNet, which are state-of-the-art apple detection model. The average values of Recall, Precision, and F1 reach 97.43%, 95.52%, and 96.54% respectively, the average detection time per frame of the model is 0.338 s, which proves that the proposed method can be well applied in the vision system of picking robots in the apple industry. Full article

► Show Figures

Figure 1

14 pages, 1058 KiB

Open AccessEditor’s ChoiceReview

Benefits and Limitations of Non-Transgenic Micronutrient Biofortification Approaches

by Edward Marques, Heather M. Darby and Jana Kraft

Agronomy 2021, 11(3), 464; https://doi.org/10.3390/agronomy11030464 - 3 Mar 2021

Cited by 29 | Viewed by 9236

Abstract

Increasing the amount of micronutrients in diets across the world is crucial to improving world health. Numerous methods can accomplish this such as the biofortification of food through biotechnology, conventional breeding, and agronomic approaches. Of these, biofortification methods, conventional breeding, and agronomic approaches [...] Read more.

Increasing the amount of micronutrients in diets across the world is crucial to improving world health. Numerous methods can accomplish this such as the biofortification of food through biotechnology, conventional breeding, and agronomic approaches. Of these, biofortification methods, conventional breeding, and agronomic approaches are currently globally accepted and, therefore, should be the primary focus of research efforts. This review synthesizes the current literature regarding the state of biofortified foods through conventional breeding and agronomic approaches for crops. Additionally, the benefits and limitations for all described approaches are discussed, allowing us to identify key areas of research that are still required to increase the efficacy of these methods. The information provided here should provide a basal knowledge for global efforts that are combating micronutrient deficiencies. Full article

(This article belongs to the Special Issue From Biofortification to Tailored Crops and Food Products)

► Show Figures

Figure 1

12 pages, 1818 KiB

Open AccessEditor’s ChoiceArticle

Integrated Effects of Potassium Humate and Planting Density on Growth, Physiological Traits and Yield of Vicia faba L. Grown in Newly Reclaimed Soil

by Ayman H. A. Mahdi, Shimaa A. Badawy, Arafat Abdel Hamed Abdel Latef, Ahmed A. A. El Hosary, Usama A. Abd El Razek and Ragab S. Taha

Agronomy 2021, 11(3), 461; https://doi.org/10.3390/agronomy11030461 - 2 Mar 2021

Cited by 20 | Viewed by 3904

Abstract

Several agronomic factors, including planting density, affect plant growth and final yield. New soil suffers from severe fertility shortage and crop productivity. Potassium humate (KH) application improves soil fertility and plant performance under new soil conditions. Therefore, this investigation was performed in two [...] Read more.

Several agronomic factors, including planting density, affect plant growth and final yield. New soil suffers from severe fertility shortage and crop productivity. Potassium humate (KH) application improves soil fertility and plant performance under new soil conditions. Therefore, this investigation was performed in two seasons of 2018/2019 and 2019/2020 to study the impact of KH application at the rate of 50 kg hectare⁻¹ (ha⁻¹) on growth, yield, physio-biochemical attributes, plant water status and nutrients in faba bean plants grown in newly reclaimed soil under three planting densities, i.e., D₁ = 222.222 plants ha⁻¹ (15 × 60 cm), D₂ = 166.666 plants ha⁻¹ (20 × 60 cm) and D₃ = 133.333 plants ha⁻¹ (25 × 60 cm). The results showed that KH application enhanced tissue water status by increasing the membrane stability index (MSI%) and relative water content (RWC%), while electric leakage (EL%) was reduced, alongside increased growth attributes physio-biochemical properties and nutrients. These results were positively reflected by the improved yield and its components (i.e., number of pods plant⁻¹, 100-seed weight, seed yield plant⁻¹ and seed yield ha⁻¹) in favor of the medium planting density (166.666 plants ha⁻¹). The results of the current study showed that the application of KH with the medium planting density (20 × 60 cm) was the best treatment combination to enhance the performance and productivity (2.97 ton ha⁻¹) of faba bean plants grown under newly reclaimed soil conditions. Full article

(This article belongs to the Section Innovative Cropping Systems)

► Show Figures

Figure 1

17 pages, 371 KiB

Open AccessEditor’s ChoiceReview

The Pros and Cons of Rye Chromatin Introgression into Wheat Genome

by Kinga Moskal, Sylwia Kowalik, Wiesław Podyma, Bogusław Łapiński and Maja Boczkowska

Agronomy 2021, 11(3), 456; https://doi.org/10.3390/agronomy11030456 - 1 Mar 2021

Cited by 22 | Viewed by 3530

Abstract

Rye is one of the most commonly used sources of elite genes in wheat improvement programs. Due to the high collinearity of the genomes of both cereal species, it is possible to obtain interspecific chromosomal translocations and substitution lines. Rye chromatin is used [...] Read more.

Rye is one of the most commonly used sources of elite genes in wheat improvement programs. Due to the high collinearity of the genomes of both cereal species, it is possible to obtain interspecific chromosomal translocations and substitution lines. Rye chromatin is used to transfer numerous genes for resistance to biotic and abiotic stresses into the wheat genome. Introgression has also resulted in improved agronomic traits. However, despite the numerous advantages, the transfer of large fragments or whole chromosomes has been quite often accompanied by a decrease in end-use quality. This paper presents an overview of the benefits and drawbacks of using rye as a source of variability in wheat breeding. Full article

(This article belongs to the Special Issue Hybrid Breeding: Future Status and Future Prospects)

29 pages, 4899 KiB

Open AccessEditor’s ChoiceReview

Zeolites Enhance Soil Health, Crop Productivity and Environmental Safety

by Mousumi Mondal, Benukar Biswas, Sourav Garai, Sukamal Sarkar, Hirak Banerjee, Koushik Brahmachari, Prasanta Kumar Bandyopadhyay, Sagar Maitra, Marian Brestic, Milan Skalicky, Peter Ondrisik and Akbar Hossain

Agronomy 2021, 11(3), 448; https://doi.org/10.3390/agronomy11030448 - 28 Feb 2021

Cited by 75 | Viewed by 11554

Abstract

In modern days, rapid urbanisation, climatic abnormalities, water scarcity and quality degradation vis-à-vis the increasing demand for food to feed the growing population necessitate a more efficient agriculture production system. In this context, farming with zeolites, hydrated naturally occurring aluminosilicates found in sedimentary [...] Read more.

In modern days, rapid urbanisation, climatic abnormalities, water scarcity and quality degradation vis-à-vis the increasing demand for food to feed the growing population necessitate a more efficient agriculture production system. In this context, farming with zeolites, hydrated naturally occurring aluminosilicates found in sedimentary rocks, which are ubiquitous and environment friendly, has attracted attention in the recent past owing to multidisciplinary benefits accrued from them in agricultural activities. The use of these minerals as soil ameliorants facilitates the improvement of soil’s physical and chemical properties as well as alleviates heavy metal toxicity. Additionally, natural and surface-modified zeolites have selectivity for major essential nutrients, including ammonium (NH₄⁺), phosphate (PO₄²⁻), nitrate (NO₃⁻), potassium (K⁺) and sulphate (SO₄²⁻), in their unique porous structure that reduces nutrient leaching. The slow-release nature of zeolites is also beneficial to avail nutrients optimally throughout crop growth. These unique characteristics of zeolites improve the fertilizer and water use efficiency and, subsequently, diminish environmental pollution by reducing nitrate leaching and the emissions of nitrous oxides and ammonia. The aforesaid characteristics significantly improve the growth, productivity and quality of versatile crops, along with maximising resource use efficiency. This literature review highlights the findings of previous studies as well as the prospects of zeolite application for achieving sustenance in agriculture without negotiating the output. Full article

(This article belongs to the Special Issue Sustainable Agricultural Practices—Impact on Soil Quality and Plant Health)

► Show Figures

Figure 1

9 pages, 1994 KiB

Open AccessEditor’s ChoiceArticle

Could Entomophagy Be an Effective Mitigation Measure in Desert Locust Management?

by Ahmed Ali Samejo, Riffat Sultana, Santosh Kumar and Samiullah Soomro

Agronomy 2021, 11(3), 455; https://doi.org/10.3390/agronomy11030455 - 28 Feb 2021

Cited by 17 | Viewed by 3538

Abstract

The desert locust has been a notorious pest since ancient times. A population upsurge hit Pakistan in 2019 and caused tremendous damage to agriculture and livelihoods. To take advantage of this ongoing upsurge, we conducted a field study to verify whether locust collection [...] Read more.

The desert locust has been a notorious pest since ancient times. A population upsurge hit Pakistan in 2019 and caused tremendous damage to agriculture and livelihoods. To take advantage of this ongoing upsurge, we conducted a field study to verify whether locust collection could be an interesting control method to protect crops in the event of an invasion, as well as an accepted food resource for poor rural communities. A village in the Thar desertic region was selected as a type-locality. An awareness campaign was launched to promote the collection and consumption of locusts as well as to alert people of their nutritional value. Two large swarms arrived near the village and several other swarms affected places nearby. Around 3033 kg of locusts were collected through handpicking at night. Most of the locusts were eaten and, as a result, hoppers of the next generation did not emerge in the type-locality; however, hopper bands appeared in areas where entomophagy was not practiced. The study area had less locust activity because swarms could not lay eggs due to entomophagy by the villagers. The consumption of desert locusts could be an effective practice to prevent malnutrition and protein deficiency and, to a certain extent, an efficient mitigation measure to help local populations to better protect themselves and their crops against locust outbreaks. Collection and consumption of locusts should be encouraged while remaining realistic about its real impact on locust control. This should also be done in concert with local authorities to take into account the risks to human health and to avoid the consumption of insects treated with pesticides. Full article

(This article belongs to the Special Issue How to Manage Migratory Pests and Potential Food Crises: Locusts Plagues in the 2020’s)

► Show Figures

Figure 1

27 pages, 485 KiB

Open AccessEditor’s ChoiceReview

Genetic Diversity of Barley Foliar Fungal Pathogens

by Arzu Çelik Oğuz and Aziz Karakaya

Agronomy 2021, 11(3), 434; https://doi.org/10.3390/agronomy11030434 - 27 Feb 2021

Cited by 17 | Viewed by 4220

Abstract

Powdery mildew, net blotch, scald, spot blotch, barley stripe, and leaf rust are important foliar fungal pathogens of barley. Fungal leaf pathogens negatively affect the yield and quality in barley plant. Virulence changes, which can occur in various ways, may render resistant plants [...] Read more.

Powdery mildew, net blotch, scald, spot blotch, barley stripe, and leaf rust are important foliar fungal pathogens of barley. Fungal leaf pathogens negatively affect the yield and quality in barley plant. Virulence changes, which can occur in various ways, may render resistant plants to susceptible ones. Factors such as mutation, population size and random genetic drift, gene and genotype flow, reproduction and mating systems, selection imposed by major gene resistance, and quantitative resistance can affect the genetic diversity of the pathogenic fungi. The use of fungicide or disease-resistant barley genotypes is an effective method of disease control. However, the evolutionary potential of pathogens poses a risk to overcome resistance genes in the plant and to neutralize fungicide applications. Factors affecting the genetic diversity of the pathogen fungus may lead to the emergence of more virulent new pathotypes in the population. Understanding the factors affecting pathogen evolution, monitoring pathogen biology, and genetic diversity will help to develop effective control strategies. Full article

(This article belongs to the Special Issue Genetic Diversity of Disease Resistance in Crops)

15 pages, 1008 KiB

Open AccessEditor’s ChoiceArticle

Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?

by Agnieszka Ludwiczak, Monika Osiak, Stefany Cárdenas-Pérez, Sandra Lubińska-Mielińska and Agnieszka Piernik

Agronomy 2021, 11(3), 435; https://doi.org/10.3390/agronomy11030435 - 27 Feb 2021

Cited by 40 | Viewed by 4576

Abstract

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known [...] Read more.

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants. Full article

(This article belongs to the Section Soil and Plant Nutrition)

► Show Figures

Figure 1

13 pages, 582 KiB

Open AccessEditor’s ChoiceArticle

Improving Nutrient Uptake, Growth, Yield and Protein Content in Chickpea by the Co-Addition of Phosphorus Fertilizers, Organic Manures, and Bacillus sp. MN-54

by Muhammad Imran Khan, Muhammad Junaid Afzal, Safdar Bashir, Muhammad Naveed, Sara Anum, Sardar Alam Cheema, Abdul Wakeel, Muhammad Sanaullah, Muhammad Hayder Ali and Zhongbing Chen

Agronomy 2021, 11(3), 436; https://doi.org/10.3390/agronomy11030436 - 27 Feb 2021

Cited by 21 | Viewed by 4022

Abstract

The main purpose of this study was to examine the impact of different phosphorus (P) fertilizers and organic manures alone and in combination with Bacillus sp. MN-54 on growth, yield, nutrient uptake, chlorophyll (SPAD value) and crude proteins content of chickpea. The simple [...] Read more.

The main purpose of this study was to examine the impact of different phosphorus (P) fertilizers and organic manures alone and in combination with Bacillus sp. MN-54 on growth, yield, nutrient uptake, chlorophyll (SPAD value) and crude proteins content of chickpea. The simple manure (SM), processed manure (PM), single super phosphate (SSP), and rock phosphate (RP) were applied individually and in different combinations to the soil in pots, and the chickpea seeds treated with Bacillus sp. MN-54 were sown in the selective pots. Results showed that individual use of SM, PM, SSP, RP, and strain MN-54 significantly increased (P ≤ 0.05) the nutrient uptake, growth, yield, and protein content of chickpea as compared to control treatments. While the combined use of SM or PM, SSP or RP, and MN-54 further enhanced this effect. Among different treatments, combined use of RP, PM and MN-54 proved the most effective treatment showing increase of 37.5 and 42.6% in shoot and root lengths, 43.4 and 38.3% in fresh and dry shoot weights, 36.1 and 36.5% in fresh and dry root weights, 45.8% in no. of pods, 43.6% in nodules counts, 16.0% in 100-grain weight and 31–36% nutrient uptake over control treatments. Our findings suggest that the co-addition of organic manures and P fertilizers along with plant growth promoting bacteria (i.e., Bacillus sp. MN-54) not only increases the growth and yield but also improves nodulation, nutrient uptake, and crude proteins content in chickpea. Full article

(This article belongs to the Section Soil and Plant Nutrition)

► Show Figures

Figure 1

15 pages, 883 KiB

Open AccessEditor’s ChoiceArticle

Agronomic Traits in Oilseed Rape (Brassica napus) Can Predict Foraging Resources for Insect Pollinators

by Stacey M. Fairhurst, Lorna J. Cole, Tereza Kocarkova, Catherine Jones-Morris, Andy Evans and Gail Jackson

Agronomy 2021, 11(3), 440; https://doi.org/10.3390/agronomy11030440 - 27 Feb 2021

Cited by 6 | Viewed by 4483

Abstract

Mass-flowering crops, such as oilseed rape (OSR; Brassica napus), provide pulses of nectar and pollen, helping to support pollinators and their pollination services in agricultural landscapes. Despite their value to declining pollinators, varietal in-field OSR testing focusses on agronomic traits, with floral [...] Read more.

Mass-flowering crops, such as oilseed rape (OSR; Brassica napus), provide pulses of nectar and pollen, helping to support pollinators and their pollination services in agricultural landscapes. Despite their value to declining pollinators, varietal in-field OSR testing focusses on agronomic traits, with floral resources being largely overlooked. OSR has a high varietal turnover, and consequently, floral resource data collected for a specific variety quickly become redundant. Here, we explore the potential to predict floral resource availability using agronomic trait data routinely collected in varietal trials. To build predictive models, we investigated the relationships between agronomic traits and pollen and nectar availability in 19 OSR varieties. Nectar quality was positively influenced by early vigour, as well as winter hardiness in conventional varieties and stem stiffness in hybrid varieties. Pollen quantity was driven by different traits, with early maturation having a negative impact in conventional varieties and resistance to lodging having a positive impact in hybrid varieties. Our study highlights the potential to predict floral resources using agronomic trait data, enabling the rapid assessment of these key resources in future OSR varieties without costly sampling. Agronomic traits relating to increased nectar quality were also agronomically favourable, indicating benefits to both pollinators and growers. The inclusion of modelled floral resource data in recommended varietal lists would enable growers to make informed decisions about varietal selection based on local pollinator populations. Full article

(This article belongs to the Section Crop Breeding and Genetics)

► Show Figures

Figure 1

14 pages, 1876 KiB

Open AccessEditor’s ChoiceArticle

Post-Harvest Management Practices Impact on Light Penetration and Kernza Intermediate Wheatgrass Yield Components

by Priscila Pinto, Lee De Haan and Valentin Picasso

Agronomy 2021, 11(3), 442; https://doi.org/10.3390/agronomy11030442 - 27 Feb 2021

Cited by 20 | Viewed by 3110

Abstract

Kernza intermediate wheatgrass (Thinopyrum intermedium) is the first commercially developed perennial grain crop in North America, with multiple environmental and economic benefits. One of the major challenges for adoption of this dual-use forage and grain crop is the decline in grain [...] Read more.

Kernza intermediate wheatgrass (Thinopyrum intermedium) is the first commercially developed perennial grain crop in North America, with multiple environmental and economic benefits. One of the major challenges for adoption of this dual-use forage and grain crop is the decline in grain yield in subsequent harvest years. Post-harvest management practices (e.g., chopping, burning, chemical, and mechanical thinning) could reduce the intraspecific competition for light and maintain Kernza grain yields over time. We aimed to identify management practices that improve light penetration and propose a conceptual model to explain the mechanisms contributing to Kernza grain yield. We applied 10 management practices after the first Kernza grain harvest in a randomized complete block design experiment with three replications, at two different locations in Wisconsin, USA. Light penetration increased when post-harvest management practices were applied. Mechanical or chemical thinning had relatively lower lodging and increased yield components per row, but not per area due to a reduction in the number of productive rows. Threshed grain yield per area in the second year of Kernza was similar among the treatments despite the differences in vegetative biomass generated. Further research is needed to optimize management practices to maintain Kernza grain yield over time. Full article

(This article belongs to the Special Issue Multifunctional Forages)

► Show Figures

Figure 1

21 pages, 3140 KiB

Open AccessEditor’s ChoiceArticle

Adaptation Responses to Early Drought Stress of West Africa Sorghum Varieties

by Boubacar Gano, Joseph Sékou B. Dembele, Thierry Klanvi Tovignan, Bassirou Sine, Vincent Vadez, Diaga Diouf and Alain Audebert

Agronomy 2021, 11(3), 443; https://doi.org/10.3390/agronomy11030443 - 27 Feb 2021

Cited by 30 | Viewed by 4286

Abstract

Sorghum is the fifth most important cereal crop world-wide and feeds millions of people in the Sahel. However, it often faces early-stage water deficit due to false onsets of rainy seasons resulting in production decrease. Therefore, developing early drought tolerant material becomes a [...] Read more.

Sorghum is the fifth most important cereal crop world-wide and feeds millions of people in the Sahel. However, it often faces early-stage water deficit due to false onsets of rainy seasons resulting in production decrease. Therefore, developing early drought tolerant material becomes a necessity but requires a good knowledge of adaptation mechanisms, which remains to be elucidated. The present study aimed at assessing the effects of early drought stress on ten elite sorghum varieties tested over two years (2018–2019) at the National Agronomic Research Centre (CNRA) of Bambey (Senegal, West Africa). Two different water regimes (well-watered and drought stress) were applied during the dry season. Water stress was applied by withholding irrigation 25 days after sowing for one month, followed by optimal irrigation until maturity. Soil moisture measurements were performed and allowed to follow the level of stress (down to a fraction of transpirable soil water (FTSW) of 0.30 at the end of stress). An agro-physio-morphological monitoring was carried out during the experiment. Results showed highly significant effects of early drought stress in sorghum plants growth by decreasing leaf appearance, biomass, height but also yield set up. The combined analysis of variance revealed highly significant differences (p ≤ 0.01) between varieties in the different environments for most characters. Under water deficit, the variability was less strong on leaf appearance and plant height at the end of stress. The adaptation responses were related to the capacity of varieties to grow up fast and complete their cycle rather, increase the dead leaves weight, reduce photosynthesis rate, stomatal conductance, leaf transpiration and increase the roots length density. However, varieties V1, V2, V8 and V9 showed promising behavior under stress and could be suitable for further application in West Africa for sorghum breeding and farming. Full article

► Show Figures

Figure 1

16 pages, 1625 KiB

Open AccessEditor’s ChoiceArticle

Differing Phosphorus Crop Availability of Aluminium and Calcium Precipitated Dairy Processing Sludge Potential Recycled Alternatives to Mineral Phosphorus Fertiliser

by S.M. Ashekuzzaman, Owen Fenton, Erik Meers and Patrick J. Forrestal

Agronomy 2021, 11(3), 427; https://doi.org/10.3390/agronomy11030427 - 26 Feb 2021

Cited by 16 | Viewed by 3519

Abstract

The European dairy industry generates large volumes of wastewater from milk and dairy food processing. Removal of phosphorus (P) by complexing with metal (e.g., aluminium, calcium) cations in P rich sludge is a potential P source for agricultural reuse and P recycling. However, [...] Read more.

The European dairy industry generates large volumes of wastewater from milk and dairy food processing. Removal of phosphorus (P) by complexing with metal (e.g., aluminium, calcium) cations in P rich sludge is a potential P source for agricultural reuse and P recycling. However, there is a significant knowledge gap concerning the plant availability of this complexed P in comparison to conventional mineral P fertiliser. The current absence of information on plant P bioavailability of dairy processing sludge (DPS) limits the ability of farmers and nutrient management advisors to incorporate it correctly into fertiliser programmes. The present study examined the most common types of dairy sludge—(1) aluminium-precipitated sludge (“Al-DPS”) and (2) calcium-precipitated lime-stabilised sludge (“Ca-DPS”) at field scale to assess P availability in grassland versus mineral P fertiliser over a growing season. The experimental design was a randomised complete block with five replications. Crop yield and P uptake were assessed for 4 harvests. The initial soil test P was at a low level and the experimental treatments were super phosphate at 15, 30, 40, 50 and 60 kg P ha⁻¹, two dairy sludge applied at 40 kg P ha⁻¹ (comparison was made with mineral P at same application rate) and a zero P control applied in a single application at the beginning of the growing season. Results showed a significant positive slope in the relationship between P uptake response and mineral P application rate indicating the suitability of the experimental site for P availability assessment. The P bioavailability of Al- and Ca-DPS varied greatly between treatments. The P fertiliser replacement value based on the 1st harvest was 50 and 16% increased to 109 and 31% cumulatively over the four harvests for Al- and Ca-DPS, respectively. The Al concentration in Al-DPS did not limit P bioavailability, but low P bioavailability from Ca-DPS can be associated with its high Ca content that can lead to formation of low soluble Ca-P compounds at alkaline pH conditions with a high Ca/P ratio. These findings show that P availability from dairy sludge can be quite different depending on treatment process. Consequently, it is critical to have P availability information as well as total P content available to ensure the application rate meets crop requirements without creating environmental risk by over application. Full article

(This article belongs to the Special Issue Integrated Nutrient Recovery from Organic Waste and Bio-Based Fertilizers)

► Show Figures

Figure 1

16 pages, 1202 KiB

Open AccessEditor’s ChoiceArticle

Analysis of Four Delineation Methods to Identify Potential Management Zones in a Commercial Potato Field in Eastern Canada

by Abdelkarim Lajili, Athyna N. Cambouris, Karem Chokmani, Marc Duchemin, Isabelle Perron, Bernie J. Zebarth, Asim Biswas and Viacheslav I. Adamchuk

Agronomy 2021, 11(3), 432; https://doi.org/10.3390/agronomy11030432 - 26 Feb 2021

Cited by 14 | Viewed by 3849

Abstract

Management zones (MZs) are delineated areas within an agricultural field with relatively homogenous soil properties, and therefore similar crop fertility requirements. Consequently, such MZs can often be used for site-specific management of crop production inputs. This study evaluated the effectiveness of four classification [...] Read more.

Management zones (MZs) are delineated areas within an agricultural field with relatively homogenous soil properties, and therefore similar crop fertility requirements. Consequently, such MZs can often be used for site-specific management of crop production inputs. This study evaluated the effectiveness of four classification methods for delineating MZs in an 8-ha commercial potato field located in Prince Edward Island, Canada. The apparent electrical conductivity (EC_a) at two depths from a commercial Veris sensor were used to delineate MZs using three classification methods without spatial constraints (i.e., fuzzy k-means, ISODATA and hierarchical) and one with spatial constraints (i.e., spatial segmentation method). Soil samples (0.0–0.15 m depth) from 104 sampling points was used to measure soil physical and chemical properties and their spatial variation in the field were used as reference data to evaluate four delineation methods. Significant Pearson correlations between EC_a and soil properties were obtained (0.22 < r < 0.85). The variance reduction indicated that two to three MZs were optimal for representing the field’s spatial variability of soil properties. For two MZs, most soil physical and chemical properties differed significantly between MZs for all four delineation methods. For three MZs, there was greater discrimination among MZs for several soil properties for the spatial segmentation-based method compared with other delineation methods. Moreover, consideration of the spatial coordinates of the data improved the delineation of MZs and thereby increased the number of significant differences among MZs for individual soil properties. Therefore, the spatial segmentation method had the greatest efficiency in delineation of MZs from statistical and agronomic perspectives. Full article

(This article belongs to the Special Issue Machine Learning Applications in Digital Agriculture)

► Show Figures

Figure 1

16 pages, 4038 KiB

Open AccessEditor’s ChoiceSystematic Review

Soil Properties Prediction for Precision Agriculture Using Visible and Near-Infrared Spectroscopy: A Systematic Review and Meta-Analysis

by Arman Ahmadi, Mohammad Emami, Andre Daccache and Liuyue He

Agronomy 2021, 11(3), 433; https://doi.org/10.3390/agronomy11030433 - 26 Feb 2021

Cited by 54 | Viewed by 8310

Abstract

Reflectance spectroscopy for soil property prediction is a non-invasive, fast, and cost-effective alternative to the standard laboratory analytical procedures. Soil spectroscopy has been under study for decades now with limited application outside research. The recent advancement in precision agriculture and the need for [...] Read more.

Reflectance spectroscopy for soil property prediction is a non-invasive, fast, and cost-effective alternative to the standard laboratory analytical procedures. Soil spectroscopy has been under study for decades now with limited application outside research. The recent advancement in precision agriculture and the need for the spatial assessment of soil properties have raised interest in this technique. The performance of soil spectroscopy differs from one site to another depending on the soil’s physical composition and chemical properties but it also depends on the instrumentation, mode of use (in-situ/laboratory), spectral range, and data analysis methods used to correlate reflectance data to soil properties. This paper uses the systematic review procedure developed by the Centre for Evidence-Based Conservation (CEBC) for an evidence-based search of soil property prediction using Visible (V) and Near-InfraRed (NIR) reflectance spectroscopy. Constrained by inclusion criteria and defined methods for literature search and data extraction, a meta-analysis is conducted on 115 articles collated from 30 countries. In addition to the soil properties, findings are also categorized and reported by different aspects like date of publication, journals, countries, employed regression methods, laboratory or in-field conditions, spectra preprocessing methods, samples drying methods, spectroscopy devices, wavelengths, number of sites and samples, and data division into calibration and validation sets. The arithmetic means of the coefficient of determination (R²) over all the reports for different properties ranged from 0.68 to 0.87, with better predictions for carbon and nitrogen content and lower performance for silt and clay. After over 30 years of research on using V-NIR spectroscopy to predict soil properties, this systematic review reveals solid evidence from a literature search that this technology can be relied on as a low-cost and fast alternative for standard methods of soil properties prediction with acceptable accuracy. Full article

(This article belongs to the Special Issue Advances in Irrigation Technology and Adaptation to Climate Change)

► Show Figures

Figure 1

4 pages, 197 KiB

Open AccessEditor’s ChoiceEditorial

Extraction and Analysis of Natural Product in Plant

by Gerardo F. Barbero

Agronomy 2021, 11(3), 415; https://doi.org/10.3390/agronomy11030415 - 25 Feb 2021

Cited by 8 | Viewed by 2432

Abstract

Plants are well known for being a major source of natural compounds, many of them generally considered of biological interest for their antioxidant, anti-inflammatory, antimicrobial or anti-cancerogenic properties [...] Full article

(This article belongs to the Special Issue Extraction and Analysis of Natural Product in Plant)

25 pages, 672 KiB

Open AccessEditor’s ChoiceReview

Evaluation of Various Nitrogen Indices in N-Fertilizers with Inhibitors in Field Crops: A Review

by Antigolena Folina, Alexandros Tataridas, Antonios Mavroeidis, Angeliki Kousta, Nikolaos Katsenios, Aspasia Efthimiadou, Ilias S. Travlos, Ioannis Roussis, Mohammed K. Darawsheh, Panagiota Papastylianou and Ioanna Kakabouki

Agronomy 2021, 11(3), 418; https://doi.org/10.3390/agronomy11030418 - 25 Feb 2021

Cited by 36 | Viewed by 5856

Abstract

Nitrogen (N) management remains a global challenge for the sustainability of diversified farming systems. Field crops are often over-supplied with nitrogen by farmers aiming to high productivity. Although the increase of nitrogen rates leads in many instances to high yields, degree of effectiveness [...] Read more.

Nitrogen (N) management remains a global challenge for the sustainability of diversified farming systems. Field crops are often over-supplied with nitrogen by farmers aiming to high productivity. Although the increase of nitrogen rates leads in many instances to high yields, degree of effectiveness for nitrogen use remains low. Urease and nitrification inhibitors are technologies which have been present in the fertilizers market at least 50 years. Inhibitors exploitation ensures long-term nitrogen release and improved N-uptake by plants and N-storage in seeds and silage. Avail of inhibitors, such as the decline of nitrogen leaching in form of NO₃⁻, reduction of emissions in NH₃ form, and rise of yield, are some of the desirable attributes that are derived from their integration in fertilization schedules. This review reports the evaluation of applied nitrogen, with inhibitors, and field crops based on nitrogen indices. The examined N-indicators include Nitrogen use efficiency (NUE), Nitrogen Utilization Efficiency (NUtE,) Nitrogen Agronomic Efficiency (NAE), Nitrogen Harvest Index (NHI), and N uptake. This review gathered all, to the best of our knowledge, available data regarding the utilization of nitrification and urease inhibitors under an exclusively agronomic perspective. Either dual or single use of nitrification and urease inhibitors has been reported to significantly increase yield components and promote nitrogen uptake. To conclude, the assessment of N-related indices is vital to promoting sustainability in diversified farming systems, while the integration of inhibitors in national N fertilizations schemes may contribute to system profitability through enhancement of N-supply to crops. Full article

(This article belongs to the Special Issue Effect of Biotic and Abiotic Factors on Plant Growth and Nutritional Value of Field and Vegetable Crops)

► Show Figures

Figure 1

24 pages, 2445 KiB

Open AccessEditor’s ChoiceReview

Nitrogen Gap Amelioration Is a Core for Sustainable Intensification of Agriculture—A Concept

by Witold Grzebisz and Remigiusz Łukowiak

Agronomy 2021, 11(3), 419; https://doi.org/10.3390/agronomy11030419 - 25 Feb 2021

Cited by 22 | Viewed by 3355

Abstract

The main reason for the development of the yield gap in crop production is the inefficient management of nitrogen (N). The nitrogen gap (NG) cannot be ameliorated without an indication and quantification of soil characteristics that limit N uptake by a crop plant. [...] Read more.

The main reason for the development of the yield gap in crop production is the inefficient management of nitrogen (N). The nitrogen gap (NG) cannot be ameliorated without an indication and quantification of soil characteristics that limit N uptake by a crop plant. The insufficient supply of N to a plant during its cardinal stages of yield formation is a result of two major-variabilities. The first is spatial variability in the soil characteristics responsible for water supply to a plant, also serving as a nutrient carrier. The second is a vertical variability in soil factors, decisive for pools of available nutrients, and their in-season accessibility to the grown crop. The long-term strategy for NG cover should focus first on soil characteristics (humus stock, pH, nutrient content) responsible for water storage and its availability to the currently grown plant. Diagnostics of plant nutrient availability should deliver data on their contents both in the topsoil and subsoil. The combined use of both classical diagnostic tools and spectral imagery is a way to divide a single field into units, differing in productivity. Remote-sensing techniques offer a broad number of tools to define the in-season crop canopy requirement for fertilizer N in homogenous field units. Full article

(This article belongs to the Special Issue Site-Specific Nutrient Management)

► Show Figures

Figure 1

13 pages, 3573 KiB

Open AccessEditor’s ChoiceArticle

Systematic Investigations of the ZF-HD Gene Family in Tobacco Reveal Their Multiple Roles in Abiotic Stresses

by Jinhao Sun, Minmin Xie, Xiaoxu Li, Zhiyuan Li, Qi Wang, Anming Ding, Weifeng Wang and Yuhe Sun

Agronomy 2021, 11(3), 406; https://doi.org/10.3390/agronomy11030406 - 24 Feb 2021

Cited by 12 | Viewed by 3662

Abstract

Zinc finger homeodomain (ZF-HD) transcription factors play significant roles in plant growth and responses to environmental stresses. In this study, 32 ZF-HD genes identified in the tobacco (Nicotiana tabacum L.) genome were divided into six groups according to phylogenetic analysis with Arabidopsis [...] Read more.

Zinc finger homeodomain (ZF-HD) transcription factors play significant roles in plant growth and responses to environmental stresses. In this study, 32 ZF-HD genes identified in the tobacco (Nicotiana tabacum L.) genome were divided into six groups according to phylogenetic analysis with Arabidopsis and tomato ZF-HD members. An examination of gene structures and conserved motifs revealed the relatively conserved exon/intron structures and motif organization within each subgroup. In addition, various stress-related elements are found in the promoter region of these genes. The expression profiling analysis revealed that NtZF-HD genes expressed in different tissues and could be induced by several abiotic stresses. Notably, NtZF-HD21 was highly expressed in response to the drought treatments. Subcellular localization analysis and a virus-induced gene silencing (VIGS) experiment were performed to investigate the potential functions of NtZF-HD21. The subcellular localization indicated that NtZF-HD21 is a nuclear protein. Furthermore, gene silencing of the NtZF-HD21 gene reduced the drought resistance of tobacco. These findings provide insights for further biological functional analyses of the NtZF-HD genes in tobacco. Full article

(This article belongs to the Special Issue Drought Resistance Mechanisms in Crops)

► Show Figures

Figure 1

21 pages, 7541 KiB

Open AccessEditor’s ChoiceArticle

Planting Density Interferes with Strawberry Production Efficiency in Southern Brazil

by Juliana Martins de Lima, Paola Daiane Welter, Marllon Fernando Soares dos Santos, Wanda Kavcic, Bruna Miranda Costa, Antonio Felippe Fagherazzi, Francine Regianini Nerbass, Aike Anneliese Kretzschmar, Leo Rufato and Gianluca Baruzzi

Agronomy 2021, 11(3), 408; https://doi.org/10.3390/agronomy11030408 - 24 Feb 2021

Cited by 19 | Viewed by 5764

Abstract

In the search for more efficient production systems, many changes have occurred in the strawberry production sector. Planting density is one of the management techniques that most interferes with the quality of fruits and production aspects. This study aimed to evaluate the effect [...] Read more.

In the search for more efficient production systems, many changes have occurred in the strawberry production sector. Planting density is one of the management techniques that most interferes with the quality of fruits and production aspects. This study aimed to evaluate the effect of different planting densities on the photosynthetic characteristics, fruit quality, and production of the strawberry cultivar Pircinque. The study was conducted in the 2018/2019 and 2019/2020 harvests in Lages, Santa Catarina, Brazil. The treatments consisted of plant spacing of 5, 10, 15, 20, 25, and 30 cm. The experimental design was in randomized blocks, with four blocks and plots of 20 plants. Plant spacing interfered with fruit quality, photosynthetic efficiency, production, productivity, and economic return. Due to the fruits of Pircinque having a higher quality than other cultivars, the planting spacing between 5 and 15 cm allows meeting the fruit’s main production and quality requirements. However, it is up to the producer to adapt the management if opting for higher planting densities, which allow for a greater economic viability of the business. Full article

(This article belongs to the Special Issue Strawberry Production in a Protected Environment and under Field Conditions)

► Show Figures

Figure 1

17 pages, 5138 KiB

Open AccessEditor’s ChoiceArticle

Lead (Pb)-Induced Oxidative Stress Alters the Morphological and Physio-Biochemical Properties of Rice (Oryza sativa L.)

by Murtaza Khan, Nkulu Kabange Rolly, Tiba Nazar Ibrahim Al Azzawi, Muhammad Imran, Bong-Gyu Mun, In-Jung Lee and Byung-Wook Yun

Agronomy 2021, 11(3), 409; https://doi.org/10.3390/agronomy11030409 - 24 Feb 2021

Cited by 37 | Viewed by 4002

Abstract

Lead (Pb) is one of the major environmental heavy metal pollutants, known as being neither essential nor beneficial for any living organisms, and which is detrimental to plant fitness, growth, and productivity, as well as human health. This study investigated the changes in [...] Read more.

Lead (Pb) is one of the major environmental heavy metal pollutants, known as being neither essential nor beneficial for any living organisms, and which is detrimental to plant fitness, growth, and productivity, as well as human health. This study investigated the changes in the morphological, physiological, and biochemical properties of rice cultivars exposed to lead (Pb). Therefore, soil was contaminated with a solution containing 0.6 mM or 1.2 mM Pb four weeks prior to transplanting. Then, 4-week-old rice seedlings of Tunnae, Ilmi, Yasmen, Mashkab, and Amber Barka were transplanted into the contaminated soil and grown until maturity. The results showed that a high concentration of lead (1.2 mM) induced significant reduction in the plant height, number of tillers, number of panicles per plant, and the number of spikelets per panicle in Pb-sensitive rice cultivars, while in Pb-tolerant cultivars, a balanced growth of plants and non-significant change in the major yield components were recorded. However, all rice cultivars showed a reduced biomass dry weight. Under the same conditions, we observed a differential enzymatic antioxidant activity, with catalase (CAT) and peroxidase (POD) being the most active. In addition, the proline accumulation and sucrose content increased concomitant with an increase in the Pb concentration, while the total protein and chlorophyll contents significantly decreased. Of all the soluble sugars analyzed, sucrose was the most abundant in response to Pb treatment. Interestingly, the rice cultivars Tunnae and Mashkab exhibited a high degree of tolerance towards Pb stress, with a balanced plant height, number of tillers, number of panicles, and number of spikelets per plant. Therefore, all results collectively suggest that the tolerance to Pb-induced oxidative stress observed in Tunnae and Mashkab could be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems, leading to a balanced reduction–oxidation status in rice. Full article

(This article belongs to the Special Issue Redox-Mediated Signaling in Plants under Stress Conditions)

► Show Figures

Figure 1

24 pages, 5343 KiB

Open AccessEditor’s ChoiceArticle

Mycobiome Composition and Diversity under the Long-Term Application of Spent Mushroom Substrate and Chicken Manure

by Magdalena Frąc, Giorgia Pertile, Jacek Panek, Agata Gryta, Karolina Oszust, Jerzy Lipiec and Bogusław Usowicz

Agronomy 2021, 11(3), 410; https://doi.org/10.3390/agronomy11030410 - 24 Feb 2021

Cited by 24 | Viewed by 3632

Abstract

Waste exogenous organic matter, including spent mushroom substrate (SMS) and chicken manure (CM), can be used as the basis of a soil-improving cropping system in sustainable agriculture. However, there is—as yet—a lack of information about important quality indicators such as the fungal community [...] Read more.

Waste exogenous organic matter, including spent mushroom substrate (SMS) and chicken manure (CM), can be used as the basis of a soil-improving cropping system in sustainable agriculture. However, there is—as yet—a lack of information about important quality indicators such as the fungal community relative abundance, structure and biodiversity in soils treated with these additives. In this study, the responses of the soil fungal community composition and mycobiome diversity to SMS and CM application compared to the control soil were evaluated using a combination of the following molecular approaches: quantitative polymerase chain reactions, denaturing gradient gel electrophoresis, terminal restriction fragment length polymorphism, and next-generation sequencing. The most abundant phylum for both treatments was Ascomycota, followed by Basidiomycota. The application of SMS and CM increased the abundance of fungi, including Tremellomycetes and Pezizomycetes for the SMS additive, while the Mortierellomycetes, Pezizomycetes, and Leotiomycetes levels increased after CM addition. SMS and CM beneficially reduced the relative abundance of several operational taxonomic units (OTUs) which are potential crop pathogens. The results provide a novel insight into the fungal community associated with organic additives, which should be beneficial in the task of managing the soil mycobiome as well as crop protection and productivity. Full article

(This article belongs to the Special Issue Sustainable Crop Production Protects the Quality of Soil and Plant Raw Materials)

► Show Figures

Figure 1

23 pages, 5119 KiB

Open AccessEditor’s ChoiceReview

Constitutive and Induced Salt Tolerance Mechanisms and Potential Uses of Limonium Mill. Species

by Sara González-Orenga, Marius-Nicusor Grigore, Monica Boscaiu and Oscar Vicente

Agronomy 2021, 11(3), 413; https://doi.org/10.3390/agronomy11030413 - 24 Feb 2021

Cited by 27 | Viewed by 4349

Abstract

Limonium is one of the most interesting and biodiverse genera of halophytes, with many species adapted to saline environments. Limonium species have a promising potential as cultivated minor crops as many have ornamental value, or are already used as medicinal plants. Other species [...] Read more.

Limonium is one of the most interesting and biodiverse genera of halophytes, with many species adapted to saline environments. Limonium species have a promising potential as cultivated minor crops as many have ornamental value, or are already used as medicinal plants. Other species are marketed as gourmet food or can be used for decontamination of polluted soils. Design and implementation of specific breeding programmes are needed to fully realise this potential, based on the vast genetic variation and high stress tolerance of wild species within the genus. Most Limonium species are halophytes, but many are also resistant to drought, especially those from the Mediterranean and other arid regions. Such species constitute attractive models for basic research on the mechanisms of stress tolerance, both constitutive and induced. As typical recretohalopyhtes, with excretive salt glands, Limonium species possess remarkable morpho-anatomical traits. Salt tolerance in this genus relies also on ion accumulation in the leaves, the concomitant use of diverse osmolytes for osmotic adjustment, and the activation of efficient antioxidant systems. Full article

(This article belongs to the Special Issue Physiology of Halophytes and Their Potential)

► Show Figures

Figure 1

17 pages, 2553 KiB

Open AccessEditor’s ChoiceArticle

Cladosporium sp. Isolate as Fungal Plant Growth Promoting Agent

by Iuliana Răut, Mariana Călin, Luiza Capră, Ana-Maria Gurban, Mihaela Doni, Nicoleta Radu and Luiza Jecu

Agronomy 2021, 11(2), 392; https://doi.org/10.3390/agronomy11020392 - 23 Feb 2021

Cited by 36 | Viewed by 8501

Abstract

Cladosporium species are active in protecting plants against different biotic and abiotic stresses. Since these species produced a wide range of secondary metabolites responsible for the adaptation to new habitats, plant health and performance, they are of great interest, especially for biostimulants in [...] Read more.

Cladosporium species are active in protecting plants against different biotic and abiotic stresses. Since these species produced a wide range of secondary metabolites responsible for the adaptation to new habitats, plant health and performance, they are of great interest, especially for biostimulants in agriculture. Cladosporium sp. produces protein hydrolysates (PHs), a class of biostimulants, by cultivation on medium with keratin wastes (feathers) as carbon and energy sources. The aim of this study was to select a Cladosporium isolate with potential to be used as plant growth promoting agent. The characteristics of Cladosporium isolates as plants biostimulants were evaluated through several tests, such as: antagonism versus plants pathogens, effect on plant growth of secreted volatiles produced by isolates, secretion of hydrolytic enzymes, production of 3-indole acetic acid, zinc and phosphorous solubilization, capacity to promote tomato seedlings growth (pot experiments). Cladosporium isolate T2 presented positive results to all tests. Encouraging results were obtained treating tomato seedlings with PHs from isolate Cladosporium T2 cultured on medium supplemented with 1% (w/w) chicken feathers, for which growth parameters, such as stem weight, stem height, and root weight were significantly higher by 65%, 32%, and 55%, respectively, compared to those treated with water. Full article

(This article belongs to the Special Issue Effects of Biostimulants and Bioeffectors on Plant Growth)

► Show Figures

Figure 1

15 pages, 1025 KiB

Open AccessEditor’s ChoiceArticle

Ghanaian Cocoa (Theobroma cacao L.) Bean Shells Coproducts: Effect of Particle Size on Chemical Composition, Bioactive Compound Content and Antioxidant Activity

by Carmen Botella-Martínez, Raquel Lucas-Gonzalez, Carmen Ballester-Costa, José Ángel Pérez-Álvarez, Juana Fernández-López, Johannes Delgado-Ospina, Clemencia Chaves-López and Manuel Viuda-Martos

Agronomy 2021, 11(2), 401; https://doi.org/10.3390/agronomy11020401 - 23 Feb 2021

Cited by 33 | Viewed by 6286

Abstract

The worldwide cocoa bean shell (CBS) generation is estimated at around 900,000 tons. In their composition, this coproduct showed several bioactive compounds like methylxanthines or polyphenolic compounds. Thus, the aim of this work was to investigate the effects of different particle sizes on [...] Read more.

The worldwide cocoa bean shell (CBS) generation is estimated at around 900,000 tons. In their composition, this coproduct showed several bioactive compounds like methylxanthines or polyphenolic compounds. Thus, the aim of this work was to investigate the effects of different particle sizes on the chemical composition, physico-chemical, bioactive compounds content, and antioxidant properties of flours obtained from cocoa (Theobroma cacao L.) bean shells. The flours obtained from CBS with different particle sizes had high content of dietary fiber (61.18–65.58 g/100 g). The polyphenolic profile identified seven compounds being epicatechin and catechin (values ranged 4.56–6.33 and 2.11–4.56 mg/g, respectively) as the most abundant compounds. Additionally, the methylxanthines theobromine and caffeine were quantified with values ranging from 7.12 to 12.77 and 4.02 to 6.13 mg/g, respectively. For the fatty acid profile, the principal compounds identified were oleic, stearic and palmitic acids. CBS had antioxidant capacity with all methods assayed. For DPPH, ABTS and FRAP assays values ranged between 2.35–5.53, 3.39–11.55, and 3.84–7.62 mg Trolox equivalents/g sample, respectively. This study suggests that cocoa bean shells may constitute a valuable coproduct for the food industry due to its high content in valuable bioactive compounds. Full article

(This article belongs to the Special Issue Potential Strategies for Adding Value of Mediterranean and Exotic Fruits and Vegetables ByProducts)

► Show Figures

Graphical abstract

18 pages, 1181 KiB

Open AccessEditor’s ChoiceArticle

Morphophysiology, Productivity and Quality of Soybean (Glycine max (L.) Merr.) cv. Merlin in Response to Row Spacing and Seeding Systems

by Marta Jańczak-Pieniążek, Jan Buczek, Dorota Bobrecka-Jamro, Ewa Szpunar-Krok, Renata Tobiasz-Salach and Wacław Jarecki

Agronomy 2021, 11(2), 403; https://doi.org/10.3390/agronomy11020403 - 23 Feb 2021

Cited by 18 | Viewed by 3683

Abstract

The appropriate row spacing and sowing density of soybeans are the basic non-input and pro-environmental agrotechnical factors. The optimal spacing of plants in the field can be crucial in terms of reducing competition between plants for water, nutrients and light, which is particularly [...] Read more.

The appropriate row spacing and sowing density of soybeans are the basic non-input and pro-environmental agrotechnical factors. The optimal spacing of plants in the field can be crucial in terms of reducing competition between plants for water, nutrients and light, which is particularly important for photosynthesis and maximizes the use of environmental resources. The field experiment was carried out in the years 2017–2019 at the Experimental Station for Cultivar Assessment in Przecław, Poland, on Merlin cv. soybean plants. The experimental factors were: row spacing of 15 and 30 cm and the sowing density of 70, 90 and 110 pcs. m⁻². During the research, the influence of row spacing and sowing density on yielding, seed quality, plant morphological features, nodulation and physiological processes in plants was assessed. The obtained soybean seed yield was not influenced by the experimental factors, but only by the weather conditions prevailing in the research years. The smaller row spacing and sowing density of 15/70 and 30/70 resulted in an increase in the parameters of the yield structure, the number and dry weight of root nodules, as well as the parameters of chlorophyll fluorescence (F_v/F_m, F_v/F₀ and PI). Greater plant density per area unit resulted in low yield structure parameters, lower number and dry weight of nodules, poorer parameters of chlorophyll fluorescence and higher protein content in seeds. With the increased sowing density, the plants were higher, the 1st. pod was placed higher and an LAI value was also higher. Full article

(This article belongs to the Special Issue Soybean Breeding, Agronomic Practices, and Production Systems)

► Show Figures

Figure 1

18 pages, 6813 KiB

Open AccessEditor’s ChoiceArticle

Impact of Integrated Agronomic Practices on Soil Fertility and Respiration on the Indo-Gangetic Plain of North India

by Rama Kant Dubey, Pradeep Kumar Dubey, Rajan Chaurasia, Ch Srinivasa Rao and Purushothaman Chirakkuzhyil Abhilash

Agronomy 2021, 11(2), 402; https://doi.org/10.3390/agronomy11020402 - 23 Feb 2021

Cited by 18 | Viewed by 3820

Abstract

Global agricultural production is accountable for the emission of ~30% of greenhouse gases. Therefore, the wide-scale adoptions of low-input, soil-friendly, and resource-conserving agronomic practices are imperative for the ‘planet healthy food production’ and also for reducing the carbon emissions from agricultural soil. In [...] Read more.

Global agricultural production is accountable for the emission of ~30% of greenhouse gases. Therefore, the wide-scale adoptions of low-input, soil-friendly, and resource-conserving agronomic practices are imperative for the ‘planet healthy food production’ and also for reducing the carbon emissions from agricultural soil. In this context, the present study aimed to analyze the impacts of integrated agronomic interventions i.e., the application of arbuscular mycorrhizal fungi (AMF) + reduced tillage (RT), biochar + RT, and AMF + biochar + RT, on spatiotemporal variations in soil-quality and soil-sustainability indicators, including microbial and soil respiration, in the Indo-Gangetic Plain (IGP) of North India. For this, field experiments on the above-mentioned agronomic interventions were employed using three different staple crops (Zea mays, Vigna mungo, and Brassica juncea) growing in three different agro-climatic zones of IGP (Varanasi, Sultanpur, and Gorakhpur) in a randomized block design. Periodic data collection was done to analyze the changes in physiochemical, biological, and biochemical properties of the soil, and statistical analyses were done accordingly. Irrespective of the sites, the experimental results proved that the integrated application of AMF + biochar + RT in V. mungo resulted in the highest soil organic carbon (i.e., 135% increment over the control) and microbial biomass carbon (24%), whereas the same application (i.e., AMF + biochar + RT) in Z. mays had the maximum reduction in microbial (32%) and soil (44%) respiration. On the other hand, enhanced occurrence of glomalin activity (98%) was noted in Z. mays cropping for all the sites. Significant negative correlation between soil respiration and glomalin activity under AMF + biochar + RT (−0.85), AMF + RT (−0.82), and biochar + RT (−0.62) was an indication of glomalin’s role in the reduced rate of soil respiration. The research results proved that the combined application of AMF + biochar + RT was the best practice for enhancing soil quality while reducing respiration. Therefore, the development of suitable packages of integrated agronomic practices is essential for agricultural sustainability. Full article

(This article belongs to the Section Farming Sustainability)

► Show Figures

Figure 1

15 pages, 4204 KiB

Open AccessEditor’s ChoiceArticle

Novel Bacillus cereus Strain, ALT1, Enhance Growth and Strengthens the Antioxidant System of Soybean under Cadmium Stress

by Atlaw Anbelu Sahile, Muhammad Aaqil Khan, Muhammad Hamayun, Muhammad Imran, Sang-Mo Kang and In-Jung Lee

Agronomy 2021, 11(2), 404; https://doi.org/10.3390/agronomy11020404 - 23 Feb 2021

Cited by 27 | Viewed by 4031

Abstract

Cadmium stress significantly decreases agricultural productivity worldwide. Plant growth-promoting rhizobacteria (PGPR) are eco-friendly and inexpensive tool for mitigating heavy metal stress in crops. We isolated rhizospheric bacteria and screened them for various plant growth-promoting (PGP) traits as well as Cd tolerance. Only 6 [...] Read more.

Cadmium stress significantly decreases agricultural productivity worldwide. Plant growth-promoting rhizobacteria (PGPR) are eco-friendly and inexpensive tool for mitigating heavy metal stress in crops. We isolated rhizospheric bacteria and screened them for various plant growth-promoting (PGP) traits as well as Cd tolerance. Only 6 bacterial isolates out of 55 assessed showed multiple PGP traits in response to different Cd concentrations. The Bacillus cereus ALT1 strain showed high tolerance to increased Cd amounts in the culture medium, while secreting indole-3-acetic acid (IAA) and organic acids into the culture medium. High Cd concentrations (0.7 mM, 1.4 mM, and 2.1 mM) reduced soybean shoot and root length, root/shoot fresh and dry weight, as well as chlorophyll content; however, inoculation with the bacterial isolate ALT1 mitigated Cd stress and enhanced both soybean growth parameters and chlorophyll content. It also decreased abscisic acid (ABA) amounts, enhanced salicylic acid (SA) production, and promoted antioxidant response by increasing total proteins (TP) and superoxide dismutase (SOD), while decreasing glutathione (GSH) content, lipid peroxidation (LPO), peroxidase (POD), superoxide anion (SOA), and polyphenol oxidase (PPO) in soybean plants. In addition, inductively coupled plasma mass spectrometry (ICP-MS) showed that soybean plants treated with the bacterial isolate ALT1 enhanced K uptake and decreased Cd amounts in comparison to control plants. The present study reveals that Cd-tolerant bacterial isolate ALT1 can alleviate Cd toxicity on plants by increasing their growth, thus imposing itself as an eco-friendly bio-fertilizer under Cd stress. Full article

► Show Figures

Graphical abstract

15 pages, 2011 KiB

Open AccessEditor’s ChoiceArticle

Cover Crop Contributions to Improve the Soil Nitrogen and Carbon Sequestration in Almond Orchards (SW Spain)

by Miguel A. Repullo-Ruibérriz de Torres, Manuel Moreno-García, Rafaela Ordóñez-Fernández, Antonio Rodríguez-Lizana, Belén Cárceles Rodríguez, Iván Francisco García-Tejero, Víctor Hugo Durán Zuazo and Rosa M. Carbonell-Bojollo

Agronomy 2021, 11(2), 387; https://doi.org/10.3390/agronomy11020387 - 22 Feb 2021

Cited by 21 | Viewed by 5053

Abstract

Almond (Prunus dulcis Mill. [D.A. Webb]) is the third most widely spread crop in Spain and has traditionally been cultivated in marginal areas and shallow soils under rainfed conditions. However, it recently has been progressively introduced in flat irrigated areas. The implementation [...] Read more.

Almond (Prunus dulcis Mill. [D.A. Webb]) is the third most widely spread crop in Spain and has traditionally been cultivated in marginal areas and shallow soils under rainfed conditions. However, it recently has been progressively introduced in flat irrigated areas. The implementation of cover crops in the inter-rows of woody crops has been proven as a suitable strategy to reduce the runoff and soil erosion but they also can boost soil quality and health. A field experiment was conducted during two-monitoring seasons to examine the soil nitrogen and carbon sequestration potential of three seeded cover crops [barley (Hordeum vulgare L.), hairy vetch (Vicia villosa Roth), and a mixture of 65% barley and 35% vetch] and a control of spontaneous flora in irrigated almond orchards (SW Spain). Here, we show that barley provided the highest biomass amount, followed by mixture covers, vetch, and the control treatment. Also, vetch covered the soil faster in the growing stage, but its residues were decomposed easier than barley and mixture treatments during the decomposition period after mowing, providing less soil protection when the risk of water erosion with autumn rainfall is high. On the other hand, vetch improved soil nitrate content by over 35% with respect to barley and mixture treatments at 0–20 cm soil depth throughout the studied period. In addition, a greater carbon input to the soil was determined in the barley plot. That is, the mixture and barley cover crops had higher potential for carbon sequestration, augmenting the soil organic carbon by more than 1.0 Mg ha⁻¹ during the study period. Thus, taking into consideration the findings of the present experiment, the establishment of a seeded cover crop would be more advisable than spontaneous flora to mitigate soil erosion, enhancing soil fertility and carbon sequestration in irrigated almond plantations in Mediterranean semi-arid regions. Full article

(This article belongs to the Special Issue Conservation Agriculture as a Key Challenge for Sustainable Agroecosystems in Climate Change Mitigation and Adaptation)

► Show Figures

Figure 1

12 pages, 1049 KiB

Open AccessEditor’s ChoiceArticle

Zinc Uptake by Plants as Affected by Fertilization with Zn Sulfate, Phosphorus Availability, and Soil Properties

by Ramiro Recena, Ana M. García-López and Antonio Delgado

Agronomy 2021, 11(2), 390; https://doi.org/10.3390/agronomy11020390 - 22 Feb 2021

Cited by 48 | Viewed by 4721

Abstract

Zinc (Zn) deficiency constrains crop yield and quality, but soil factors influencing Zn availability to plants and reactions of applied Zn fertilizer are not fully understood. This work is aimed at studying Zn availability in soil and the use efficiency of Zn fertilizers [...] Read more.

Zinc (Zn) deficiency constrains crop yield and quality, but soil factors influencing Zn availability to plants and reactions of applied Zn fertilizer are not fully understood. This work is aimed at studying Zn availability in soil and the use efficiency of Zn fertilizers by plants as affected by soil properties and particularly by soil available P. We performed a pot experiment involving four consecutive crops fertilized with Zn sulfate using 36 soils. The cumulative Zn uptake and dry matter yield in the four crops increased with increased initial diethylenetriamine pentaacetic acid extraction of Zn (DTPA-Zn) (R² = 0.75 and R² = 0.61; p < 0.001). The initial DTPA-Zn increased with increased Olsen P (R² = 0.41; p < 0.001) and with increased ratio of Fe in poorly crystalline to Fe in crystalline oxides (R² = 0.58; p < 0.001). DTPA-Zn decreased with increased cumulative Zn uptake, but not in soils with DTPA-Zn < 0.5 mg kg⁻¹. Overall, the available Zn is more relevant in explaining Zn uptake by plants than applied Zn sulfate. However, in Zn-deficient soils, Zn fertilizer explained most of the Zn uptake by crops. Poorly crystalline Fe oxides and P availability exerted a positive role on Zn availability to plants in soil. Full article

(This article belongs to the Special Issue Phosphorus and Micronutrient Interactions in Soils)

► Show Figures

Figure 1

17 pages, 765 KiB

Open AccessEditor’s ChoiceArticle

Species Interactions and Nitrogen Use during Early Intercropping of Intermediate Wheatgrass with a White Clover Service Crop

by Shoujiao Li, Erik Steen Jensen, Nan Liu, Yingjun Zhang and Linda-Maria Dimitrova Mårtensson

Agronomy 2021, 11(2), 388; https://doi.org/10.3390/agronomy11020388 - 22 Feb 2021

Cited by 11 | Viewed by 3134

Abstract

Perennial grain crops intercropped with legumes are expected to use nitrogen (N) resources efficiently. A pot experiment using the ¹⁵N isotope dilution method demonstrated interspecific competition and use of N from the soil and N₂ fixation in intermediate wheatgrass (Thinopyrum [...] Read more.

Perennial grain crops intercropped with legumes are expected to use nitrogen (N) resources efficiently. A pot experiment using the ¹⁵N isotope dilution method demonstrated interspecific competition and use of N from the soil and N₂ fixation in intermediate wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey, IWG) and white clover (Trifolium repens L., WC) intercrops at five species-relative frequencies and four levels of inorganic N fertilizer in a replacement series design. The proportion of N in WC derived from the atmosphere increased from 39.7% in a sole crop to 70.9% when intercropped with IWG, and 10.1% N in IWG transferred from WC. Intermediate wheatgrass showed high fitness with maintained high total dry matter production at low relative frequencies. Decreasing IWG-relative frequency only increased dry matter and N accumulation of WC, resulting in increased amounts of N₂ fixed. Increased levels of N fertilization increased the proportion of N acquired from the fertilizer in IWG and WC but decreased the N fixed by WC and N absorbed by IWG from the soil. Our study indicates that WC supply sufficient fixed N₂ for IWG intercrop biomass yields under appropriate levels of soil N fertility and species-relative frequencies. Full article

(This article belongs to the Special Issue Assessing Breeding Technologies and Ecosystem Services in Perennial Agriculture and Novel Farming Systems)

► Show Figures

Figure 1

42 pages, 1862 KiB

Open AccessEditor’s ChoiceArticle

Pluralistic Seed System Development: A Path to Seed Security?

by Teshome Hunduma Mulesa, Sarah Paule Dalle, Clifton Makate, Ruth Haug and Ola Tveitereid Westengen

Agronomy 2021, 11(2), 372; https://doi.org/10.3390/agronomy11020372 - 20 Feb 2021

Cited by 35 | Viewed by 10198

Abstract

Seed security is central to crop production for smallholder farmers in developing countries, but it remains understudied in relation to long-term seed sector development. Here, we compare seed systems in two districts of Central Ethiopia characterized by subsistence-oriented teff cultivation and commercially oriented [...] Read more.

Seed security is central to crop production for smallholder farmers in developing countries, but it remains understudied in relation to long-term seed sector development. Here, we compare seed systems in two districts of Central Ethiopia characterized by subsistence-oriented teff cultivation and commercially oriented wheat production and relate this to the country’s pluralistic seed system development strategy (PSSDS). Our analysis is based on quantitative and qualitative information from a household survey and focus group discussions with farmers, as well as document review and key informant interviews with actors that make up the seed sector in the study sites. Farmers in both districts used a range of seed sources but primarily obtained their seeds from informal sources. Evidence of seed insecurity was found in both districts, as apparent from discrepancies between what the seed farmers say they prefer and those they actually use, limited availability of improved varieties and especially certified seeds of these, challenges with seed quality from some sources, and differentiated access to preferred seed and information according to sex, age and wealth. We find that the interventions prioritized in the PSSDS address most of the seed security challenges and seed system dysfunctions identified, but implementation lags, particularly for the informal seed system, which is largely neglected by government programs. The intermediate system shows promise, but while some improvements have been made in the formal system, vested political, organizational, and economic interests within key institutions represent major obstacles that must be overcome to achieve truly integrative and inclusive seed sector development. Full article

(This article belongs to the Special Issue The Role of Policies in Plant Breeding—Rights and Obligations)

► Show Figures

Figure 1

28 pages, 2265 KiB

Open AccessEditor’s ChoiceReview

Modern Approaches for the Genetic Improvement of Rice, Wheat and Maize for Abiotic Constraints-Related Traits: A Comparative Overview

by Elena Benavente and Estela Giménez

Agronomy 2021, 11(2), 376; https://doi.org/10.3390/agronomy11020376 - 20 Feb 2021

Cited by 21 | Viewed by 7258

Abstract

After a basic description of the different sets of genetic tools and genomic approaches most relevant for modern crop breeding (e. g., QTL mapping, GWAS and genomic selection; transcriptomics, qPCR and RNA-seq; transgenesis and gene editing), this review paper describes their history and [...] Read more.

After a basic description of the different sets of genetic tools and genomic approaches most relevant for modern crop breeding (e. g., QTL mapping, GWAS and genomic selection; transcriptomics, qPCR and RNA-seq; transgenesis and gene editing), this review paper describes their history and the main achievements in rice, wheat and maize research, with a further focus on crop traits related to the improvement of plant responses to face major abiotic constrains, including nutritional limitations, drought and heat tolerance, and nitrogen-use efficiency (NUE). Remarkable differences have been evidenced regarding the timing and degree of development of some genetic approaches among these major crops. The underlying reasons related to their distinct genome complexity, are also considered. Based on bibliographic records, drought tolerance and related topics (i.e., water-use efficiency) are by far the most abundantly addressed by molecular tools among the breeding objectives considered. Heat tolerance is usually more relevant than NUE in rice and wheat, while the opposite is true for maize. Full article

(This article belongs to the Special Issue Molecular Genetics, Genomics and Biotechnology of Crop Plants Breeding - Series Ⅱ)

► Show Figures

Figure 1

27 pages, 1689 KiB

Open AccessEditor’s ChoiceReview

Using Regulatory Flexibility to Address Market Informality in Seed Systems: A Global Study

by Katrin Kuhlmann and Bhramar Dey

Agronomy 2021, 11(2), 377; https://doi.org/10.3390/agronomy11020377 - 20 Feb 2021

Cited by 26 | Viewed by 6577

Abstract

Seed rules and regulations determine who can produce and sell seeds, which varieties will be available in the market, the quality of seed for sale, and where seed can be bought and sold. The legal and regulatory environment for seed impacts all stakeholders, [...] Read more.

Seed rules and regulations determine who can produce and sell seeds, which varieties will be available in the market, the quality of seed for sale, and where seed can be bought and sold. The legal and regulatory environment for seed impacts all stakeholders, including those in the informal sector, through shaping who can participate in the market and the quality and diversity of seed available. This paper addresses a gap in the current literature regarding the role of law and regulation in linking the informal and formal seed sectors and creating more inclusive and better governed seed systems. Drawing upon insights from the literature, global case studies, key expert consultations, and a methodology on the design and implementation of law and regulation, we present a framework that evaluates how regulatory flexibility can be built into seed systems to address farmers’ needs and engage stakeholders of all sizes. Our study focuses on two key dimensions: extending market frontiers and liberalizing seed quality control mechanisms. We find that flexible regulatory approaches and practices play a central role in building bridges between formal and informal seed systems, guaranteeing quality seed in the market, and encouraging market entry for high-quality traditional and farmer-preferred varieties. Full article

(This article belongs to the Special Issue The Role of Policies in Plant Breeding—Rights and Obligations)

► Show Figures

Figure 1

20 pages, 1070 KiB

Open AccessEditor’s ChoiceArticle

Nitrogen, Phosphorus, and Potassium Adsorption and Desorption Improvement and Soil Buffering Capacity Using Clinoptilolite Zeolite

by Perumal Palanivell, Osumanu Haruna Ahmed, Latifah Omar and Nik Muhamad Abdul Majid

Agronomy 2021, 11(2), 379; https://doi.org/10.3390/agronomy11020379 - 20 Feb 2021

Cited by 20 | Viewed by 3765

Abstract

The physical and chemical properties of clinoptilolite zeolite can be used to enhance soil nutrient availability for optimum crop use. Amending nitrogen, phosphorus, and potassium fertilizers with clinoptilolite zeolite could create a pool of negative charges to retain and release nutrients timely for [...] Read more.

The physical and chemical properties of clinoptilolite zeolite can be used to enhance soil nutrient availability for optimum crop use. Amending nitrogen, phosphorus, and potassium fertilizers with clinoptilolite zeolite could create a pool of negative charges to retain and release nutrients timely for crop use. Thus, we used clinoptilolite zeolite to enhance Typic Paleudults sorption (adsorption and desorption) of nitrogen, phosphorus, potassium, and this soil’s pH buffering capacity. The treatments evaluated were: (i) 250 g soil alone, (ii) 20 g clinoptilolite zeolite alone, (iii) 250 g soil + 20 g clinoptilolite zeolite, (iv) 250 g soil + 40 g clinoptilolite zeolite, and (v) 250 g soil + 60 g clinoptilolite zeolite. Clinoptilolite zeolite increased soil nitrogen and potassium adsorption, nitrogen desorption, and soil pH. Moreover, ability of the soil to resist drastic change in pH (pH buffering capacity) was improved. Additionally, phosphorus adsorption and desorption of phosphorus and potassium were reduced. Higher potassium adsorption with lower potassium desorption suggests that the clinoptilolite zeolite sorbs potassium effectively. The clinoptilolite zeolite nitrogen, phosphorus, and potassium contributed to the reduction in the adsorption these nutrients. The clinoptilolite zeolite improved nitrogen, phosphorus, and potassium availability and soil buffering capacity to prevent these nutrients from being fixed or lost through for example, leaching. Therefore, clinoptilolite zeolite application could contribute to improved use of nitrogen, phosphorus, and potassium fertilizers to prevent soil, air, and water pollution. Additionally, our intervention could improve nitrogen, phosphorus, and potassium use efficiency. Full article

► Show Figures

Figure 1

18 pages, 4744 KiB

Open AccessEditor’s ChoiceArticle

Biostimulant Activity of Azotobacter chroococcum and Trichoderma harzianum in Durum Wheat under Water and Nitrogen Deficiency

by Silvia Silletti, Emilio Di Stasio, Michael James Van Oosten, Valeria Ventorino, Olimpia Pepe, Mauro Napolitano, Roberta Marra, Sheridan Lois Woo, Valerio Cirillo and Albino Maggio

Agronomy 2021, 11(2), 380; https://doi.org/10.3390/agronomy11020380 - 20 Feb 2021

Cited by 30 | Viewed by 4433

Abstract

Biostimulants hold great potential for developing integrated sustainable agriculture systems. The rhizobacteria Azotobacter chroococcum strain 76A and the fungus Trichoderma harzianum strain T22, with demonstrated biostimulant activity in previous systems, were evaluated in Triticum durum cv Creso for their ability to enhance growth [...] Read more.

Biostimulants hold great potential for developing integrated sustainable agriculture systems. The rhizobacteria Azotobacter chroococcum strain 76A and the fungus Trichoderma harzianum strain T22, with demonstrated biostimulant activity in previous systems, were evaluated in Triticum durum cv Creso for their ability to enhance growth and tolerance to drought stress. Growth and drought tolerance were evaluated in conditions of low and high soil nitrogen, with two levels of water stress. T. harzianum increased plant growth (+16%) under control conditions and tolerance to moderate drought stress (+52%) under optimal fertilization, while A. chroococcum conferred a growth penalty (−28%) in well-watered conditions under suboptimal fertilization and increased tolerance only under extreme drought stress (+15%). This growth penalty was ameliorated by nitrogen fertilization. T. harzianum abundance was found to be positively correlated to extreme soil drying, whereas A. chroococcum-induced tolerance was dependent on soil nitrogen availability. These results indicate that while biostimulants may enhance growth and stress tolerance, nutrient availability soil and environmental conditions heavily influence these responses. These interactions should be considered when designing biostimulant products targeted to specific cultural conditions. Full article

► Show Figures

Figure 1

22 pages, 5054 KiB

Open AccessEditor’s ChoiceArticle

Investigating Combined Drought- and Heat Stress Effects in Wheat under Controlled Conditions by Dynamic Image-Based Phenotyping

by Lamis Osama Anwar Abdelhakim, Eva Rosenqvist, Bernd Wollenweber, Ioannis Spyroglou, Carl-Otto Ottosen and Klára Panzarová

Agronomy 2021, 11(2), 364; https://doi.org/10.3390/agronomy11020364 - 18 Feb 2021

Cited by 24 | Viewed by 5172

Abstract

As drought and heat stress are major challenges for crop productivity under future climate changes, tolerant cultivars are highly in demand. This study investigated the potential of existing Nordic wheat genotypes to resist unfavorable conditions. Four genotypes were selected based on their heat [...] Read more.

As drought and heat stress are major challenges for crop productivity under future climate changes, tolerant cultivars are highly in demand. This study investigated the potential of existing Nordic wheat genotypes to resist unfavorable conditions. Four genotypes were selected based on their heat sensitivity (heat-sensitive: LM19, SF1; heat-tolerant: LM62, NS3). At the tillering stage, the plants were subjected to four treatments under controlled conditions: control, drought, heat and combined drought and heat stress. The morpho-physiological performance was quantified during the early and late phase of stress, as well as the recovery phase. We applied an integrative image-based phenotyping approach monitoring plant growth dynamics by structural Red Green Blue (RGB) imaging, photosynthetic performance by chlorophyll fluorescence imaging and transpiration efficiency by thermal infrared imaging. The results demonstrated that the selected genotypes were moderately affected in their photosynthetic efficiency and growth under drought stress, whereas heat and combined stress caused rapid reductions in photosynthesis and growth. Furthermore, drought stress had a major impact on canopy temperature. The NS3 genotype was the most robust genotype, as indicated by its improved response under all stress treatments due to its relatively small biomass. However, the genotypes showed different tolerance to individual and combined stress. Full article

(This article belongs to the Special Issue Phenotyping for Resilient and Sustainable Crops)

► Show Figures

Figure 1

17 pages, 2797 KiB

Open AccessEditor’s ChoiceArticle

Genotype × Environment Interaction of Yield and Grain Quality Traits of Maize Hybrids in Greece

by Nikolaos Katsenios, Panagiotis Sparangis, Sofia Chanioti, Marianna Giannoglou, Dimitris Leonidakis, Miltiadis V. Christopoulos, George Katsaros and Aspasia Efthimiadou

Agronomy 2021, 11(2), 357; https://doi.org/10.3390/agronomy11020357 - 17 Feb 2021

Cited by 24 | Viewed by 4279

Abstract

The interaction of genotype by the environment is very common in multi-environment trials of maize hybrids. This study evaluates the quantity and the quality of grain production and the stability of four maize genotypes in a field experiment that was conducted in five [...] Read more.

The interaction of genotype by the environment is very common in multi-environment trials of maize hybrids. This study evaluates the quantity and the quality of grain production and the stability of four maize genotypes in a field experiment that was conducted in five different locations for two years. In order to make a reliable evaluation of the performance of genotypes in the environments, principal components analysis (PCA) was used to investigate the correlation of the yield, soil properties and quality characteristics, while the additive main effects and multiplicative interaction (AMMI) analysis detected the narrow adaptations of genotypes at specific mega-environments. For the yield, AMMI analysis indicated that a group of five environments (ENV1, ENV8, ENV6 ENV10 and ENV9) gave higher yields than the mean value and at the same time had low first interaction principal components axis (IPC1) scores, indicating small interactions. Regarding protein and fiber contents, ENV1 and ENV2, gave the highest values and this could be attributed to the high concentration rates of nutrients like Mg, Ca and the soil texture (C). Specifically for the protein, the results of the analysis indicated that certain environment would provide more protein content, so in order to obtain higher grain protein, growers should grow in certain locations in order to improve the content of this quality characteristic, certain genotypes should be used in certain environments. Full article

(This article belongs to the Special Issue Sustainable Agricultural Practices—Impact on Soil Quality and Plant Health)

► Show Figures

Figure 1

11 pages, 262 KiB

Open AccessEditor’s ChoiceArticle

Use of Biochar-Compost for Phosphorus Availability to Maize in a Concretionary Ferric Lixisol in Northern GHANA

by Nasirudeen Sulemana, Eric K. Nartey, Mark K. Abekoe, Thomas A. Adjadeh and Daniel A. Darko

Agronomy 2021, 11(2), 359; https://doi.org/10.3390/agronomy11020359 - 17 Feb 2021

Cited by 11 | Viewed by 4394

Abstract

A pot experiment was conducted to investigate the effect of biochar-compost on availability of P for maize cultivation in a concretionary Lixisol of northern Ghana and residual soil characteristics thereof. Sawdust biochar was co-composted with kitchen waste and cow dung in various proportions. [...] Read more.

A pot experiment was conducted to investigate the effect of biochar-compost on availability of P for maize cultivation in a concretionary Lixisol of northern Ghana and residual soil characteristics thereof. Sawdust biochar was co-composted with kitchen waste and cow dung in various proportions. Four biochar-composts were selected based on their superior carbon and available P content, lower pH, and electrical conductivity (EC). These were amended to attain the standard phosphorus requirement (SPR) and half the SPR of the Lixisol. Triple superphosphate and (NH₄)₂ SO₄ were, respectively, applied as inorganic fertilizer to meet the SPR and the average total nitrogen of the selected biochar-compost treatments. A control without any soil amendment was included. Maize was grown to tasseling (eight weeks) and shoot dry matter and P uptake determined. A 2.71 to 3.71-fold increase in P uptake led to a 1.51 to 2.33-fold increase in shoot dry matter in biochar-compost-amended soils over the control. Residual soil C, pH, and total and available P in the biochar-compost-amended soils were enhanced. Biochar-composts at half the SPR level produced maize with higher shoot dry matter than the equivalent inorganic amendment at full SPR. Full article

(This article belongs to the Special Issue Managing Nutrient Balances in Agriculture - Agronomy, Animal Manure and the Circularity of Nitrogen and Phosphorus)

14 pages, 4913 KiB

Open AccessEditor’s ChoiceArticle

Salinity Stress as an Elicitor for Phytochemicals and Minerals Accumulation in Selected Leafy Vegetables of Brassicaceae

by Dunja Šamec, Ida Linić and Branka Salopek-Sondi

Agronomy 2021, 11(2), 361; https://doi.org/10.3390/agronomy11020361 - 17 Feb 2021

Cited by 43 | Viewed by 4534

Abstract

The potential role of NaCl (50–200 mM) as an eustressor for the accumulation of health promoting phytochemicals and maintaining the homeostasis of macro- and micro-elements in three, hydroponically grown Brassica leafy vegetables (Chinese cabbage, white cabbage, and kale) was investigated. Considering K⁺ [...] Read more.

The potential role of NaCl (50–200 mM) as an eustressor for the accumulation of health promoting phytochemicals and maintaining the homeostasis of macro- and micro-elements in three, hydroponically grown Brassica leafy vegetables (Chinese cabbage, white cabbage, and kale) was investigated. Considering K⁺/Na⁺ ratio and proline contents as reliable stress markers, we confirmed more prominent stress status in Chinese cabbage followed by white cabbage and kale. Low to moderate salinity treatments (50 and 100 mM NaCl) caused an increase in most of the phenolic compounds in the analyzed Brassica leafy vegetables. Total glucosinolates were elicited by NaCl in a dose dependent manner. Salt treatment caused an increase in total chlorophylls but did not significantly affect carotenoid content. Furthermore, low to moderate treatments did not significantly disturb homeostasis of macro- and micro-elements, particularly in white cabbage and kale where the K level did not decrease significantly and Ca was even increased in white cabbage. We may conclude that salinity may elicit phytochemical accumulation in selecting vegetables grown on saline soils without undesirable disturbance in macro- and micro-elements homeostasis depending on salt concentration and species/varieties. This information may be of great importance in the selection of crops grown on saline soils. Full article

(This article belongs to the Special Issue How Plants Perceive Salt during the Irrigation)

► Show Figures

Figure 1

13 pages, 637 KiB

Open AccessEditor’s ChoiceArticle

Factors Affecting Sugar Accumulation and Fluxes in Warm- and Cool-Season Forages Grown in a Silvopastoral System

by Valens Niyigena, Amanda J. Ashworth, Christine Nieman, Mohan Acharya, Kenneth P. Coffey, Dirk Philipp, Lillian Meadors and Thomas J. Sauer

Agronomy 2021, 11(2), 354; https://doi.org/10.3390/agronomy11020354 - 16 Feb 2021

Cited by 15 | Viewed by 3100

Abstract

Forage management and environmental conditions affect water soluble carbohydrate (WSC) storage, and, in turn, influence ruminant forage utilization in silvopastoral systems. The objective was to determine effects of four dependent variables: forage species [(non-native, C₃ (orchardgrass (Dactylis glomerata L.)) and native [...] Read more.

Forage management and environmental conditions affect water soluble carbohydrate (WSC) storage, and, in turn, influence ruminant forage utilization in silvopastoral systems. The objective was to determine effects of four dependent variables: forage species [(non-native, C₃ (orchardgrass (Dactylis glomerata L.)) and native C₄ mix (8:1:1 big bluestem (Andropogon gerardii Vitman), little bluestem (Schizachyrium scoparium Michx. Nash) and indiangrass (Sorghastrum nutans L.))]; fertility (poultry litter and an unfertilized control); forage sampling date (mid-May, late-May, early-June, mid-June, and late-June); and hour of day (0800, 1100, 1400, and 1700 h) on WSC accumulation in a silvopasture. Concentrations of WSC (g kg DM⁻¹) were greater (p ≤ 0.05) for C₃ forages, with poultry litter not impacting WSC accumulation. Overall, WSC was greatest in mid-June, with the lowest WSC concentration observed at 0800 compared to 1100, 1400, and 1700 h (p ≤ 0.05). Therefore, harvesting forages later in the day resulted in greater WSC. A stepwise regression model indicated acid detergent fiber, ash, and forage P concentration were the best predictors (R₂ = 0.85, p ≤ 0.05) of forage WSC. These results may be useful in future studies aimed at explaining diurnal cattle grazing preference and optimum forage harvest timing in silvopastoral systems. Full article

(This article belongs to the Special Issue New Paradigms in Sustainable Forage-Livestock Production Systems)

► Show Figures

Figure 1

15 pages, 728 KiB

Open AccessEditor’s ChoiceArticle

Nutrient Supplementation Configures the Bioactive Profile and Production Characteristics of Three Brassica L. Microgreens Species Grown in Peat-Based Media

by Christophe El-Nakhel, Antonio Pannico, Giulia Graziani, Marios C. Kyriacou, Anna Gaspari, Alberto Ritieni, Stefania De Pascale and Youssef Rouphael

Agronomy 2021, 11(2), 346; https://doi.org/10.3390/agronomy11020346 - 15 Feb 2021

Cited by 40 | Viewed by 4594

Abstract

Brassica L. microgreens are a fresh microscale vegetable crop of high antioxidant value and naturally dense in nutrients without the intervention of biofortification or genetic engineering. A climate chamber experiment on peat-based substrate was set up to test microgreens growth and accumulation of [...] Read more.

Brassica L. microgreens are a fresh microscale vegetable crop of high antioxidant value and naturally dense in nutrients without the intervention of biofortification or genetic engineering. A climate chamber experiment on peat-based substrate was set up to test microgreens growth and accumulation of secondary metabolites in response to nutrient supplementation. Microgreens mineral content was analyzed through ion chromatography and total ascorbic acid through UV-Vis spectrophotometry, while carotenoids and phenolic acids were quantified by HPLC-DAD and UHPLC-HRMS, respectively. Brussels sprouts and cabbage yield was only reduced by 10%, while nitrate was reduced by 99% in the absence of nutrient supplementation. Rocket yield was prominently reduced by 47%, with a corresponding nitrate reduction of 118%. Brussels sprouts secondary metabolites were not improved by the absence of nutrient supplementation, whereas cabbage microgreens demonstrated a 30% increase in total ascorbic acid and a 12% increase in total anthocyanins. As for rocket, the absence of nutrient supplementation elicited an extensive increase in secondary metabolites, such as lutein (110%), β-carotene (30%), total ascorbic acid (58%) and total anthocyanins (20%), but caused a decrease in total phenolic acids. It is hereby demonstrated that growing microgreens on a commercial peat-based substrate without nutrient supplementation can be feasible for certain species. Moreover, it might elicit a species-dependent spike in bioactive secondary metabolites. Full article

(This article belongs to the Special Issue Sprouts, Microgreens and Edible Flowers as Novel Functional Foods)

► Show Figures

Figure 1

18 pages, 4100 KiB

Open AccessEditor’s ChoiceArticle

Evaluation of SEBS, METRIC-EEFlux, and QWaterModel Actual Evapotranspiration for a Mediterranean Cropping System in Southern Italy

by Zaibun Nisa, Muhammad Sarfraz Khan, Ajit Govind, Marco Marchetti, Bruno Lasserre, Enzo Magliulo and Antonio Manco

Agronomy 2021, 11(2), 345; https://doi.org/10.3390/agronomy11020345 - 15 Feb 2021

Cited by 16 | Viewed by 4562

Abstract

Remote sensing-based evapotranspiration (ET) models with various levels of sophistication have emerged recently with the possibilities of user-defined model calibrations. Their application for water resources management and climate studies from regional to global scale has been rapidly increasing, which makes it important to [...] Read more.

Remote sensing-based evapotranspiration (ET) models with various levels of sophistication have emerged recently with the possibilities of user-defined model calibrations. Their application for water resources management and climate studies from regional to global scale has been rapidly increasing, which makes it important to validate field scale ET in a complex crop assemblage before operational use. Based on in situ flux-tower measurements by the eddy-covariance (EC) system, this study tested three single-source energy balance models for estimating daily ET from fennel/maize/ryegrass-clover cropland rotations in a Mediterranean context in southern Italy. The sensitivity of three user-friendly ET models (SEBS, QWaterModel, and METRIC-EEFlux) with reference to the EC system over a center pivot irrigated cropland is discussed in detail. Results in terms of statistical indicators revealed that SEBS and METRIC-EEFlux showed reasonable agreements with measured ET (r² = 0.59_SEBS, RMSE = 0.71 mm day⁻¹; r² = 0.65_METRIC, RMSE = 1.13 mm day⁻¹) in terms of trends and magnitudes. At 30 m spatial resolution, both models were able to capture the in-field variations only during the maize development stage. The presence of spurious scan lines due to sensor defects in Landsat L7 ETM+ can contribute to the qualities of the METRIC-Efflux’s ET product. In our observation, the QWaterModel did not perform well and showed the weakest congruency (r² = 0.08_QWaterModel) with ground-based ET estimates. In a nutshell, the study evaluated these automated remote sensing-based ET estimations and suggested improvements in the context of a generic approach used in their underlying algorithm for robust ET retrievals in rotational cropland ecosystems. Full article

► Show Figures

Figure 1

14 pages, 2504 KiB

Open AccessEditor’s ChoiceArticle

Agronomic Comparisons of Heirloom and Modern Processing Tomato Genotypes Cultivated in Organic and Conventional Farming Systems

by Domenico Ronga, Federica Caradonia, Antonella Vitti and Enrico Francia

Agronomy 2021, 11(2), 349; https://doi.org/10.3390/agronomy11020349 - 15 Feb 2021

Cited by 5 | Viewed by 2623

Abstract

The yield and fruit quality of processing tomatoes (Solanum lycopersicum L.) have increased markedly over the past decades. The aim of this work was to assess the effects of the organic (OFS) and conventional farming systems (CFS) on the main agronomic parameters [...] Read more.

The yield and fruit quality of processing tomatoes (Solanum lycopersicum L.) have increased markedly over the past decades. The aim of this work was to assess the effects of the organic (OFS) and conventional farming systems (CFS) on the main agronomic parameters involved in processing tomato yield components and fruit quality traits of heirloom and modern genotypes. Marketable yield increased from heirloom to modern genotypes, both in OFS and in CFS, showing a difference of ≈20 t per hectare in favor of CFS. Total fruit yield (TY) was not improved from heirloom to modern assessed genotypes, and a difference of ≈35 t per hectare was observed in favor of CFS. In both farming systems, the highest marketable yield of modern genotypes was due to a higher number of fruits per plant, harvest index, nitrogen agronomic efficiency (NAE), and fruit water productivity. Moreover, the main growth parameters involved in the yield differences between OFS and CFS were the number of leaves per plant, the average fruit weight, the normalized difference vegetation index (NDVI), and NAE. It is noteworthy that fruit quality improvement in terms of color and brix per hectare was paralleled by a decrease of tomato pH in both farming systems. According to our results, we conclude that to reduce the current yield gap between OFS and CFS, agronomic and breeding efforts should be undertaken to increase leaf area index, fruit number per plant, and NAE for better genotype adaptation to organic farming systems. Full article

(This article belongs to the Special Issue Organic vs. Conventional Cropping Systems)

► Show Figures

Figure 1

20 pages, 10787 KiB

Open AccessEditor’s ChoiceArticle

Attempting to Estimate the Unseen—Correction for Occluded Fruit in Tree Fruit Load Estimation by Machine Vision with Deep Learning

by Anand Koirala, Kerry B. Walsh and Zhenglin Wang

Agronomy 2021, 11(2), 347; https://doi.org/10.3390/agronomy11020347 - 15 Feb 2021

Cited by 26 | Viewed by 4099

Abstract

Machine vision from ground vehicles is being used for estimation of fruit load on trees, but a correction is required for occlusion by foliage or other fruits. This requires a manually estimated factor (the reference method). It was hypothesised that canopy images could [...] Read more.

Machine vision from ground vehicles is being used for estimation of fruit load on trees, but a correction is required for occlusion by foliage or other fruits. This requires a manually estimated factor (the reference method). It was hypothesised that canopy images could hold information related to the number of occluded fruits. Several image features, such as the proportion of fruit that were partly occluded, were used in training Random forest and multi-layered perceptron (MLP) models for estimation of a correction factor per tree. In another approach, deep learning convolutional neural networks (CNNs) were directly trained against harvest count of fruit per tree. A R2 of 0.98 (n = 98 trees) was achieved for the correlation of fruit count predicted by a Random forest model and the ground truth fruit count, compared to a R² of 0.68 for the reference method. Error on prediction of whole orchard (880 trees) fruit load compared to packhouse count was 1.6% for the MLP model and 13.6% for the reference method. However, the performance of these models on data of another season was at best equivalent and generally poorer than the reference method. This result indicates that training on one season of data was insufficient for the development of a robust model. Full article

(This article belongs to the Special Issue In-Field Estimation of Fruit Quality and Quantity)

► Show Figures

Figure 1

16 pages, 2877 KiB

Open AccessEditor’s ChoiceArticle

Effect of H₂O-Based Low-Pressure Plasma (LPP) Treatment on the Germination of Bambara Groundnut Seeds

by Naeem Ahmed, Asad Masood, Kim S. Siow, M. F. Mohd Razip Wee, Rahmat Zaki Auliya and Wai Kuan Ho

Agronomy 2021, 11(2), 338; https://doi.org/10.3390/agronomy11020338 - 14 Feb 2021

Cited by 15 | Viewed by 5436

Abstract

In general, seed germination is improved by low-pressure plasma (LPP) treatment using precursors such as air, nitrogen, argon, or water (H₂O). Here, H₂O-based LPP treatment using the optimized parameters of 10 W and 10 s improves the germination of [...] Read more.

In general, seed germination is improved by low-pressure plasma (LPP) treatment using precursors such as air, nitrogen, argon, or water (H₂O). Here, H₂O-based LPP treatment using the optimized parameters of 10 W and 10 s improves the germination of Bambara groundnut seeds by 22%. LPP increases the wettability and roughness of the seed hilum while oxidizing the surface with carboxyl and amine groups. In this H₂O-based treatment of Bambara groundnut seeds, combinatory etching and chemical modification facilitated the imbibition process and increased the germination percentage. The success of this method has the potential to be scaled up to solve food security with seeds otherwise facing germination-related issues. Full article

(This article belongs to the Special Issue Applied High-Voltage Plasma Technologies in Agricultural Industry)

► Show Figures

Graphical abstract

18 pages, 2632 KiB

Open AccessEditor’s ChoiceArticle

Plant-Based Protein Hydrolysate Improves Salinity Tolerance in Hemp: Agronomical and Physiological Aspects

by Ida Di Mola, Stefano Conti, Eugenio Cozzolino, Giuseppe Melchionna, Lucia Ottaiano, Antonino Testa, Leo Sabatino, Youssef Rouphael and Mauro Mori

Agronomy 2021, 11(2), 342; https://doi.org/10.3390/agronomy11020342 - 14 Feb 2021

Cited by 49 | Viewed by 4933

Abstract

Hemp (Cannabis sativa L.) is a multipurpose plant attracting increasing interest as a source for the production of natural fibers, paper, bio-building material and food. In this research we studied the agronomical performance of Cannabis sativa cv. Eletta Campana irrigated with saline [...] Read more.

Hemp (Cannabis sativa L.) is a multipurpose plant attracting increasing interest as a source for the production of natural fibers, paper, bio-building material and food. In this research we studied the agronomical performance of Cannabis sativa cv. Eletta Campana irrigated with saline water. Under those conditions, we tested the effect of protein hydrolysate (PH) biostimulant application in overcoming and/or balancing deleterious salinity effects. The results of the diverse treatments were also investigated at the physiological level, focusing on photosynthesis by means of a chlorophyll a fluorescence technique, which give an insight into the plant primary photochemical reactions. Four salinity levels of the irrigation solution (fresh water–EC0, and NaCl solutions at EC 2.0, 4.0 or 6.0 dS m⁻¹, EC2, EC4 and EC6, respectively) were combined with 2 biostimulant treatments (untreated (control) or treated with a commercial legume-derived protein hydrolysate (LDPH)). The increasing salinity affected plant photochemistry resulting in lower plant growth and seed production, while the LDPH biostimulant showed a protective effect, which improved crop performance both in control and in salinity conditions. The LDPH treatment improved seeds yield (+38.6% on average of all treated plants respect to untreated plants), as well as residual biomass, relevant in fiber production. Full article

► Show Figures

Figure 1

29 pages, 656 KiB

Open AccessEditor’s ChoiceReview

Intercropping—A Low Input Agricultural Strategy for Food and Environmental Security

by Sagar Maitra, Akbar Hossain, Marian Brestic, Milan Skalicky, Peter Ondrisik, Harun Gitari, Koushik Brahmachari, Tanmoy Shankar, Preetha Bhadra, Jnana Bharati Palai, Jagadish Jena, Urjashi Bhattacharya, Sarath Kumar Duvvada, Sagar Lalichetti and Masina Sairam

Agronomy 2021, 11(2), 343; https://doi.org/10.3390/agronomy11020343 - 14 Feb 2021

Cited by 192 | Viewed by 32120

Abstract

Intensive agriculture is based on the use of high-energy inputs and quality planting materials with assured irrigation, but it has failed to assure agricultural sustainability because of creation of ecological imbalance and degradation of natural resources. On the other hand, intercropping systems, also [...] Read more.

Intensive agriculture is based on the use of high-energy inputs and quality planting materials with assured irrigation, but it has failed to assure agricultural sustainability because of creation of ecological imbalance and degradation of natural resources. On the other hand, intercropping systems, also known as mixed cropping or polyculture, a traditional farming practice with diversified crop cultivation, uses comparatively low inputs and improves the quality of the agro-ecosystem. Intensification of crops can be done spatially and temporally by the adoption of the intercropping system targeting future need. Intercropping ensures multiple benefits like enhancement of yield, environmental security, production sustainability and greater ecosystem services. In intercropping, two or more crop species are grown concurrently as they coexist for a significant part of the crop cycle and interact among themselves and agro-ecosystems. Legumes as component crops in the intercropping system play versatile roles like biological N fixation and soil quality improvement, additional yield output including protein yield, and creation of functional diversity. But growing two or more crops together requires additional care and management for the creation of less competition among the crop species and efficient utilization of natural resources. Research evidence showed beneficial impacts of a properly managed intercropping system in terms of resource utilization and combined yield of crops grown with low-input use. The review highlights the principles and management of an intercropping system and its benefits and usefulness as a low-input agriculture for food and environmental security. Full article

(This article belongs to the Special Issue The Adaptation of Agriculture to Climatic Change)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Editor’s Choice Articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI