Agronomy doi: 10.3390/agronomy14030616
Authors: Larissa Alves Rodrigues Lázaro da Costa Corrêa Cañizares Silvia Leticia Rivero Meza Betina Bueno Peres Silvia Naiane Jappe Newiton da Silva Timm Maurício de Oliveira Paulo Carteri Coradi
Red rice has achieved a lot of visibility due to its greater amounts of bioactive compounds compared to traditional white rice. The increased recognition of red rice by the industry is a consequence of the expansion of its study in the field of research. The red color of its grains is characteristic of the presence of proanthocyanidins, which is associated with health benefits such as reducing the risk of chronic diseases. In addition, red rice is gluten-free and hypoallergenic, which makes it suitable for celiac or gluten-intolerant patients. However, the contents of phytochemicals can vary with the influence of the adaptability of genotypes to the environment, cultivation practices, abiotic stresses, and industrial processing. In this scenario, one of the challenges is to increase the diversity of red rice products while having a minimum impact on the content of bioactive compounds, mainly flavonoids and phenolic acids. In this review, a complete overview of the importance of pigmented red rice is presented, including the effects of different genotypes, the growth environment, and industrial processing on the bioactive compounds, mainly flavonoids and phenolic acids, in red rice, and the health benefits of its products are described. Studies cited in this review article were found by searching through the Web of Science database from 2013 to 2023. After a detailed and up-to-date search, 36 studies were included in this review article.
]]>Agronomy doi: 10.3390/agronomy14030615
Authors: Silvia Antileo-Mellado Cristina Muñoz Juan Carlos Sanchez-Hernandez Milagros Ginebra Marco Sandoval
Farm and industrial residues must be adequately managed to avoid negative environmental implications. In this study, our objective was to evaluate (i) the impact of the co-production of vermicompost using grape bagasse and biochar (BC) on the yield and biochemical, chemical, and biological properties of vermicompost; (ii) the effect of BC on earthworms (Eisenia fetida Sav.). The vermicompost was co-produced over 5 months (n = 4 per treatment) using (i) grape bagasse as the substrate, (ii) earthworms (Eisenia fetida Sav.), and (iii) three BCs (eucalyptus sawdust BC, pig manure BC, and carbonaceous material from poultry litter CM) at 2% (w/w). A control without BC was included. The chemical, microbiological (activity and respiration), enzymatic properties, and enzymatic indices were characterized. After the incubation period, vermicompost yield increased with the application of the three BCs (25% on average). The number of adult earthworms was not affected by any of the BCs. Compared to treatments without BC, those with pig manure BC and eucalyptus BC resulted in maintained or significantly decreased enzymatic activity, indicating that the vermicompost was at an advanced stage of maturity. Eucalyptus BC significantly enriched the C content of the vermicompost by 4.3%, maintaining respiration rates at 18% lower than the treatment without BC. Additionally, pig manure BC generated the lowest respiration rate in the vermicompost (20% lower). We conclude that BC has a positive influence on the vermicompost process, stabilizing organic matter (especially pig manure BC) and improving the potential of vermicompost to store C (when high-C-content BCs are applied).
]]>Agronomy doi: 10.3390/agronomy14030614
Authors: Yitong Zhang Jiangtao Li Fang Lu Siqi Wang Yangjie Ren Shiyang Guo Ben Wang Wei Gao
The widespread use of non-renewable phosphate fertilizers in agriculture poses a significant pollution threat to soil, necessitating the exploration of sustainable alternatives for phosphate fertility. Releasing phytate phosphorus through microbial phytases presents an eco-friendly solution for sustainable phosphate fertility in agriculture. This study directly inoculated dual-domain β-propeller alkaline phytase (phyHT) derived from Bacillus sp. HJB17 into the soil. The study analyzed the impact of inoculated phyHT on the physicochemical properties of the soil, assessed the variations in enzyme activity of phyHT within the soil, and examined the effects of the treated soil on wheat growth. Additionally, the study explored the enhancement of the available phosphorus in the soil through the inoculation of phyHT in both crop residues and organic fertilizer. PhyHT exhibited the highest catalytic activity at 37 °C and pH 8.0. After soil adsorption, phyHT maintained stable enzymatic activity. PhyHT markedly boosted the available phosphorus in the soil while reducing the soil phytate content by about 20%, increasing the phosphorus levels and enhancing soil fertility. PhyHT effectively degraded phytates in an organic fertilizer and crop residues, increasing the available phosphorus. PhyHT supplementation enhanced growth, biomass, and phosphorus content in both the shoot and root weights of Triticum aestivum. This study establishes phyHT as a viable and eco-friendly method to enhance phosphorus fertility in soil. The direct application of microbial phytases can serve as a sustainable source of phosphate fertility in soil.
]]>Agronomy doi: 10.3390/agronomy14030613
Authors: Francisco Altimiras Leonardo Pavéz Alireza Pourreza Osvaldo Yañez Lisdelys González-Rodríguez José García Claudio Galaz Andrés Leiva-Araos Héctor Allende-Cid
In agricultural production, it is fundamental to characterize the phenological stage of plants to ensure a good evaluation of the development, growth and health of crops. Phenological characterization allows for the early detection of nutritional deficiencies in plants that diminish the growth and productive yield and drastically affect the quality of their fruits. Currently, the phenological estimation of development in grapevine (Vitis vinifera) is carried out using four different schemes: Baillod and Baggiolini, Extended BBCH, Eichhorn and Lorenz, and Modified E-L. Phenological estimation requires the exhaustive evaluation of crops, which makes it intensive in terms of labor, personnel, and the time required for its application. In this work, we propose a new phenological classification based on transcriptional measures of certain genes to accurately estimate the stage of development of grapevine. There are several genomic information databases for Vitis vinifera, and the function of thousands of their genes has been widely characterized. The application of advanced molecular biology, including the massive parallel sequencing of RNA (RNA-seq), and the handling of large volumes of data provide state-of-the-art tools for the determination of phenological stages, on a global scale, of the molecular functions and processes of plants. With this aim, we applied a bioinformatic pipeline for the high-throughput quantification of RNA-seq datasets and further analysis of gene ontology terms. We identified differentially expressed genes in several datasets, and then, we associated them with the corresponding phenological stage of development. Differentially expressed genes were classified using count-based expression analysis and clustering and annotated using gene ontology data. This work contributes to the use of transcriptome data and gene expression analysis for the classification of development in plants, with a wide range of industrial applications in agriculture.
]]>Agronomy doi: 10.3390/agronomy14030612
Authors: Yayi Wang Rong Zhang Songling Li Xinnian Guo Quanhui Li Xiaoli Hui Zhaohui Wang Huixia Wang
Unreasonable fertilization often fails to match crop yield and nutrient requirements, leading to low crop yield, the waste of mineral resources, and increased costs for farmers. A survey of the potato yield and fertilization of farmers was conducted in Haidong City of Qinghai Province for three consecutive years (2017–2019) torecommend reasonable fertilizer application. The results showed that the required amount of NPK fertilizer per ton of potato was 4.85 kg N, 1.26 kg P2O5, and 6.98 kg K2O, respectively. The potato yields ranged from 7500 to 66,429 kg ha−1, with an average of 26,069 kg ha−1. The average N, P, and Kfertilizers (in the form of N, P2O5, and K2O, respectively) applied by the farmers were 213 kg N ha−1, 202 kg P2O5ha−1, and 43 kg K2O ha−1. More than 60% of the farmers appliedtoo much Nand Pfertilizers and too little Kfertilizer. Therefore, the farmers with lowyieldsshould reduce the application of Nand P fertilizers by a range of 41–220 kg ha−1 and 24–265 kg ha−1. Allthe farmers should increase Kfertilizer use by 7–273 kg ha−1. Reasonable fertilization could effectively conserve resources, improve economic efficiency, and reduce environmental impact.
]]>Agronomy doi: 10.3390/agronomy14030611
Authors: Bakry A. Bakry Mervat Sh. Sadak Nagla M. Al Ashkar Omar M. Ibrahim Mohammad K. Okla Amira M. El-Tahan
Drought stress is an important challenge to global food security and agricultural output, and dramatic and rapid climate change has made the problem worse, causing unexpected impacts on the growth, development, and yield of different plants. Understanding the biochemical, ecological, and physiological reactions to these pressures is essential for improved management. Carbon materials’ impacts on plants subjected to different stresses are still poorly studied. Thus, this study was carried out investigate the feasibility of applying carbon nanotubes (CNTs) (0, 20, and 40 mg/L) as a foliar treatment for mitigating the effect of water stress (100%, 75%, and 50% irrigation water, IW) on peanut plants growing in sandy soil through assessments of growth and productivity and some physiological and biochemical measurements. Exposure of peanuts to decreased irrigation water led to significant decreases in growth, yield, photosynthetic pigments, indole acetic acid (IAA), and some nutritional components in peanut seeds, but increased levels of osmolytes such as total soluble carbohydrates (TSS) and proline, in addition to free amino acids and phenolics. However, foliar spraying with CNTs could ameliorate the impacts of decreased irrigation water on growth and production via enhancing the studied physiological parameters, such as photosynthetic pigments, IAA, osmolytes, and phenolics. Furthermore, the application of carbon nanotubes improved the nutrient contents, as expressed by the oil yield, protein yield, total carbohydrates, antioxidant activities (DPPH), B-carotene, lycopene, and flavonoids in peanut seeds, either under normal or water stress conditions. The higher level of CNTs (40 mg/L) was more effective than the lower one (20 mg/L) at increasing the above-mentioned parameters. In conclusion, foliar treatment with carbon nanotubes has the ability to enhance peanut drought tolerance and increase its growth and productivity under sandy soil conditions.
]]>Agronomy doi: 10.3390/agronomy14030610
Authors: Saeid Hazrati Giuseppe Pignata Manuela Casale Seyyed Jaber Hosseini Silvana Nicola
The optimal fertilizer concentration for Mentha plants is contingent on the growing systems and harvest time, serving as operational solutions to control and enhance quality and yield. This study aimed to determine the effects of three macronutrients concentration in hydroponic nutrient solution (HNS) during three harvest times on the growth, quality, yield, and shelf life of three mint species (M. spicata L. var. viridis (MV); M. piperita L. (MP); M. spicata L. var. rubra (MR)) grown in a New Growing System (NGS®). Total dry matter (DM), nitrate (NO3−), phosphate (PO43−), and calcium carbonate (CaCO3) concentrations were increased with the addition of higher levels of nutrient fertilization in three species. When the ion concentration of the HNS was increased, total fresh yield decreased. The highest total bacterial count (TBC) was obtained in MR species in the three harvests in all the levels of HNS. The lowest browning potential (BP) and soluble o-quinone (So-Q) levels were observed at second harvest in the MR species with the application of one of the two HNS high in nitrogen (N). In conclusion, the combination of optimal HNS ion concentration and appropriate species is considered essential to obtain suitable yield, quality, and ensure shelf life of mint.
]]>Agronomy doi: 10.3390/agronomy14030609
Authors: Xinpei Wei Benkang Xie Chu Wan Renfeng Song Wanru Zhong Shuquan Xin Kai Song
Soil microorganisms play a crucial role in maintaining the structure and function of soil ecosystems. This study aims to explore the effects of microbial fertilizers on improving soil physicochemical properties and promoting plant growth. The results show that the application of microbial fertilizers significantly increases the richness of soil microorganisms, maintains soil microecological balance, and effectively improves the soil environment. Through various secondary metabolites, proteins, and mucilage secreted by the developing plant root system, microbial fertilizers recruit specific fungal microorganisms. These microorganisms, by binding soil particles with their extracellular polysaccharides and entwining them, fix the soil, enhance the stability of soil aggregates, and ameliorate soil compaction. Moreover, after the application of microbial fertilizers, the enriched soil microbial community not only promotes the plant’s absorption and utilization of key elements such as nitrogen (N), phosphorus (P), and potassium (K), thereby increasing fruit yield and quality, but also competes with pathogens and induces systemic resistance in plants, effectively warding off pathogenic invasions. This study highlights the potential and importance of microbial fertilizers in promoting sustainable agricultural development, offering new strategies and perspectives for future agricultural production.
]]>Agronomy doi: 10.3390/agronomy14030608
Authors: Huifang Wang Bangbang Yang Xinyu Zhao Hailong Chen Fei Liu Yating Ru Xirui Wei Xiaofeng Fu Weiwei Guo Ximei Li Nataliia Golub Yumei Zhang
Root architectural traits at the seedling stage have been demonstrated to be crucial for the efficient uptake of nutrients and drought tolerance in wheat. To dissect the genetic basis of these traits from the D genome, 182 recombinant inbred lines (RILs) derived from the common wheat TAA10 crossed with resynthesized allohexaploid wheat XX329 possessed similar AABB genomes were used for QTL mapping of five root traits in hydroponic-cultured seedlings, including lateral root number (LRN), seminal root number (SRN), root hair length (RHL), root diameter (RD), and total root volume (TRV). A total of seven QTLs were identified for the five root traits, with six possible novel QTLs for LRN, RHL, RD and TRV, accounting for 4.98–12.17% of phenotypic variation. One QTL (QLrn.qau-5D.2), controlling lateral root number, was fine mapped an approximate 5.0-Mb interval harboring 80 annotated genes, including five auxin-related genes. We further validated that QLrn.qau-5D.2 in NILTAA10 significantly enhanced yield-related traits, such as plant height, spike length, spike compactness, tiller number per plant and grain yield per plant, as comparison with NILXX329. Collectively, these results provide vital insights for fine-mapping QTLs associated with LRN, SRN, RHL, RD and TRV and facilitate the root morphologic designs for enhancing yield performance.
]]>Agronomy doi: 10.3390/agronomy14030607
Authors: Yalin Gao Jinghai Wang Yanlin Ma Minhua Yin Qiong Jia Rongrong Tian Yanxia Kang Guangping Qi Chen Wang Yuanbo Jiang Haiyan Li
Wolfberry (Lycium barbarum L.) production in arid and semi-arid areas is drastically affected by the low utilization rate of soil and water resources and the irrational application of water and nitrogen fertilizers. Thus, this study explored a high-yielding, high-quality, and efficient irrigation and nitrogen regulation model to promote the production efficiency of wolfberry and rational utilization of water and land resources in arid and semi-arid areas. We compared and analyzed the effects of different soil water treatments (the upper and lower limits of soil water were estimated as the percentage of soil water content to field water capacity (θf), with the following irrigation regimen: adequate irrigation (W0, 75–85% θf), mild water deficit (W1, 65–75% θf), moderate water deficit (W2, 55–65% θf), and severe water deficit (W3, 45–55% θf)) and nitrogen levels (no nitrogen (N0, 0 kg·ha−1), low nitrogen (N1, 150 kg·ha−1), moderate nitrogen (N2, 300 kg·ha−1), and high nitrogen (N3, 450 kg·ha−1)) on the growth, physiology, and production of wolfberry. The results showed that water regulation, nitrogen application level, and their interaction significantly affected plant height and stem diameter growth amount (p < 0.05). Additionally, the relative chlorophyll content of wolfberry leaves first increased and then decreased with increasing nitrogen levels and water deficit. The average net photosynthetic rate (Pn), stomatal conductance (gs), intercellular carbon dioxide concentration, and transpiration rate (Tr) reached the highest values in plants exposed to W0N2 (19.86 μmmol·m−2·s−1), W1N1 (182.65 mmol·m−2·s−1), W2N2 (218.86 μmol·mol−1), and W0N2 (6.44 mmol·m−2·s−1) treatments, respectively. Pn, gs, and Tr were highly correlated with photosynthetically active radiation and water vapor pressure difference (goodness-of-fit: 0.366–0.828). Furthermore, water regulation and nitrogen levels exhibited significant effects on the yield and water- (WUE), and nitrogen-use efficiency (NUE) (p < 0.01), and their interactions exhibited significant effects on the yield, WUE, and nitrogen partial productivity of wolfberry plants (p < 0.05). Moreover, the contents of total sugar, polysaccharides, fats, amino acids, and proteins were the highest in W1N2, W1N2, W1N2, W2N3, and W0N2 treatments, respectively, which were increased by 3.32–16.93%, 7.49–54.72%, 6.5–45.89%, 11.12–86.16%, and 7.15–71.67%, respectively. Under different water regulations (except for the W3 condition) and nitrogen level treatments, the net income and input–output ratio of wolfberry were in the order W1 > W0 > W2 > W3 and N2 > N3 > N1 > N0. The TOPSIS method also revealed that the yield, quality, WUE, NUE, and economic benefits of wolfberry improved under the W1N2 treatment, suggesting that WIN2 might be the most suitable irrigation and nitrogen regulation model for wolfberry production in regions with scarce land and water resources such as the Gansu Province and areas with similar climate.
]]>Agronomy doi: 10.3390/agronomy14030606
Authors: József Prokisch Greta Törős Duyen H. H. Nguyen Chaima Neji Aya Ferroudj Daniella Sári Arjun Muthu Eric C. Brevik Hassan El-Ramady
The relationship between agriculture and food is very close. It is impossible to produce adequate crops for global food security without proper farm management. Farming practices represent direct and indirect controlling factors in terms of global food security. Farming management practices influence agro-food production from seed germination through to the post-harvest treatments. Nano-farming utilizes nanotechnologies for agricultural food production. This review covers four key components of nano-farming: nano-mushroom production, protein-based nanoparticles, nano-nutrients, and nanofibers. This provides a comprehensive overview of the potential applications of nanotechnology in agriculture. The role of these components will be discussed in relation to the challenges faced and solutions required to achieve sustainable agricultural production. Edible mushrooms are important to food security because they are a nutritious food source and can produce nanoparticles that can be used in the production of other food sources. Protein-based nanoparticles have considerable potential in the delivery of bioactives as carriers and other applications. Nano-nutrients (mainly nano-selenium, nano-tellurium and carbon nanodots) have crucial impacts on the nutrient status of plant-based foods. Carbon nanodots and other carbon-based nanomaterials have the potential to influence agricultural crops positively. There are promising applications of nanofibers in food packaging, safety and processing. However, further research is needed to understand the impacts and potential risks of nanomaterials in the food production system.
]]>Agronomy doi: 10.3390/agronomy14030605
Authors: Antonios Chrysargyris Panayiota Xylia Nikolaos Tzortzakis
The intensive cultivation of olive trees and grapevines in the Mediterranean region not only results in large yields but also generate wastes, with high restrictions on their impact on people’s well-being and the environment. The current study sought to investigate the potential use of olive-mill waste (OW), grape-mill waste (GW) and their mixtures (OW + GW) at different levels (0%, 5%, 10% and 20% v/v) for partial peat substitution in the production of carnation (Dianthus caryophyllus L.) plants. The presence of OW, GW and OW + GW wastes raised the pH, the electrical conductivity, the content of organic matter and mineral content in substrate mixtures, while they decreased the total porosity and the available free air. The use of OW had more negative impacts than GW, while the OW + GW mixture alleviated, to some extent, the negative OW impacts. The use of high levels of residues decreased plant growth, chlorophyll content and mineral accumulation in plant tissue due to inappropriate growing media properties. The increased OW presence caused oxidative stress to the plants, as verified by the increased malondialdehyde and hydrogen peroxide content. This resulted in an upsurge in the total phenolics. However, GW presence did not impact any oxidative stress. It can be suggested that 10% OW, 10% GW or 20% OW + GW can be used in growing media, as they resulted in suitable plant growth. To ensure sufficient yields, nevertheless, the growing media’s characteristics also need to be enhanced.
]]>Agronomy doi: 10.3390/agronomy14030604
Authors: Wei Yang Guo-Feng Wan Jia-Qi Zhou Gen-Cai Song Jing Zhao Feng-Lin Huang Shuan Meng
Nitrogen and brassinosteroids (BRs) play a vital role in modulating the growth, development, and yield of rice. However, the influences of BRs on nitrogen assimilation and metabolism in rice are not fully understood. In this study, we analyzed the impact of BRs on nitrogen utilization in rice using the indica variety ‘Zhongjiazao 17’ and the japonica variety ‘Nipponbare’ in hydroponic conditions. The results showed that BR treatment could efficiently elevate nitrate and ammonium nitrogen accumulation in both shoots and roots. Furthermore, some genes involved in the uptake of nitrate and ammonium in roots were stimulated by BRs, though we noted subtle variances between the two rice cultivars. Moreover, BRs augmented the activity of nitrate reductase (NR) and glutamine synthetase (GS) in roots, along with NR in shoots. Interestingly, BRs also spiked the total free amino acid content in both the shoots and roots. Gene expression analysis uncovered a robust induction by BRs of NR genes and GS-related genes in the roots of both ‘Nipponbare’ and ‘Zhongjiazao 17’. Collectively, our data suggest that BRs significantly enhance the accumulation of both nitrate and ammonium in rice and trigger a series of reactions related to nitrogen utilization.
]]>Agronomy doi: 10.3390/agronomy14030603
Authors: Yubo Li Qin Zhu Yang Zhang Shuang Liu Xiaoting Wang Enheng Wang
Winter cover crops have been shown to promote the accumulation of microbial biomass carbon and nitrogen, enhance nutrient cycling, reduce erosion, improve ecosystem stability, etc. In the black soil area of Northeast China, Triticum aestivum L., Medicago sativa L., Vicia villosa Roth., Triticum aestivum L. and Medicago sativa L. mixed planting, Triticum aestivum L. and Vicia villosa Roth. mixed planting, and winter fallow fields (CK) were selected to investigate the effects of winter cover crops on soil total carbon and nitrogen and microbial biomass carbon and nitrogen. The results showed that (1) after seasonal freeze-thaw, the rate of change in SOC (−2.49~6.50%), TN (−1.54~5.44%), and C/N (−1.18~1.16%) was less than that in SMBC (−80.91~−58.33%), SMBN (−65.03~332.22%), and SMBC/SMBN (−45.52~−90.03%); (2) winter cover crops not only alleviated the negative effects of seasonal freeze-thaw, which reduces SMBC and qMBC, but also increased SMBN and qMBN; (3) there was an extremely significant (p < 0.01) positive correlation between SOC and TN, a significant (p < 0.05) negative correlation between SMBC and SMBN, and there was no significant correlation between SOC and SMBC or between TN and SMBN; (4) alkali-hydrolysable nitrogen had the greatest impact on SOC and TN, while the soil’s saturation degree had the greatest impact on SMBC and SMBN; and (5) the Triticum aestivum L. monoculture was the most effective in conserving soil microbial carbon and nitrogen. In conclusion, winter cover crops can mitigate the reduction in soil microbial biomass carbon caused by seasonal freeze-thaw and also increase the soil microbial nitrogen content in the black soil region of Northeast China, of which Triticum aestivum L. monoculture showed the best performance.
]]>Agronomy doi: 10.3390/agronomy14030601
Authors: Jingying Hei Yue Li Qiong Wang Shu Wang Xiahong He
Panax notoginseng (Sanqi) is a precious traditional Chinese medicine that is commonly cultivated using conventional management methods in agricultural systems in Yunnan, China, where it faces the challenge of continuous cropping obstacles (CCOs). However, the existence of Sanqi CCOs in Sanqi–pine agroforestry systems remains unclear. Here, we applied three types of exogenous organic acids (phthalic acid, palmitic acid, and phthalic + palmitic mixed organic acids) mainly derived from the root exudates of Sanqi to simulate the CCOs; then, we compared the effects on plant growth, soil physicochemical properties, soil microbes, and soil metabolites. We found that organic acid concentrations of >250 mg/kg reduced the fresh weight of Sanqi and the levels of total nitrogen, ammonium nitrogen, soil water content, total phosphorus, and pH value; these concentrations also increased the soil bacterial and fungal α-diversity. The type of organic acid, as opposed to the concentration and duration of treatment, had a vital impact on the structure of the bacterial and fungal community in Sanqi soils. Moreover, the organic acid concentrations of >250 mg/kg also decreased the complexity and stability of the bacterial and fungal network. In addition, the metabolic pathways in the soils under different organic acids included 17 differential metabolites (DMs), which were involved in steroid hormone biosynthesis. The structural equation models (SEMs) revealed that plant growth, soil edaphic factors, and soil metabolites had direct or indirect influences on soil microbial communities under different organic acid conditions. Our results suggest that any phthalic or palmitic acid concentrations at concentrations >250 mg/kg are detrimental to multiple aspects of Sanqi cultivation, confirming the presence of Sanqi CCOs in Sanqi–pine agroforestry systems.
]]>Agronomy doi: 10.3390/agronomy14030602
Authors: Dongxue Zhao Yingli Cao Jinpeng Li Qiang Cao Jinxuan Li Fuxu Guo Shuai Feng Tongyu Xu
Leaf blast is recognized as one of the most devastating diseases affecting rice production in the world, seriously threatening rice yield. Therefore, early detection of leaf blast is extremely important to limit the spread and propagation of the disease. In this study, a leaf blast-specific spectral vegetation index RBVI = 9.78R816−R724 − 2.08(ρ736/R724) was designed to qualitatively detect the level of leaf blast disease in the canopy of a field and to improve the accuracy of early detection of leaf blast by remote sensing by unmanned aerial vehicle. Stacking integrated learning, AdaBoost, and SVM were used to compare and analyze the performance of the RBVI and traditional vegetation index for early detection of leaf blast. The results showed that the stacking model constructed based on the RBVI spectral index had the highest detection accuracy (OA: 95.9%, Kappa: 93.8%). Compared to stacking, the detection accuracy of the SVM and AdaBoost models constructed based on the RBVI is slightly degraded. Compared with conventional SVIs, the RBVI had higher accuracy in its ability to qualitatively detect leaf blast in the field. The leaf blast-specific spectral index RBVI proposed in this study can more effectively improve the accuracy of UAV remote sensing for early detection of rice leaf blast in the field and make up for the shortcomings of UAV hyperspectral detection, which is susceptible to interference by environmental factors. The results of this study can provide a simple and effective method for field management and timely control of the disease.
]]>Agronomy doi: 10.3390/agronomy14030600
Authors: Shanshan Jiang Hui Li Hainuo Wang Xiaoxia Liu Kongming Wu
Wheat aphids are major pests of wheat and a significant threat to global food security. Eupeodes corollae Fabricius is one of the dominant species of wheat field hoverflies, but its ability and role in wheat aphid control lack systematic research. This study on the predatory function responses of E. corollae to Rhopalosiphum padi Linnaeus, Schizaphis graminum Rondani, and Sitobion miscanthi, Takahashi showed that the maximum daily predation (1/Th) of 2nd instar E. corollae larvae was 166.67, 125.00, and 142.86, and that of 3rd instar larvae was 333.33, 250.00, and 250.00, respectively. The cage simulation test indicated that the wheat aphid population decline rate was 100% at the 60th hour of inoculation of 3rd instar E. corollae larvae at a 1:100 ratio. Eupeodes corollae exhibited a predatory relationship with all three wheat aphid species in the wheat fields of Hebei Province, China, and the corrected predation detection rates of E. corollae larvae against R. padi, S. graminum, and S. miscanthi were 12.36%, 1.08%, and 28.77% in 2022, and 6.74%, 0.82%, and 37.56% in 2023, respectively. The results of this study clarify the predatory ability of E. corollae on wheat aphids and the predatory relationship between them and provide technical support for the management of wheat aphids using the bio-control ecological service function of E. corollae.
]]>Agronomy doi: 10.3390/agronomy14030599
Authors: Tianbao Huang Zhenhua Wang Li Guo Haiqiang Li Mingdong Tan Jie Zou Rui Zong Yam Prasad Dhital
The evaluation of soil particle composition and salt dynamics is essential for promoting the sustainable development of oasis agriculture in arid regions under long-term mulched drip irrigation (MDI). In this study, we employed the space-for-time substitution method to investigate the long-term effects of MDI on soil particle composition and salinity. Additionally, seven fields, with MDI durations ranging from 0 to 16 years, were selected to represent the primary successional sequence though time in Northwest China. Soil samples were collected from three soil depths (0–30 cm, 30–60 cm, and 60–100 cm) and then analyzed in the laboratory for soil particle composition and salt content. Our findings demonstrated that influenced by the depth of mechanical cultivation and the maximum wetting front depth, the long-term application of MDI significantly altered both the structure of soil layers and the composition of soil particles after 8 years. Soil sand content and soil salinity gradually decreased, whereas the content of soil silt and clay increased with increasing MDI duration throughout 0–100 cm soil depth. Furthermore, the rates of soil desalination stabilized after 10 years of MDI application, with desalination levels exceeding 90% in the 0–100 cm soil layer. Additionally, the soil mass fractal dimension (Dm) exhibited an upward trend across 0–100 cm soil depth. The changes in soil particle composition indirectly influenced the variations in Dm and salt content. Our study demonstrated that long-term application of MDI effectively mitigated soil salinity, changed soil structure, and ultimately enhanced soil quality and cotton yield.
]]>Agronomy doi: 10.3390/agronomy14030596
Authors: Roberto Barbetti Irene Criscuoli Giuseppe Valboa Nadia Vignozzi Sergio Pellegrini Maria Costanza Andrenelli Giovanni L’Abate Maria Fantappiè Alessandro Orlandini Andrea Lachi Lorenzo Gardin Lorenzo D’Avino
A WebGis tool called GoProsit has been developed to support winegrowers in planning a new sustainable vineyard and in the identification of high-quality terroir in Tuscany, Central Italy, by providing various information on soils, climate, hydrological risks, and fertilization. GoProsit, hosted by the web platform GEAPP, is a free, user-friendly, and interactive Geographic Decision Support System (GDSS). Soil data behind the WebGis tool has a 1 ha resolution, achieved by processing the legacy vector-type soil database of the Tuscany Region with the DSMART (Disaggregation and Harmonization of Soil Map Units Through Resampled Classification Trees as supervised classification) algorithm, which disaggregated the map to 297,023 vineyard grid cells. Each grid cell holds climatic and pedologic information, along with physical and chemical features for each horizon of the most probable soil. GoProsit also provides soil maps in image format obtained by georeferencing about 50 historical soil maps (1969–2012). Finally, GoProsit runs and returns the outputs of six models: (a) carbon footprint, (b) potential erosion and maximum vine row length compatible with tolerable erosion, (c) potential water stress, (d) risk of runoff/waterlogging, (e) identification of suitable rootstocks, and (f) nutritional needs before planting. Statistics of the main model results for the investigated area are reported. This promising tool will soon be usable for the whole Italian territory; however, its potential makes it suitable for use in any wine-growing district.
]]>Agronomy doi: 10.3390/agronomy14030597
Authors: Lilia Mexicano Tarsicio Medina Adriana Mexicano Jesús-Carlos Carmona
Bacterial speck disease in tomato crops is caused by Pseudomonas syringae pv. tomato. Chemical control is mainly used for the control of phytopathogens, which carries a risk for both human health and the environment, making it necessary to search for environmentally friendly alternatives, such as the use of electrolyzed water. In the present study, preventive treatments were applied to tomato plants of the saladette variety. The treatments employed were electrolyzed oxidizing water (EOW), electrolyzed reduced water (ERW), a commercial bactericide (Kasumin), and untreated plants as the base control. During the vegetative stage, the disease severity, stem diameter, number of leaves, and number of clusters were determined. In addition, the soluble solids (°Brix), titratable acidity (TA), pH, color, polar and equatorial diameter, weight, and weight loss of the harvested fruit were determined. According to the results, the lowest severity was obtained in the plants treated with oxidizing water, achieving results similar to those achieved with the commercial bactericide Kasumin. It can be concluded that oxidizing water can be applied to tomato crops since its effect is similar to that of Kasumin, but without affecting the growth and development of the crop. Moreover, it is environmentally friendly.
]]>Agronomy doi: 10.3390/agronomy14030598
Authors: Xueqi Su Xiaomeng Guo Qian Chen Zheng Sun Xianchao Shang Yun Gao Tao Yu Li Zhang Long Yang Xin Hou
Unreasonable cultivation methods and management measures have led to widespread obstacles in tobacco continuous cropping in planting areas, resulting in reduced tobacco yield and soil degradation. Therefore, intercropping tobacco with other crops is an effective strategy to improve continuous cropping barriers. In this study, flue-cured tobacco NC102 and conventional planting varieties of Salvia miltiorrhiza were used as materials, and four treatments of flue-cured tobacco monoculture (CK), flue-cured tobacco, and Salvia miltiorrhiza at a ratio of 1:1 (TS11), 2:2 (TS22), and 2:3 (TS23), respectively, were set up to study their effects on soil microorganisms, physical and chemical properties, and yield and quality of flue-cured tobacco. The results showed that intercropping Salvia miltiorrhiza increased the number of soil bacteria and actinomycetes, decreased the number of fungi, and increased the activity of urease and sucrase. The content of available nitrogen and available phosphorus in intercropping Salvia miltiorrhiza soil was significantly higher than that of the flue-cured tobacco monoculture, while the content of available potassium was lower than that of the flue-cured tobacco monoculture. The soil environment was more conducive to the growth of flue-cured tobacco. Compared with the flue-cured tobacco monoculture, the proportion of superior tobacco in intercropping Salvia miltiorrhiza increased by 2.2–3.4%, and the ratio of potassium to chlorine in leaves of different parts of flue-cured tobacco increased by 12.3–75.0%. The content of total sugar and soluble sugar in middle and upper leaves of intercropping flue-cured tobacco was higher than that of the flue-cured tobacco monoculture, which improved the quality of flue-cured tobacco. From the analysis of the chemical composition of tobacco leaves, TS11 (flue-cured tobacco and Salvia miltiorrhiza intercropping row ratio of 1:1) had the best treatment effect, potassium content, total sugar, reducing sugar content, and potassium chloride ratio of flue-cured tobacco were the highest, the chlorine content was the lowest, and the quality was better than other treatments. From the analysis of total output value, the total output value of TS22 (flue-cured tobacco and Salvia miltiorrhiza intercropping row ratio of 2:2) was higher than that of other intercropping treatments. In 2018 and 2019, the total output value increased by 21.3% and 22.4%, respectively, compared with the flue-cured tobacco monoculture. The intercropping advantage was obvious, and the treatment effect was the best.
]]>Agronomy doi: 10.3390/agronomy14030595
Authors: Zhijuan Qi Sheng Guan Zhongxue Zhang Sicheng Du Sirui Li Dan Xu
Methane (CH4), which is an important component of the greenhouse gases from paddy ecosystems, is a major contributor to climate change. CH4 emissions from paddy ecosystems are closely related to the rice root system; however, how the rice root system affects CH4 emissions remains unclear. We conducted a field experiment in 2023 at the Heping Irrigation District Rice Irrigation Experiment Station in Qing’an County, Heilongjiang Province. The field experiment used five local rice varieties with similar fertility periods to observe rice root morphology and physiology indexes, CH4 emission fluxes, and cumulative CH4 emissions. A structural equation model (SEM) was established to investigate the effects of root characteristics on the CH4 emissions from rice and understand the potential mechanisms of these effects. The results showed that the seasonal patterns of CH4 emission fluxes were similar in different rice varieties, and that, during the tillering to heading–flowering stages, the cumulative CH4 emissions accounted for 89.8–92.6% of the total cumulative CH4 emissions of rice. Significant negative correlations were observed between CH4 emission fluxes and root volume, root dry weight, root oxidation activity (ROA), and root radial oxygen loss (ROL) (r = −0.839, −0.885, −0.401 and −0.934, p < 0.05), while there were significant positive correlations between root diameter; malic acid, citric acid, and succinic acid contents; and CH4 emission fluxes (r = 0.407, 0.753, 0.797, and 0.685, p < 0.05). The SEM showed that CH4 emission fluxes were directly influenced by ROL and organic acid contents, while the other root indicators had indirect effects by modulating ROL and organic acid contents. ROL and root volume had the largest total effect, indicating that ROL and root volume were the most significant root physiological and morphological indicators affecting CH4 emission fluxes. This study provides theoretical support and reference data for achieving sustainable agricultural development in the black soil region of Northeast China.
]]>Agronomy doi: 10.3390/agronomy14030594
Authors: Panpan Liu Dong Wang Yue Li Ji Liu Yongxing Cui Guopeng Liang Chaoqun Wang Chao Wang Daryl L. Moorhead Ji Chen
Although crop conversion from annual to perennial crops has been considered as one path towards climate-smart and resource-efficient agriculture, the effects of this conversion on soil multifunctionality and biomass yields remain unclear. The objective of the study is to enhance soil multifunctionality while exerting a marginal influence on farmer income. Here, we investigated the effects of annual winter wheat (Triticum aestivum L.) and two perennial crops (a grass (Lolium perenne L.), a legume (Medicago sativa L.), and their mixture) on soil multifunctionality and biomass yield on the Yellow River floodplain. Soil multifunctionality was assessed by the capacity of water regulation and the multifunctionality of carbon (C), nitrogen (N), and phosphorus (P) cycles. C cycle multifunctionality index is the average of β-xylosidase, β-cellobiosidase, and β-1, 4-glucosidase. N cycle multifunctionality index is the average of L-leucine aminopeptidase and β-1, 4-N-acetyl-glucosaminidase, and acid phosphatase represented (and dominated) P cycle functions. The results showed that perennial crops enhanced soil multifunctionality by 207% for L. perenne, 311% for M. sativa, and 438% for L. perenne + M. sativa, compared with annual winter wheat (T. aestivum). The effect of perennial crops on soil multifunctionality increased with infiltration rate, dissolved organic C, microbial biomass C, and extracellular enzymatic activities for both C and N acquisition. However, we observed that perennial crops had a lower biomass yield than annual crop. Therefore, the transition of agricultural landscapes to perennials needs to take into account the balance between environmental protection and food security, as well as environmental heterogeneity, to promote sustainable agricultural development.
]]>Agronomy doi: 10.3390/agronomy14030593
Authors: Juanjuan Li Changnan Yang Xuezhi Zhang Shengbiao Wu Hailong Chi Xinjiang Zhang Changzhou Wei
The cultivation of drip-irrigated rice has resulted in lower yields. However, the decrease in rice yield under drip irrigation and its relationship with the existing water and N regime have not been fully explained. Research and development of optimized water and N-management techniques are crucial for increasing rice yield under drip irrigation. In this study, two irrigation treatments were set: conventional drip irrigation (DIO) and drip irrigation with water stress (DIS). Each irrigation treatment contained four N rates: urea N 240 kg ha−1 (LN), urea N 300 kg ha−1 (MN), urea N 360 kg ha−1 (HN), and ammonium sulfate N 300 kg ha−1 (AN). The soil’s ammonium and nitrate contents were measured on the 2nd and 28th days after N application at panicle initiation stage. At anthesis, the aboveground and root biomass of rice were measured. In heading and maturity stage the N content of aboveground was measured and the yield, yield components, and NPFP were assessed at maturity stage. The results showed the following: (1) On the second day after N application, the contents of soil NO3−-N and NH4+-N in the 0–10 cm soil layer were highest for both the DIO and DIS. On the 28th day after N application, the soil NO3−-N content was highest at the 20–40 cm depth, while the soil NH4+-N content was still highest at the 0–10 cm depth. (2) The aboveground and root biomass in DIO treatment were significantly higher than in DIS. Furthermore, the root biomass at the 0–10 cm depth was significantly greater than at the 10–50 cm depth for both the DIO and DIS treatments. In the DIO treatment, the root biomass at the 10–50 cm depth was significantly higher with the HN and AN treatments compared to MN. However, in the DIS treatment, the root biomass at the 10–50 cm depth did not show significant differences between the MN, HN, and AN. (3) N accumulation in rice was significantly higher for the DIO treatment compared to the DIS treatment. Under the same irrigation treatment, the N accumulation in rice was highest in the AN and lowest in the LN. The PrNTA and PrNTC in DIS were significantly higher than in DIO, while the PoNAA and PoNAC were significantly lower in DIS. (4) The number of panicles, spikelets per panicle, seed-setting rate, 1000-grain weight, and grain yield were significantly lower in DIS. Under the DIS, these parameters were not significantly different among the MN, HN, and AN. In the DIO, the seed-setting rate, 1000-grain weight, and yield were not significantly different between the HN and AN, but were significantly higher than in the MN and LN. (5) NPFP was significantly higher in the DIO compared to the DIS. Among the different N rates, NPFP was highest with the AN treatment and lowest with the LN. In summary, under drip irrigation, there was a mismatch between soil mineral N and the distribution of rice roots, leading to reduced N accumulation and utilization in rice, ultimately impacting yield formation. Increasing N application and soil ammonium nutrition can improve rice yield under drip irrigation. However, optimizing N fertilizer management may not increase rice yield further when irrigation is further limited.
]]>Agronomy doi: 10.3390/agronomy14030592
Authors: Cristina Muñoz Milagros Ginebra Erick Zagal
The use of organic waste in agricultural soil can enhance crop yields, improve waste management, and boost soil carbon (C) sequestration. However, more field data are required to fully understand the impacts of pyrolyzed and unpyrolyzed animal manures. The objectives of this study were (i) to analyze the impact of two pyrolyzed and unpyrolyzed manures on soil properties, soil C storage, and clover productivity and (ii) to examine the biochar’s movement through the soil profile. Poultry litter (PL), dairy manure (DM), poultry litter biochar (PLBC), and dairy manure biochar (DBC) were applied at rates of 8 t ha−1 in a field experiment with red clover (Trifolium pratense L. var. Quiñequeli) in an Andisol. We monitored changes in soil chemical properties, foliar properties, and crop yield after three clover cuttings. To examine the movement of biochars through the soil profile, we set up a lab experiment where field conditions were simulated. PLBC, DBC, and PL increased soil pH by 0.5 (6.44), 0.28 (6.22), and 0.25 (6.19) units, respectively. Soil available P increased in both pyrolyzed and unpyrolyzed PL treatments (by 8.53 mg P kg−1, on average). Clover yields only increased in treatments with amendments that provided more available P and increased the pH. The addition of DBC increased soil total C (30.3%). Both biochars added to the soil surface exhibited little movement through the soil profile (2 to 4 cm). In this study, the pyrolysis of manures emerged as an option for reducing waste volume from the farming industry. Manure biochars proved useful at low rates for enhancing crop yields (PLBC) and storing C in the soil (DBC).
]]>Agronomy doi: 10.3390/agronomy14030591
Authors: Pongsakorn Sunvittayakul Passorn Wonnapinij Pornchanan Chanchay Pitchaporn Wannitikul Sukhita Sathitnaitham Phongnapha Phanthanong Kanokpoo Changwitchukarn Anongpat Suttangkakul Hernan Ceballos Leonardo D. Gomez Piya Kittipadakul Supachai Vuttipongchaikij
Cassava (Manihot esculenta Crantz) is a key industrial crop in Southeast Asia and a staple for food security in Africa, owing to its resilience and efficiency in starch production. This study aims to unravel the genetic determinants of specific cassava root crown traits, utilizing 3D modeling for yield-related attributes and root crown morphology. Phenotypic analysis of 130 partially inbred lines and their six parental lines from Thai commercial varieties revealed a range of root traits within populations showcasing robust correlations among various traits, particularly root size parameters and root weight. Genotyping-by-sequencing yielded a total of 29,361 SNP markers identified within the nuclear genome of cassava and shared across all genotypes. Genome-Wide Association Studies (GWAS) of these 136 genotypes identified 23 significant SNPs for six out of 11 root crown traits, including 3D root angle, 3D surface area, root number, 3D crown diameter, root weight, and 3D volume. We found one shared significant SNP between 3D crown diameter and root weight, and another shared SNP between root weight and 3D volume. Two closely linked SNPs were identified for 3D volume, root weight, and 3D surface area. Linkage disequilibrium (LD) analysis for each pair of SNP markers indicated the linkage decay point at approximately 60 kb. Based on LD decay and available transcriptome data, candidate gene identification highlighted 29 genes associated with five traits, providing an understanding of the genetic basis of cassava root crown traits. Our findings offer novel insights into cassava storage root traits as well as data for marker development and candidate gene identification.
]]>Agronomy doi: 10.3390/agronomy14030590
Authors: Yanchao Yuan Ningning Zhou Shuaishuai Bai Feng Zeng Chunying Liu Yuxi Zhang Shupeng Gai Weiling Gai
The brief longevity of tree peony blossoms constrains its ornamental value and economic worth. Gibberellins (GAs) are crucial in the modulation of flower senescence, and GA 20-oxidase (GA20ox), GA 3-oxidase (GA3ox), and GA 2-oxidase (GA2ox) catalyze the synthesis and deactivation of bioactive GAs. In Paeonia ostii, a total of three PoGA20ox, ten PoGA3ox, and twelve PoGA2ox proteins were identified and comprehensively analyzed. The analysis of the gene structures, conserved domains, and motifs revealed structural similarities and variances among the GA20ox, GA3ox, GA2ox-A, and GA2ox-B subfamilies. The synteny analysis indicated a scarcity of collinear blocks within the P. ostii genome, with no tandem or whole-genome duplication/segmental duplications found in PoGAoxs. The investigation into the binding of transcription factors to PoGAox promoters and the assessments of the expression levels suggest that PoGA2ox1 and PoGA2ox8.1 are promising candidate genes implicated in the regulation of floral senescence. Further, Pos.gene61099 (BPC6) and Pos.gene61094 (CIL2) appear to modulate PoGA2ox1 transcription in a positive and negative manner, respectively, while Pos.gene38359 (DDF1) and Pos.gene17639 (DREB1C) likely enhance PoGA2ox8.1’s expression. This study lays a foundation for an in-depth understanding of PoGAox functions and the development of strategies to delay flower senescence in tree peony.
]]>Agronomy doi: 10.3390/agronomy14030589
Authors: Michael Moustakas Anelia Dobrikova Ilektra Sperdouli Anetta Hanć Julietta Moustaka Ioannis-Dimosthenis S. Adamakis Emilia Apostolova
High light (HL) intensity has a substantial impact on light energy flow and partitioning within photosynthetic apparatus. To realize the impact of HL intensity on zinc (Zn) tolerance mechanisms in clary sage (Salvia sclarea L., Lamiaceae) plants, we examined the effect of the altered chlorophyll and nutrient uptake under excess Zn supply on the response mechanism of photosystem II (PSII) photochemistry. Eight-week-old clary sage plants were treated with 5 μM Zn (control) or 900 μM Zn in Hoagland nutrient solution. Leaf elemental analysis for Zn, Mn, Mg, and Fe was performed by inductively coupled plasma mass spectrometry (ICP-MS), whereas PSII functioning under HL was evaluated by chlorophyll fluorescence imaging analysis. Exposure of S. sclarea plants to 900 μM Zn increased leaf Zn accumulation and decreased leaf Mg and chlorophyll. The decreased non-photochemical quenching (NPQ) provided evidence of the photoprotection offered by the smaller light-harvesting antennae due to the reduced chlorophyll. The increased Mn after Zn exposure corresponded with higher efficiency of the oxygen-evolving complex (OEC) that was significantly correlated with the maximum efficiency of photosystem II (PSII) photochemistry (Fv/Fm). An increased electron transport rate (ETR) coincided with increased leaf Fe, which is known to play a vital role in the enzymes engaged in ETR. The decreased (32%) NPQ after an 8-day exposure to Zn caused an increased (10%) quantum yield of non-regulated energy loss in PSII (ΦNO), indicative of an increased singlet oxygen (1O2) production. It is suggested that the decreased NPQ induced acclimation responses of clary sage plants to HL and excess Zn by increasing 1O2 production. The reduced (18%) excess excitation energy (EXC) at PSII and the increased (24%) quantum yield of PSII photochemistry (ΦPSII) and ETR indicated improved photosynthetic efficiency under excess Zn and HL intensity. Therefore, the exposure of medicinal plants to excess Zn not only boosts their photosynthetic efficiency, enhancing crop yields, but can also improve Fe and Zn content, ameliorating the human health deficiency of these two essential micronutrients.
]]>Agronomy doi: 10.3390/agronomy14030588
Authors: Bruno F. Fregonezi Anderson E. S. Pereira Josué M. Ferreira Leonardo F. Fraceto Diego G. Gomes Halley C. Oliveira
Water deficit (WD) promotes great losses in agriculture, and the development of new sustainable technologies to mitigate the effects of this stress on plants is essential. This study aimed to evaluate the morphophysiological and biochemical alterations induced by the priming of tomato seeds with different formulations in plants under field capacity and WD conditions. In the first experiment, the treatments consisted of nanoparticles of alginate/chitosan and chitosan/tripolyphosphate containing gibberellic acid (GA3) in different concentrations (0.5, 5, and 50 µg mL−1 GA3), in addition to control with deionized water. The alginate/chitosan (5 µg mL−1 GA3) provided the greatest gains in plant growth under field capacity. In addition, under WD this treatment reduced damage to photosystem II (−14%), stomatal conductance (−13%), and water loss (−38%) and increased the instantaneous carboxylation efficiency (+24%) and intrinsic water use efficiency (+12%). In the second experiment, the treatments were alginate/chitosan nanoparticles containing GA3 (NPGA3 5 µg mL−1), free GA3 (GA3 5 µg mL−1), nanoparticles without GA3 (NP), deionized water (WATER), and non-primed seeds (CONT). Under WD, GA3 and CONT maintained plant growth and lost water rapidly, reducing stomatal conductance (−87%) and net photosynthesis (−69%). In contrast, NPGA3 decreased leaf area (−44%) and increased root-to-shoot ratio (+39%) when compared to GA3, reducing water loss (−28%). Activation of protective mechanisms (e.g., superoxide dismutase and catalase activities) by WATER, NPGA3, and NP treatments also resulted in lower susceptibility to WD compared to CONT and GA3. The results highlight the positive effect of seed priming on plant response to WD, which was enhanced by the use of nanoencapsulated GA3.
]]>Agronomy doi: 10.3390/agronomy14030587
Authors: Biao Liu Wei Chen Zhen Wang Zhaohui Guo Yongmei Li Lijuan Xu Minxi Wu Hongmei Yin
Nitrogen loss is an unavoidable problem during organic waste composting, while exogenous microbial inoculation is a promising strategy for reducing nitrogen loss and improving compost quality. This study was designed to probe available nitrogen levels, bacterial community composition, and the levels of nitrogen functional genes present when composting cattle manure with or without the addition of Bacillus coagulans X3. Bacterial supplementation was associated with the prolongation of the thermophilic stage and improved maturity of the resultant compost. At the maturity stage, samples to which B. coagulans X3 had been added exhibited significant increases in ammonium nitrogen, nitrate nitrogen, and total nitrogen levels. The dominant bacterial phyla observed in these composting samples were Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteriota, and Chloroflexi. B. coagulans X3 addition resulted in significant increases in relative Firmicutes abundance during the thermophilic and cooling stages while also increasing amoA and nosZ gene abundance and reducing nirS gene levels over the course of composting. Together, these data suggest that B. coagulans X3 supplementation provides an effective means of enhancing nitrogen content in the context of cattle manure composting through the regulation of nitrification and denitrification activity.
]]>Agronomy doi: 10.3390/agronomy14030586
Authors: Zhengyan Miao Haipeng Shang Mengjie Lin Rui Song Jiashuai He Xinmei Li Leikang Sun Xiaoyong Li Hangzhao Guo Yuxia Li Rongfa Li Quanjun Liu Zhibo Feng Xucun Jia Qun Wang
Interplanting is an efficient method of improving nutrient utilization. However, the impact of intraspecific interplanting on rhizosphere microbial nitrogen cycling needs to be studied further. In this study, two corn cultivars were selected as the materials: Zhengdan958 (ZD958, high nitrogen use efficiency) and Denghai3622 (DH3622, low nitrogen use efficiency). Three planting patterns (interplanting, ZD958 monocropping, and DH3622 monocropping) were set up to study the effects of interplanting on crop growth and rhizosphere microbial nitrogen cycle function under two nitrogen levels: low nitrogen (140 kg N ha−1) and normal nitrogen (280 kg N ha−1). The results showed that the grain yield and nitrogen content in interplanting were significantly increased due to an enhanced leaf area index and root dry weight. The nitrogen accumulation and nitrogen use efficiency were enhanced by 8.14% and 19.38% in interplanting, which resulted in reductions in NH4+ and NO3− content in the rhizosphere. Interplanting enhanced rhizosphere nitrogen cycling processes; nitrification, denitrification, and nitrate reduction were increased. This study demonstrated that interplanting promotes corn nitrogen acquisition from the soil and indirectly regulates rhizosphere microbial function. These findings imply that the intraspecific interplanting of crops with appropriate functional traits is a promising approach to establishing diversified, productive, and efficient resource utilization ecosystems.
]]>Agronomy doi: 10.3390/agronomy14030585
Authors: Xiaolei Gao Ying Yang Jiawei Ye Huan Xiong Deyi Yuan Feng Zou
Cytoplasmic male sterility (CMS) plays a crucial role in the utilization of heterosis. The petaloid anther abortion in oil tea (Camellia oleifera Abel.) constitutes a CMS phenomenon, which is of great value for the hybrid breeding of oil tea. However, as the mechanism of its CMS is still poorly understood, it is necessary to study the cytology and physiological characteristics of anther abortion. In this study, a C. oleifera cultivar, Huashuo (HS), and its petalized CMS mutant (HSP) were used as materials to explore this mechanism. Compared with HS, cytological analysis demonstrated that HSP showed early-onset tapetum programmed cell death (PCD) and an organelle disorder phenotype during the tetrad stage. In HSP, anthers exhibited elevated levels of calcium deposition in anther wall tissues, tapetum layers, and microspores, and yet calcium accumulation was abnormal at the later stage. The contents of hydrogen peroxide and MDA in HSP anthers were higher, and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were lower than those of HS, which resulted in an excessive accumulation of reactive oxygen species (ROS). Real-time quantitative PCR confirmed that the transcription levels of CoPOD and CoCAT genes encoding key antioxidant enzymes in HSP were downregulated compared with HS in early pollen development; the gene CoCPK, which encodes a calcium-dependent protein kinase associated with antioxidase, was upregulated during the critical period. Thus, we suggest that excessive ROS as a signal breaks the balance of the antioxidant system, and along with an abnormal distribution of calcium ions, leads to the early initiation of PCD in the tapetum, and ultimately leads to pollen abortion for HSP. These results lay a cytological and physiological foundation for further studies on the CMS mechanism, and provide information for breeding male-sterile lines of C. oleifera.
]]>Agronomy doi: 10.3390/agronomy14030584
Authors: Jiufu Luo Zhongxin Luo Wen Li Wenbo Shi Xin Sui
The co-allocation of photovoltaic arrays with crops presents a promising strategy to mitigate the conflict between photovoltaics and agricultural land. However, there is a notable lack of quantitative research on the impact of agrivoltaic system on land quality in fragile areas. In this study, peanuts (Arachis hypogaea) and ryegrass (Lolium perenne) were cultivated in photovoltaic array in the dry–hot valley of southwest China, with an off-site native land serving as the control. Sixteen soil physicochemical and biochemical parameters were measured in the gap and under-panel and control area. Results demonstrated that the agrivoltaic system significantly enhanced soil moisture, organic carbon, nitrogen–phosphorus–potassium nutrients, microbial biomass, and urease activity. It also led to varying degrees of increase in soil pH and electrical conductivity, along with reduced soil sucrase and phosphatase activity. In comparison to the control, the agrivoltaic system notably improved soil quality and multifunctionality. Specially, gap cultivation had a more pronounced positive impact on soil quality than under-panel cultivation, and the cultivation of peanuts had a greater effect on soil quality and multifunctionality improvement than ryegrass. This study provides fundamental data to support the improvement of land quality in photovoltaic developed regions, and to alleviate the conflict between photovoltaics and agricultural land.
]]>Agronomy doi: 10.3390/agronomy14030583
Authors: Wei Tang Ziguang Li Haipeng Guo Boyu Chen Tingru Wang Fuhong Miao Chao Yang Wangdan Xiong Juan Sun
Although weeds can be inhibited by high planting densities, canopy shading, elemental balance and soil microbial recruitment are not yet adequately considered when measuring competitive effects on weed control. The effects of oat (Avena sativa) planting density (60 to 600 plants m−2) on the biomass and shoot element balance of oat and weeds were evaluated in a field experiment. The shift in the microbial community of the dominant weed species was examined in a pot experiment by growing the weed alone and in competition with 360 oat plants m−2 (recommended planting density) under greenhouse conditions. Increasing oat planting density beyond 360 plants m−2 did not improve oat forage yield or weed suppression. Compared to 60 plants m−2, the biomass of broadleaf and grass weeds decreased by 1122% and 111%, respectively, at a density of 360 plants m−2, while oat forage biomass increased by 60% and leaf area index by 24%. The improved canopy properties suppressed competing weeds through increased shading. Typically, the C:N and C:P ratios of shoots of Echinochloa crus-galli and Digitaria sanguinalis were higher than those of Portulaca oleracea and Chenopodium album. At high planting densities, E. crus-galli and D. sanguinalis exhibited high P contents and low N:P ratios, suggesting a limited supply of N nutrients for growth. Soil bacterial community assay showed that the composition of microbial communities of the two grass weeds were shaped by the presence of oat competition, which also considerably depleted several important functional microbes associated with nutrient cycling in the weeds’ rhizosphere. These results highlight that increased crop density significantly improves the crop competitive advantage over weeds through increased shading, reduced elemental balance, and beneficial microorganisms of weeds, thereby reducing the need for herbicides or physical weed control in oat cropping system.
]]>Agronomy doi: 10.3390/agronomy14030582
Authors: Haile Tewolde Thomas R. Way Normie Buehring Johnie N. Jenkins
Poultry litter (PL) is known to have residual effects on crop productivity long after applications cease. Whether this advantage is greater if applied by subsurface vs. surface broadcast is unknown. The objective of this study was to determine whether the residual benefit of PL to corn and cotton production is greater if applied in subsurface bands vs. surface broadcast and identify PL components contributing to this effect. The residual effect of PL applied by the two methods or synthetic nitrogen (sN) at seven plant available N rates (0–292 kg ha−1 yr−1) in 2014–2015 was tested on corn and cotton in 2016–2019. Corn was grown without applying PL or sN in 2016, and cotton was grown in 2017–2019 after applying 90 kg ha−1 yr−1 sN to all plots. Corn produced 40% greater grain and cotton produced 29% more lint yield due to residuals from PL than sN. Residuals from PL distinctly increased cotton leaf K over sN regardless of the method of application. Corn and cotton yield benefits from PL residual were greater if applied by subsurface banding vs. surface broadcast. This difference diminished with time. The overall results show PL components persist in the soil for up to 4 years and affect corn and cotton production, but this persistence is greater if the PL is applied by subsurface banding. This study identified K as the key PL nutrient that persisted in the soil and benefited cotton yield 4 years after the last application.
]]>Agronomy doi: 10.3390/agronomy14030581
Authors: Shibiao Cai Bangyu Zheng Zhiyuan Zhao Zhaoxia Zheng Na Yang Bingnian Zhai
Understanding the stoichiometry of extracellular enzymes in soil, particularly in relation to nutrient acquisition (e.g., carbon, nitrogen, phosphorus), provides valuable insights into microorganisms’ resource requirements. This study investigates the metabolic constraints of soil microorganisms in response to different growth stages of apple trees under various soil management practices. A 14-year long-term experiment with a split-plot design was conducted, where the main plots received different cover crop treatments (bare vs. cover crop), and subplots were subjected to four fertilizer treatments (CK, M, NPK, MNPK). The significant main and interactive effects of cover crops, fertilizer treatment, and growth period on soil nutrients were observed (p < 0.001). Both cover crop and fertilizer treatments significantly increased the soil organic matter content, with implications for orchard resilience to drought. However, the cover factor alone did not notably influence soil carbon–nitrogen ratios or microbial communities. Microbial carbon limitations were driven by soil water dynamics and microbial biomass, while microbial phosphorus limitations were closely linked to total nitrogen levels. The results underscore the combination of cover crops and MNPK fertilizer-enhanced soil nutrient levels and enzyme activities, mitigating microbial carbon and phosphorus limitations. These findings suggest practical strategies for optimizing fertilization practices to improve soil fertility and address nutrient constraints in orchard ecosystems.
]]>Agronomy doi: 10.3390/agronomy14030579
Authors: Athakorn Promwee Sukimplee Nijibulat Hien Huu Nguyen
The rising adoption of agricultural technologies such as the Internet of Things (IoT) or “smart farming” aims to boost crop production in terms of both quantity and quality. This study compares the benefits of a smart farm employing an IoT-based hydroponic system with those of a conventional hydroponic farm, using Chinese cabbage (Brassica pekinensis L.) as the experimental crop. Our primary objective was to automate environmental monitoring, achieving pH level and electrical conductivity (EC) maintenance through smartphone or computer interfaces for nutrient and acid–base solution adjustments. Additionally, we evaluated plant growth and crop quality, finding superior results with the smart hydroponic system. On average, there were substantial increases in various parameters, including total fresh weight (27.14%), total dry weight (48.90%), plant height (11.14%), stem diameter (32.89%), leaf area (94.30%), leaf width (32.36%), leaf length (38.12%), and chlorophyll content (22.73%). Nitrate accumulation in the edible parts of Chinese cabbage remained within safe limits for both systems, reflecting careful nutrient management. These findings highlight the potential of IoT-based technology in enhancing productivity and quality in hydroponic farming, marking a significant step towards revolutionizing traditional agricultural practices for more efficient crop production systems.
]]>Agronomy doi: 10.3390/agronomy14030580
Authors: Shuqi Jiang Jiankui Yu Shenglin Li Junming Liu Guang Yang Guangshuai Wang Jinglei Wang Ni Song
This research provides a comprehensive analysis of the spatiotemporal evolution of the regional cropping structure and its influencing factors. Using Landsat satellite images, field surveys, and yearbook data, we developed a planting structure extraction model employing the classification regression tree algorithm to obtain data on the major crop cultivation and structural characteristics of Alar reclamation from 1990 to 2023. A dynamic model and transfer matrix were used to analyze temporal changes, and a centroid migration model was used to study spatial changes in the cropping structure. Nonparametric mutation tests and through-traffic coefficient analysis were utilized to quantify the main driving factors influencing the cropping structure. During the period of 1990–2023, the cotton area in the Alar reclamation region expanded by 722.08 km2, while the jujube exhibited an initial increase followed by a decrease in the same period. The primary reasons are linked to the cost of purchase, agricultural mechanization, and crop compatibility. In the Alar reclamation area, cotton, chili, and jujube are the primary cultivated crops. Cotton is mainly grown on the southern side of the Tarim River, while chili cultivation is concentrated on the northern bank of the river. Over the years, there has been a noticeable spatial complementarity in the distribution and density of rice and cotton crops in this region. In the Alar reclamation, the main factors influencing the change in cultivated land area are cotton price, agricultural machinery gross power, and population. Consequently, implementing measures such as providing planting subsidies and other policy incentives to enhance planting income can effectively stimulate farmers’ willingness to engage in planting activities.
]]>Agronomy doi: 10.3390/agronomy14030578
Authors: Taotao Zhao Xinqiang Zhu Hongshan Yang Yonggang Wang Feifan Leng Xiaoli Wang
Volatile components are one key factor in sample identification, differential analysis, quality control and origin traceability. In order to identify and analyze the differences in volatile substances in different alfalfa seeds, this study used gas chromatography–ion mobility spectrometry (GC-IMS), combined with the Gallery Plot plug-in, and PCA, PLS-DA and other analysis methods. In this way, a comprehensive analysis of volatile components in 10 alfalfa seeds, including aerospace varieties, was conducted. A comparative analysis of the characteristics of different sample compounds using topographic maps and fingerprints led to isolation of 48 kinds of 54 volatile compounds. Among them, esters (9 types), olefins (8 types), ketones (8 types), alcohols (6 types) and aldehydes (6 types) were found to be the most abundant volatile compounds in alfalfa seeds. At the same time, PCA and PLS-DA analysis models showed that esters, ketones and alcohols were the main volatiles causing the differences among alfalfa seeds. Among them, the content of various substances in the ZT2 and ZT3 aerospace varieties were higher than that of other varieties, while the types and contents of volatiles in ZT1, ZM2 and GN3 were relatively low. Therefore, in combination with the differences in maturity of each sample, the 10 varieties of alfalfa were finally divided into three categories, and the varieties of the same series were basically classified into one category. This provides a basis and convenience for future seed screening, identification, traceability and forage breeding.
]]>Agronomy doi: 10.3390/agronomy14030577
Authors: Ruowen Qiang Meng Wang Qian Li Yingjie Li Huixian Sun Wenyu Liang Cuilan Li Jinjing Zhang Hang Liu
Denitrification is a key process in soil available nitrogen (N) loss. However, the effects of different water-saving irrigation systems on soil N components and denitrifying bacterial communities are still unclear. In this study, quantitative fluorescence PCR and Illumina MiSeq sequencing were used to investigate the effects of three main irrigation systems, conventional flooding irrigation (FP), shallow buried drip irrigation (DI), and mulched drip irrigation (MF), on the abundance, community composition, and diversity of soil nirK- and nirS-type denitrifying bacteria in the semi-arid area of Northeast China, and to clarify the driving factors of nirK- and nirS-type denitrifying bacterial community variations. The results showed that, compared with FP, MF significantly increased soil moisture, alkaline hydrolyzed nitrogen (AHN), nitrate nitrogen (NO3−-N), non-acid hydrolyzed nitrogen (AIN), and amino sugar nitrogen (ASN), but significantly decreased the contents of ammonium nitrogen (NH4+-N) and acid hydrolyzed ammonium nitrogen (AN). The irrigation system changed the relative abundance of the dominant genera of denitrifying bacteria, DI and MF significantly increased nitrate reductase (NR) and nitrite reductase (NiR) activities, and MF significantly increased the diversity of nirK- and nirS-type denitrifying bacteria but significantly decreased the richness. The community structure of nirK- and nirS-type denitrifying bacteria was significantly different among the three irrigation systems. NO3−-N was the main driving factor affecting the community structure of nirS-type denitrifying bacteria, and moisture significantly affected the community structure of nirK-type denitrifying bacteria. DI and MF significantly increased the abundance of nirK- and nirS-type denitrifying bacteria and also increased the abundance ratio of nirS/nirK genes. Therefore, although DI and MF significantly increased the abundance of denitrifying microorganisms, they did not lead to an increase in the N2O emission potential.
]]>Agronomy doi: 10.3390/agronomy14030576
Authors: Bolin Wu Jiqing Peng Hanyu Fu Fengxia Shao Song Sheng Sen Wang
The biosynthesis and distribution of lignans in medicinal plants, particularly in Schisandra sphenanthera, hold significant pharmacological importance. This study bridges the knowledge gap in understanding the tissue-specific biosynthesis and distribution of these compounds, with a focus on Gomisin J. Our phytochemical analysis revealed a distinct accumulation pattern of Gomisin J, predominantly in the roots, contrasting with the distribution of Pregomisin and Dihydroguaiaretic acid. This finding highlights the roots’ unique role in lignan storage and biosynthesis. Further, differential gene expression analysis across various tissues illuminated the biosynthetic pathways and regulatory mechanisms of these lignans. Utilizing Weighted Gene Co-expression Network Analysis (WGCNA), we identified the MEtan module as a key player, strongly correlated with Gomisin J levels. This module’s in-depth examination revealed the crucial involvement of four cytochrome P450 (CYP) enzymes and eight transcription factors. Notably, the CYP genes DN6828 and DN2874-i3 exhibited up-regulation in roots across both male and female plants, while DN51746 was specifically up-regulated in male roots, indicating a potential gender-specific aspect in Gomisin J biosynthesis. Comparative analysis with functionally characterized CYP71A homologs suggests these CYP genes might be involved in distinct biosynthetic pathways, including terpenoids, alkaloids, and phenylpropanoids, and potentially in lignan biosynthesis. This hypothesis, supported by their more than 55% identity with CYP71As and strong correlation with Gomisin J concentration, opens avenues for novel discoveries in lignan biosynthesis, pending further functional characterization. Our research provides a comprehensive understanding of the genetic and metabolic mechanisms underlying the tissue-specific distribution of lignans in Schisandra sphenanthera, offering valuable insights for their pharmacological exploitation.
]]>Agronomy doi: 10.3390/agronomy14030575
Authors: Mirko La Iacona Sara Lombardo Giovanni Mauromicale Aurelio Scavo Gaetano Pandino
The manipulation of allelopathic mechanisms, such as the isolation of plant allelochemicals for bioherbicide production, is currently providing a new tool for weed management methods of reducing or potentially eliminating the use of synthetic herbicides. In Mediterranean agroecosystems, wild Asteraceae are the prevalent taxa, likely due to their allelopathic activity. Hence, the objective of this study was to evaluate the allelopathic effects of the aqueous extracts obtained from milk thistle [Silybum marianum (L.) Gaertn], wild cardoon (Cynara cardunculus L. var. sylvestris) and purple milk thistle (Galactites tomentosus Moench) on the seed germination, mean germination time, and seedling growth of three target weeds: Portulaca oleracea L., Taraxacum officinale (Weber) ex Wiggers and Anagallis arvensis L. The total polyphenol (TP), flavonoid (TF), flavonol (TFL), and phenolic acid (TPA) content in the aqueous extracts was also evaluated. Overall, the allelopathic effects were species-dependent and root length was the most affected parameter. All extracts completely inhibited root development in P. oleracea. Averaged over target weeds, C. cardunculus extract had the greatest allelopathic activity, followed by G. tomentosus and by S. marianum. In particular, C. cardunculus reduced seed germination by over 50% and increased the mean germination time by 154%, likely due to the highest TP (13.2 g kg−1 DM) and TPA (11.4 g kg−1 DM) content, compared to the other Asteraceae species. These results provide evidence of the phytotoxic activity of the three wild Asteraceae members and suggest their possible future exploitation as potential bioherbicides for sustainable weed management.
]]>Agronomy doi: 10.3390/agronomy14030574
Authors: Md. Shahidul Haque Bir Md. Arshad Ali Most Mohshina Aktar Kee Woong Park Muhammad Shahbaz Khim Phin Chong Muhammad Shafiq Shahid Olga Panfilova Gabrijel Ondrasek
Increase in the concentration of atmospheric greenhouse gases significantly contributes to global warming, representing a substantial challenge for crop production. The study was conducted to determine the growth competition between rice (Oryza sativa) and barnyardgrass (Echinochloa oryzicola) under (i) different cropping patterns and (ii) elevated air temperatures in phytotrons under field condition, at two plant densities (4 and 16 plants per pot). Rice and barnyardgrass were planted with varying cropping patterns (rice: barnyardgrass mixture proportions); 100:0, 75:25, 50:50, 25:75 and 0:100. Air temperatures were maintained in phytotrons as follows: Ambient–A (Control), A +0.8 °C, A +1.9 °C and A +3.4 °C. Plant attributes such as plant height, number of effective tillers, shoot dry weight and grain yield of rice were recorded in this study in the rice/barnyardgrass mixture proportions in the order of 100:0 > 75:25 > 50:50 > 25:75. The highest rice grain yield (37.7 g/pot) was recorded in the monoculture (100:0 rice/barnyardgrass) under ambient temperature, whereas the lowest rice grain yield (0.3 g/pot) was recorded at the 25:75 rice/barnyardgrass mixture proportion under ambient +3.4 °C. The increase in temperature had a significant impact on growth, number of tillers and shoot dry weight of both rice and barnyardgrass plants and followed the order of ambient +3.4 °C > ambient +1.9 °C > ambient +0.8 °C > ambient. However, higher temperature negatively affected the yield of rice and resulted in a substantial decrease in the grain yield. Barnyardgrass showed the highest plant characteristics when grown alongside rice compared to the growth in monoculture. This indicates that barnyardgrass was highly competitive when grown under interspecific competition compared to an intraspecific competition. In contrast, rice grew better in monoculture than in mixture with barnyardgrass.
]]>Agronomy doi: 10.3390/agronomy14030573
Authors: Wei Hu Zhouming Gao Xiaoya Dong Jian Chen Baijing Qiu
Contact electrification has attracted interest as a mechanism for generating electrical charges on surfaces. To explore the factors contributing to electrification by droplets impacting the leaf surface, high-speed image capture and current measurements were used to quantitatively characterize the electrical response under different droplet parameters and leaf surface conditions. Upon impact and rebound from the leaf surface, neutral droplets acquire a positive charge. While this electrification phenomenon has been observed previously, there has been limited understanding of the parameters influencing the extent of droplet charging. In this study, we examine the effects of four parameters (droplet size, impact velocity, droplet ion concentration, and various leaf surfaces) on the electrical response signal. The results indicate that this electrification phenomenon is contingent upon the droplet–leaf contact area and droplet ion concentration. We propose a theoretical model based on the electric double layer to elucidate the electrification process.
]]>Agronomy doi: 10.3390/agronomy14030572
Authors: Shining Han Yanxi Liu Anor Bao Tongtong Jiao Hua Zeng Weijie Yue Le Yin Miao Xu Jingmei Lu Ming Wu Liquan Guo
The COP9 signalosome (CSN) is a conserved protein complex, with CSN1 being one of the largest and most important subunits in the COP9 complex. To investigate the N-terminus function of OsCSN1, we edited the N-terminus of OsCSN1 and found that the mutant of OsCSN1 with 102 amino acids missing at the N-terminus showed insensitivity to red light in terms of the embryonic sheath, stem elongation, and main-root elongation. Moreover, the mutant was able to produce, develop, and bear fruit normally. The research results indicate that OsCSN1 is a negative regulator of stem elongation in rice seedlings regulated by red light. Under red-light treatment, OsCSN1 assembles into CSN, which degrades SLR1 through de NEDDylation, affecting PIL11 activity and ultimately inhibiting stem elongation. OsCSN1 also plays an important regulatory role in the inhibition of rice embryonic sheath elongation under red light. By regulating the degradation of SLR1 and PIL14 through the ubiquitin/26S protease pathway, the elongation of the embryonic sheath is ultimately inhibited. OsCSN1 forms a COP9 complex and is modified with RUB/NEDD8 of the E3 ligase of CUL1 to promote the degradation of SLR1 and PIL14, ultimately affecting the elongation of the embryonic sheath. The regulatory domain is located at the N-terminus of CSN1.
]]>Agronomy doi: 10.3390/agronomy14030571
Authors: Jianwei Hou Cunfang Xing Jun Zhang Qiang Wu Tingting Zhang Junmei Liang Hao An Huiqing Lan Yu Duan
The nutrient availability of carbon (C), nitrogen (N), and phosphorus (P) has been decreasing due to a decline in the biological function of yellow soil, limiting potato yield (PY). Increasing biochar or organic fertilizer input is an effective way to improve soil microbiological fertility. However, indexes to regulate soil microbiological fertility using biochar and organic fertilizer individually or in combination and these indexes’ associations with PY remain unclear. In this study, four fertilization strategies were developed using the nutrient balance method: CK (recommended NPK fertilization), BC (NPK + biochar), OF (NPK + organic fertilizer), and BF (NPK + 1/2 biochar + 1/2 organic fertilizer). Using different fertilization strategies, the eco-stoichiometry characteristics of the soil microbial biomass and enzyme activity; the bioavailability of C, N, and P; and the differences in PY were investigated, and the direct and indirect effects of these factors on PY were determined over a two-year period. The results showed that exogenous organic matter input could considerably affect the stoichiometric ratios of soil microbial biomass; C; N; P; the stoichiometric ratios of C-converting, N-converting, and P-converting enzyme activities (expressed as BG+CBH, NAG+LAP, and AP, respectively); and the integrated enzyme index (IEI). The IEI was the highest in BF, followed by OF, BC, and CK. A significant positive correlation was found between the microbial biomass C, N, and P and their corresponding converting enzyme activities (p < 0.05). The ln(BG+CBH):ln(NAG+LAP), ln(BG+CBH):lnAP, and ln(NAG+LAP):lnAP ratios were all higher than 1:1, but they approached 1:1 in the order of CK-BC-OF-BF. Compared to soil C and N, P-converting enzyme activity was the primary limiting factor for soil nutrient conversion in the study area. BF was less restricted by P and more balanced in its nutrient ratio. The microbial biomass C:N:P could affect PY in eight ways. (1) Microbial biomass C:N directly decreased PY, and microbial biomass C:P indirectly increased PY. (2) It could decrease C-converting enzyme activity, (3) decrease N availability to increase C-converting enzyme activity, (4) decrease P availability, or (5) decrease P availability to decrease the soil C:P-converting enzyme activity ratio. Microbial biomass N:P indirectly increased PY (6) by increasing the soil C:P-converting enzyme activity ratio, (7) by increasing C-converting enzyme activity, or (8) by increasing N availability to increase C-converting enzyme activity. Thus, BF is an effective strategy for regulating the soil microbiological fertility index; enhancing C, N, and P nutrient conversion; and increasing PY. The input of exogenous organic matter can alter the stoichiometric ratios of soil microbial biomass C, N, and P; the stoichiometric ratios of C-converting, N-converting, and P-converting enzyme activities; and nutrient availability, thus regulating PY. Microbial biomass N:P and soil C:P-converting enzyme activity ratios influence PY the most.
]]>Agronomy doi: 10.3390/agronomy14030570
Authors: Azizullah Khalili Ahlam Khalofah Aketi Ramesh Mahaveer P. Sharma
Nitrogen (N) and sulfur (S) are essential nutrient elements, and their deficiency affects crop growth, productivity, and nutrient uptake due to their multifaceted role in plant metabolism, which has been well documented. Therefore, agricultural management strategies that can overcome these deficiencies are the need of the hour. In this context, a study was undertaken with the objective to assess the impacts of N and S applications, either basally or through split application (12.5, 25 and 50 kg ha−1), on the nutrient uptake, productivity, use efficiency, and micronutrient content status in soybean seeds, and also the change in soil nutrient zinc (Zn) and iron (Fe) content at different critical stages of soybean crop growth. The field trial was conducted utilizing a randomized complete-block design, and comprised fourteen treatments with varying N and S quantities. N and S were applied through basal and split applications in different combinations. The salient findings indicated that the highest seed, straw yield, N, and S uptake were obtained with the application of N25+25, S25+25, and did not significantly vary with N25+25, S12.5+12.5, N50, and N25+S50. The highest N use efficiency was recorded with the application of N25+S50, and S use efficiency with the application of N25+25, S25+25. The split application of N and S as N25+25, S25+25 significantly increased soil Zn and Fe content at R2 and R5 stages of soybean crop growth, as well as seed Zn and Fe uptake. It can be concluded that the basal and split application of N and S at the rate of 25 kg ha−1 can improve soybean productivity through increased mobilization and assimilation by plants. The findings indicated that applying N and S separately, with 25 kg ha−1 each basally and at the R2 stage resulted in the highest nutrient uptake, and seed and straw yields. The nutrient use efficiencies, along with Zn and Fe uptake by seeds, exhibited noticeable improvements with this split application approach compared to the control. Furthermore, the soil Zn and Fe contents also experienced enhancements due to the split application of both Nand S fertilizers. These results underscore the potential benefits of temporally adopting optimized fertilizer application strategies to maximize agricultural productivity while ensuring efficient nutrient utilization and soil health maintenance. Further research and field trials could provide deeper insights into the long-term impacts and scalability of this approach across different crop varieties and environmental conditions.
]]>Agronomy doi: 10.3390/agronomy14030568
Authors: Xianglan Su Yixia Cai Bogui Pan Yongqi Li Bingquan Liu Kunzheng Cai Wei Wang
Pot and field trials were conducted to explore the combined effect of biochar (BC) with topdressing silicon (Si) on Cd uptake by rice and grain yield in Cd-contaminated paddy soil. The treatments, including BC applied before transplanting (TBC), topdressing Si applied in the soil at the jointing stage (JSi) and BC combined with topdressing Si (TBC + JSi), were designed in a complete random block, and treatment without application of BC and Si was used as a control (CK). Results showed that Cd concentration in milled rice treated with TBC + JSi was decreased by 34.62%, 22.73% and 10.53%, respectively, when compared to CK, TBC and JSi, with the concentration being only 0.17 mg·kg−1. At rice maturity, available Cd in the soil was reduced by 7.98% (TBC), 4.76% (JSi) and 6.02% (TBC + JSi) when compared with CK, while the concentrations of total Cd were 32.07% (TBC), 27.85% (JSi) and 35.44% (TBC + JSi) higher than CK. Moreover, BC and Si increased the Cd sequestrated by leaves markedly, especially for TBC + JSi, which was much higher than TBC and JSi. Therefore, the transfer of Cd from leaf to milled rice was greatly decreased by TBC + JSi. In addition, a synergy effect of TBC + JSi on rice yield was also found. Compared with CK, the grain yields of TBC, JSi and TBC+ JSi were increased by 8.35%, 8.20% and 18.74%, respectively. Nutrient contents in soil and rice plants were also elevated by the application of BC and Si to a certain extent; for example, the contents of nitrogen (N), phosphorus (P), potassium (K) and Si in soil treated with TBC + JSi were raised by 8.96–60.03% when compared with CK. Overall, the combined application of BC with topdressing Si not only increases soil nutrients significantly, promotes their uptake by rice and boosts grain yield, but also effectively inhibits Cd transfer and reduces its accumulation in rice, which ultimately guarantees milled rice security. These results also imply that the combined application of biochar with topdressing silicon might be considered as an effective agronomic measure to decrease the milled-rice Cd in Cd-contaminated paddy soil, which would guarantee food security.
]]>Agronomy doi: 10.3390/agronomy14030569
Authors: Xiao Xu Xinyu Wang Sirui Zhou Xumo Huang Pengcheng Liu Bojun Ma Xifeng Chen
OVATE family proteins (OFPs) are a kind of plant-specific transcription factor, which play important roles in the growth and development of plants. Here, we performed a genome-wide investigation of the OFP gene family members in the wild diploid strawberry (Fragaria vesca, 2n = 14), and analyzed their physical and chemical properties, gene structure, phylogeny, expression patterns, and the subcellular localizations of these genes. Fourteen OFP genes from F.vesca were identified. Collinearity analysis showed ten pairs of collinearity between F. vesca and Arabidopsis. Phylogenetic analysis divided FvOFP genes into five different clades. The expression patterns of the FvOFP genes assayed in different tissues of F. vesca by Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) showed that FvOFP1, FvOFP11, FvOFP12, and FvOFP14 were highly expressed in achene and their expression was further verified in the fruits at different developmental stages. Additionally, the subcellular localizations of FvOFP1, FvOFP11, FvOFP12, and FvOFP14 were preliminarily analyzed in tobacco leaves. The results showed clear fluorescent signals in the nucleus. Our results provided a comprehensive understanding of the potential function of FvOFP genes in strawberries.
]]>Agronomy doi: 10.3390/agronomy14030567
Authors: Guillermo Aguilera Nuñez Anders Glimskär Giulia Zacchello Richard M. Francksen Mark J. Whittingham Matthew Hiron
Permanent grasslands cover more than a third of European agricultural land and are important for a number of ecosystem services. Permanent grasslands used for agriculture are broadly separated into agriculturally improved and semi-natural grasslands. High cultural and natural values linked to semi-natural grasslands are well documented. However, in boreal and hemi-boreal agricultural landscapes, less information is available about the areal coverage of improved permanent grasslands and their role for ecosystem service provision and biodiversity. In Sweden, grasslands are administratively separated into semi-natural (i.e., land that cannot be ploughed) or arable (i.e., improved temporary or permanent grassland on land that can be ploughed). We used data from a large-scale environmental monitoring program to show that improved permanent grassland (i.e., permanent grasslands on arable fields) may be a previously unrecognised large area of the agricultural land use in Sweden. We show that improved permanent grasslands together with semi-natural grasslands are both comparable but also complementary providers of a range of ecosystem services (plant species richness, plant resources for pollinators and forage amount for livestock production). However, as expected, semi-natural grasslands with the highest-level AESs (special values) show high species richness values for vascular plants, plants indicating traditional semi-natural management conditions and red-listed species. Improved permanent grasslands on arable fields are likely an underestimated but integral part of the agricultural economy and ecological function in boreal landscapes that together with high nature value semi-natural grasslands provide a broad range of ecosystem services.
]]>Agronomy doi: 10.3390/agronomy14030566
Authors: Partha S. Biswas R. Santelices Rhulyx Mendoza Vitaliano Lopena Juan D. Arbelaez Norvie L. Manigbas Joshua N. Cobb Bertrand Collard Mohammad Rafiqul Islam
The pedigree, bulk, and single-seed descent-based rapid generation advance methods are commonly practiced breeding methods in rice. But the efficiency of these breeding methods in enhancing genetic gain has not been investigated yet. In this study, we compared the pedigree and bulk method-derived breeding lines of five crosses with RGA-derived lines. The RGA method was found to be almost two times more efficient in capturing high-yielding lines with a high breeding value and thus accelerated genetic gain much more than the bulk and pedigree methods. The RGA method is not only more efficient but also significantly cheaper (~24%) compared to pedigree methods. The cost per kilogram of genetic gain in yield for the RGA lines is almost 3 times lower than the bulk method and 4.5 times lower than the pedigree method, and it can be achieved in half the time required for line development with either the bulk or pedigree method.
]]>Agronomy doi: 10.3390/agronomy14030565
Authors: Rongrong Tan Long Jiao Danjuan Huang Xun Chen Hongjuan Wang Yingxin Mao
Gray blight disease stands as one of the most destructive ailments affecting tea plants, causing significant damage and productivity losses. However, the dynamic roles of defense genes during the infection of gray blight disease remain largely unclear, particularly concerning their distinct responses in resistant and susceptible cultivars. In the pursuit of understanding the molecular interactions associated with gray blight disease in tea plants, a transcriptome analysis unveiled that 10,524, 17,863, and 15,178 genes exhibited differential expression in the resistant tea cultivar (Yingshuang), while 14,891, 14,733, and 12,184 genes showed differential expression in the susceptible tea cultivar (Longjing 43) at 8, 24, and 72 h post-inoculation (hpi), respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses highlighted that the most up-regulated genes were mainly involved in secondary metabolism, photosynthesis, oxidative phosphorylation, and ribosome pathways. Furthermore, plant hormone signal transduction and flavonoid biosynthesis were specifically expressed in resistant and susceptible tea cultivars, respectively. These findings provide a more comprehensive understanding of the molecular mechanisms underlying tea plant immunity against gray blight disease.
]]>Agronomy doi: 10.3390/agronomy14030564
Authors: Amalia Nafisah Rahmani Irawan Daisuke Komori
There is valuable information that can be obtained beyond using a fixed crop calendar with coarse spatial resolution. Knowing the dynamics of the timing and location in which a particular crop is planted and harvested, with an annual temporal resolution and a fine spatial resolution, is crucial not only for monitoring crop conditions and production but also for understanding crop management under changing climates. In this study, the Normalized Difference Vegetation Index (NDVI) was utilized to develop a historical crop calendar for paddy in Indonesia with a 1 km resolution from 2001 to 2021. The result of this study is the first dynamic crop calendar that includes information about the planting, peak, and harvesting dates, as crop growth indicators, derived from the analysis of NDVI value fluctuations. Additionally, this dataset also includes the total number of cropping seasons each year. In Indonesia, there are intensive agricultural activities, including two dry cropping seasons that occur after the wet cropping season. However, this dataset is limited only to crops grown during the dry seasons, which typically begin in February and June. This dataset offers significant information at a finer spatiotemporal resolution to enable studies on agricultural fields undergoing climate change, although it is more country–specific than the other established dataset. The annual crop calendar dataset from 2001 to 2021 underscores the significance of examining the variability in cropping seasons over the years. This exploration aims to deepen our comprehension of the interplay between cropping seasons, climatic indicators, and even the social factors influencing farmers’ decisions. Furthermore, presented at a 1 km resolution, this dynamic crop calendar underscores the need for a more precise representation of diverse cropping intensities and seasons, particularly within small and fragmented agricultural areas.
]]>Agronomy doi: 10.3390/agronomy14030563
Authors: Jinwei Wang Yousef Alhaj Hamoud Qinyuan Zhu Hiba Shaghaleh Jingnan Chen Fenglin Zhong Maomao Hou
Lettuce is a water-sensitive stem-used plant, and its rapid growth process causes significant disturbances to the soil. Few studies have focused on the gaseous carbon emissions from lettuce fields under different irrigation methods. Therefore, this study investigated the effect of different drip-irrigation lower limits and methods (drip and furrow irrigation) on greenhouse gas (CO2, CH4) emissions from lettuce fields. Thus, drip irrigation (DI) was implemented using three different lower limits of irrigation corresponding to 75%, 65%, and 55% of the field capacity, and named DR1, DR2, and DR3, respectively. Furrow irrigation (FI) was used as a control treatment. The CO2 and CH4 emission fluxes, soil temperature, and soil enzyme activities were detected. The results showed that the cumulative CO2 emission was highest under DR3 and relatively lower under DR1. For the FI treatment, the cumulative CO2 emission (382.7 g C m−2) was higher than that under DR1 but 20.2% lower than that under DR2. The cumulative CH4 emissions under FI (0.012 g C m−2) were the greatest in the whole lettuce growth period, while DR2 and DR3 treatments emitted lower amounts of CH4. The irrigation method considerably enhanced the activity of urease and catalase, meanwhile promoting CO2 emission. The low irrigation amount each time combined with high irrigation frequency reduced soil CO2 emission while increasing CH4 emission. From the perspective of the total reduction of gaseous carbon, DR1 is the optimal drip irrigation method among all the irrigation lower limits and methods.
]]>Agronomy doi: 10.3390/agronomy14030562
Authors: Milica Colovic Anna Maria Stellacci Nada Mzid Martina Di Venosa Mladen Todorovic Vito Cantore Rossella Albrizio
This study analyzed the capability of aerial RGB (red-green-blue) and hyperspectral-derived vegetation indices to assess the response of sweet maize (Zea mays var. saccharata L.) to different water and nitrogen inputs. A field experiment was carried out during 2020 by using both remote RGB images and ground hyperspectral sensor data. Physiological parameters (i.e., leaf area index, relative water content, leaf chlorophyll content index, and gas exchange parameters) were measured. Correlation and multivariate data analysis (principal component analysis and stepwise linear regression) were performed to assess the strength of the relationships between eco-physiological measured variables and both RGB indices and hyperspectral data. The results revealed that the red-edge indices including CIred-edge, NDRE and DD were the best predictors of the maize physiological traits. In addition, stepwise linear regression highlighted the importance of both WI and WI:NDVI for prediction of relative water content and crop temperature. Among the RGB indices, the green-area index showed a significant contribution in the prediction of leaf area index, stomatal conductance, leaf transpiration and relative water content. Moreover, the coefficients of correlation between studied crop variables and GGA, NDLuv and NDLab were higher than with the hyperspectral indices measured at the ground level. The findings confirmed the capacity of selected RGB and hyperspectral indices to evaluate the water and nitrogen status of sweet maize and provided opportunity to expand experimentation on other crops, diverse pedo-climatic conditions and management practices. Hence, the aerially collected RGB vegetation indices might represent a cost-effective solution for crop status assessment.
]]>Agronomy doi: 10.3390/agronomy14030561
Authors: Rubén Collantes Ramon Salcedo Enric Armengol Jose F. Schlosser Emilio Gil
Pesticide application equipment (PAE) is the last part of the chain during the plant protection process. The use-phase of plant protection products (PPP) has been addressed in two EU Directives: 128/2009/EC and 127/2009/EC. This last one covers all the mandatory technical requirements to be fulfilled by new sprayers prior to their placement in the market. The objective of this research was to develop a potential decision support system (DSS) to evaluate and quantify the degree of implementation of all the required characteristics of new sprayers, including not only the mandatory requirements but also specifications widely described in the corresponding harmonized standard ISO 16119. It includes 10 independent elements of the sprayer, including a list of technical specifications listed in the applied standards ISO 16119 and ISO 16122. The relative influence of every one of the different elements has been quantified based on previous research. The algorithm enables the establishment of an objective relative classification of the sprayers to differentiate among different machines, mainly based on their quantified environmental contamination risk. The DSS can also discriminate among sprayers that should not reach the market due to their non-compliance with any of the mandatory requirements.
]]>Agronomy doi: 10.3390/agronomy14030560
Authors: Bhimsen Shrestha Blair L. Stringam Murali K. Darapuneni Kevin A. Lombard Soumaila Sanogo Charles Higgins Koffi Djaman
Irrigation and nitrogen management are crucial for sustainable potato (Solanum tuberosum L.) production. A field experiment was conducted during the 2022 and 2023 growing seasons at Farmington, New Mexico, to evaluate the performance of two chip potato varieties (Lamoka and Waneta) under three irrigation regimes (full irrigation (FI), 20% deficit irrigation (DI) and 40% DI) and seven nitrogen fertilizer rates (0, 60, 115, 170, 220, 280, and 340 kg N/ha). The treatment combinations of irrigation regimes, nitrogen rates, and varieties were arranged in a split–split plot design with three replications as main plot, sub-plot, and sub-sub plot, respectively. The two-year results showed that irrigation regimes had the most significant effect on plant growth, physiology, and tuber yield of the potato varieties. For both Lamoka and Waneta, the plant height and canopy cover were lower under 40% DI than under 20% DI and FI treatments. The SPAD meter values were higher under 40% DI, followed by 20% DI and FI treatments, whereas the stomatal conductance was higher under FI, followed by 20% DI and 40% DI during both growing seasons. Regardless of nitrogen rates and variety, a 20% water-saving irrigation strategy reduced the total tuber yield by 4.5% and 22.1% in the 2022 and 2023 growing seasons, respectively, while the 40% water-saving irrigation strategy reduced total tuber yield by 36.8% and 58.2% in the 2022 and 2023 growing seasons, respectively, as compared to full irrigation. Shifting from full irrigation to 20% DI could save 711.2 to 1036.3 m3/ha of irrigation water. For Lamoka, the highest total tuber yield was obtained with 60 kg N/ha under 20% DI and 220 kg N/ha under FI in 2022 and 2023, respectively. For Waneta, the highest total tuber yield was obtained with 115 kg N/ha under 20% DI and 170 kg N/ha under FI in 2022 and 2023, respectively. Maximum water use efficiency (WUE) was obtained at 60 kg N/ha with 20% DI for both Lamoka and Waneta in 2022, while maximum WUE was obtained at 220 kg N/ha under FI for Lamoka and at 170 kg N/ha for Waneta in the 2023 season. The maximum nitrogen use efficiency (NUE) was achieved with 60 kg N/ha under 20% DI for both varieties during both growing seasons. Thus, for sustainable irrigation and nitrogen management, the application of a 20% deficit irrigation strategy with a lower nitrogen rate (60 to 170 kg N/ha) could be the best option to improve WUE and NUE with minimal tuber yield reduction. Our study suggested that 40% deficit irrigation would not be beneficial as compared to both full irrigation and 20% water-saving irrigation.
]]>Agronomy doi: 10.3390/agronomy14030559
Authors: Abdulaziz G. Alghamdi Akram K. Alshami Ahmed El-Shafei Abdulrasoul M. Alomran Arafat Alkhasha Anwar A. Aly Abdulaziz R. Alharbi
The tomato is a vital component of agriculture and is the second-most important vegetable globally. Maintaining a high tomato production requires both water quality and quantity. Water-scarce regions like Saudi Arabia still lack an understanding of the impact of deficit irrigation and the use of a blend of saline and freshwater, especially their nuanced impact across growth stages. The purpose of this study was to evaluate the effects of six different irrigation amounts: full irrigation with 100% ETc (FI), regulated deficit irrigation with 60% ETc (DI), and deficit irrigation with 60% ETc, except for the initial (DI-int), development (DI-dev), mid-season (DI-mid), and late-season (DI-lat) stages. This was performed with three different water qualities: fresh (FW), saline (SW), and fresh-saline blend (1:1) (MW) water. FW and MW enhanced the growth, physiology, morphology, yield, and quality, while SW had the lowest values. DI reduced these parameters and lowered yields by 13.7%, significantly improving water use efficiency (WUE) by 44% and fruit quality. DI-mid or DI-lat slightly improved yields while remarkably decreasing WUE and fruit quality. DI outperforms deficit irrigation in all growth stages except one, and countries with limited freshwater resources can benefit from a mix of fresh and saline water with a 60% ETc deficit irrigation, resulting in greater water savings.
]]>Agronomy doi: 10.3390/agronomy14030558
Authors: Jimmy A. Ocaña-Reyes Marco Gutiérrez Richard Paredes-Espinosa Christian A. Riveros Gloria P. Cárdenas Nino Bravo Astrid Quispe-Tomas Luiz P. Amaringo-Cordova Juan C. Ocaña-Canales José W. Zavala-Solórzano Hugo A. Huamaní Yupanqui Juancarlos Cruz Richard Solórzano-Acosta
Tillage conservation practices (CA), traditional agriculture (TA), and liming influence soil properties and crop yield. However, it is essential to demonstrate which tillage and liming practices improve soil properties and forage corn yield. This study compared soil properties and forage corn production in two tillage systems with the addition of dolomite and lime, which formed four treatments. The tillage in the first three days surpassed the TA soil CO2 emission, with 64.8% more CO2 than in the CA soil, and the TA hydraulic conductivity and bulk density were more suitable than those in the CA soil. The CA soil had 233 earthworms m−2 more than in TA. The TA green forage corn yielded 6.45 t ha−1 more than in CA, with a higher P, Ca, and Mg foliar content than in CA, but in the CA, the foliar N and K were higher than in TA. The liming increased soil cations (except K), highlighting the lime on dolomite with—52% Al and + 4.85 t ha−1 of forage corn compared to the control. Soil CO2 emission was far lower in CA than in TA, with a slightly lower forage yield, and other soil properties were improved, meaning lower land preparation costs and time savings than in TA. Lime improved acidic soil faster than dolomite, generating higher forage yields.
]]>Agronomy doi: 10.3390/agronomy14030557
Authors: Angel James Medina Medina Rolando Salas López Jhon Antony Zabaleta Santisteban Katerin Meliza Tuesta Trauco Efrain Yury Turpo Cayo Nixon Huaman Haro Manuel Oliva Cruz Darwin Gómez Fernández
One of the world’s major agricultural crops is rice (Oryza sativa), a staple food for more than half of the global population. In this research, synthetic aperture radar (SAR) and optical images are used to analyze the monthly dynamics of this crop in the lower Utcubamba river basin, Peru. In addition, this study addresses the need to obtain accurate and timely information on the areas under cultivation in order to calculate their agricultural production. To achieve this, SAR sensor and Sentinel-2 optical remote sensing images were integrated using computer technology, and the monthly dynamics of the rice crops were analyzed through mapping and geometric calculation of the surveyed areas. An algorithm was developed on the Google Earth Engine (GEE) virtual platform for the classification of the Sentinel-1 and Sentinel-2 images and a combination of both, the result of which was improved in ArcGIS Pro software version 3.0.1 using a spatial filter to reduce the “salt and pepper” effect. A total of 168 SAR images and 96 optical images were obtained, corrected, and classified using machine learning algorithms, achieving a monthly average accuracy of 96.4% and 0.951 with respect to the overall accuracy (OA) and Kappa Index (KI), respectively, in the year 2019. For the year 2020, the monthly averages were 94.4% for the OA and 0.922 for the KI. Thus, optical and SAR data offer excellent integration to address the information gaps between them, are of great importance to obtaining more robust products, and can be applied to improving agricultural production planning and management.
]]>Agronomy doi: 10.3390/agronomy14030556
Authors: Ionuț Ovidiu Jerca Sorin Mihai Cîmpeanu Răzvan Ionuț Teodorescu Elena Maria Drăghici Oana Alina Nițu Sigurd Sannan Adnan Arshad
Understanding how cherry tomatoes respond to variations in greenhouse microclimate is crucial for optimizing tomato production in a controlled environment. The present study delves into the intricate relationship between summer-grown cherry tomatoes (Cheramy F1) and greenhouse conditions, exploring the influence of these conditions on growth attributes, inflorescence development, and yield potential. The aim of the study was to characterize the chronology of reproductive events, specifically flowering and fruit stages, in correlation with the prevailing greenhouse climate during the development of the first ten inflorescences on the plant. The performance of each inflorescence has been ranked based on available data, which involve a comparative analysis of both the time duration (number of days) and the frequency of yield-contributing traits, specifically the total number of flowers at the anthesis stage. The duration of each stage required for completion was recorded and presented as a productivity rate factor. Greenhouse conditions exhibited variations during the vegetative and reproductive stages, respectively, as follows: temperature - 25.1 °C and 21.33 °C, CO2 levels - 484.85 ppm and 458.85 ppm, light intensity - 367.94 W/m2 and 349.52 W/m2, and humidity - 73.23% and 89.73%. The collected data conclusively demonstrated a substantial impact of greenhouse microclimate on plant growth, productivity, and inflorescence development. The development of flowers and fruit has been categorized into five stages: the fruit bud stage (FB), the anthesis stage (AS), the fruit setting stage (FS), the fruit maturation stage (FM), and the fruit ripening stage (FR). An irregular productivity and development response was noted across the first (close to roots) to the tenth inflorescence. Inflorescence 5 demonstrated the highest overall performance, followed by inflorescence numbers 4 and 6. The study findings provide valuable insights for enhancing greenhouse operations, emphasizing the improvement of both the yield and growth of cherry tomatoes while promoting environmental sustainability. A statistical analysis of variance was used to rigorously examine the presented results, conducted at a confidence level of p < 0.05.
]]>Agronomy doi: 10.3390/agronomy14030555
Authors: Guihua Lv Xiangnan Li Tingzhen Wang Zhenxing Wu Ruiqiu Fang Jianjian Chen
Mesotrione is a widely used post-emergence herbicide for maize. The toxicity of mesotrione to maize (especially sweet corn) has been widely reported, and some sweet corn varieties are highly sensitive to mesotrione, which affects subsequent plant growth periods. However, the molecular mechanisms responsible for the differences in susceptibility to mesotrione are not known. By comparing changes in the transcriptome of mesotrione-tolerant line 301 and mesotrione-sensitive line 276 after mesotrione treatment, we found that the genes coding light-harvesting chlorophyll protein complex were induced in 301, and the genes coding loosening cell walls were overrepresented in 276. The net photosynthetic rate, maximum photochemical efficiency of leaf PSII, photochemical quenching of chlorophyll fluorescence, and the electron transport rate were significantly higher in 301 than in 276 after mesotrione treatment, and these effects became more severe as time passed. In addition, oxidative balance was also affected by mesotrione. Compared with 301, SOD, POD, and CAT activities were significantly reduced with longer exposure time in 276. The results suggested that sweet corn can mitigate herbicide mesotrione toxicity by improving photosynthesis, ROS scavenging, and cell wall synthesis.
]]>Agronomy doi: 10.3390/agronomy14030554
Authors: María Dolores Granado-Castro María Dolores Galindo-Riaño Jesús Gestoso-Rojas Lorena Sánchez-Ponce María José Casanueva-Marenco Margarita Díaz-de-Alba
A new biosorbent obtained from Calabrese broccoli stalks has been prepared, characterised and used as an effective, low-cost and ecofriendly biomass to remove Pb(II) from aqueous solutions, without any complicated pretreatment. Structural and morphological characterisation were performed by TGA/DGT, FTIR and SEM/EDX; the main components are hemicellulose, starches, pectin, cellulose, lignin and phytochemicals, with important electron donor elements (such as S from glucosinolates of broccoli) involved in Pb(II) sorption. The biosorbent showed values of 0.52 and 0.65 g mL−1 for bulk and apparent densities, 20.6% porosity, a specific surface area of 15.3 m2 g−1, pHpzc 6.25, iodine capacity of 619 mg g−1 and a cation exchange capacity of 30.7 cmol kg−1. Very good sorption (88.3 ± 0.8%) occurred at pH 4.8 with a biomass dose of 10 g L−1 after 8 h. The Freundlich and Dubinin–Radushkevich isotherms and the pseudo-second-order kinetic models explained with good fits the favourable Pb(II) sorption on the heterogeneous surface of broccoli biomass. The maximum adsorption capacity was 586.7 mg g−1. The thermodynamic parameters evaluated showed the endothermic and spontaneous nature of the Pb(II) biosorption. The chemical mechanisms mainly involved complexation, ligand exchange and cation–π interaction, with possible precipitation.
]]>Agronomy doi: 10.3390/agronomy14030553
Authors: Hongyan Zhu Bingyan Zheng Weizheng Zhong Jinbo Xu Weibo Nie Yan Sun Zilong Guan
Salt and nutrient transport and transformations during water infiltration directly influence saline soil improvement and the efficient use of water and fertilizer resources. The effects of soil initial salinity (18.3 g/kg, 25.5 g/kg, 42.2 g/kg, 79.94 g/kg, and 165 g/kg, respectively, labeled S1 to S5) on the infiltration and leaching characteristics of water, salt, and nitrogen were analyzed via a one-dimensional vertical fertilizer infiltration experiment. Meanwhile, the estimation models of cumulative infiltration and wetting front, including the effect of soil initial salinity, were established. The results showed that, with the increase in soil initial salinity, the cumulative infiltration within the same time decreased, and the migration time of wet front to 45 cm was longer. The time required for S5 to reach the preset cumulative infiltration was more than six times that of S1, and, for the wet front migration to 45 cm, the time requirement for S5 was about four times that of S1. In the established Kostiakov model and wetting front model, the coefficients all decreased with the increase in soil initial salinity, and the test index R2 values both reached 0.999. In the Kostiakov model, coefficient K had a linear relationship with the natural logarithm of initial soil salt content, while index a had a direct linear relationship with initial soil salt content. The cumulative leachate volume decreased with the increase in soil initial salinity, and the corresponding data of S3 and S5 were reduced by 37% and 57.3%, respectively, compared with S1. The electrical conductivity values of S1, S3, and S5 were 15.4, 209.8, and 205.6 ms/cm, respectively, being affected by the initial content in soil, soil moisture transport rate, and exogenous potassium nitrate (KNO3) addition. The NO3−-N concentrations in the leachates of S1, S3, and S5 at the end of leaching were 55.26, 16.17, and 3.2 mg/L, respectively. Based on the results of this study, for soil with high initial salinity, the conventional irrigation amount (2250 m3/ha) of the general soil in the study area could not meet the requirements of leaching salt. These results can provide a reference for the formulation of irrigation and fertilization strategies for soils with different salinity and contribute to the sustainable development of saline soil agriculture and the ecological environment.
]]>Agronomy doi: 10.3390/agronomy14030552
Authors: Xin Zhao Zeyi Zhao Fengnian Zhao Jiangfan Liu Zhaoyang Li Xingpeng Wang Yang Gao
Accurate nitrogen fertilizer management determines the yield and quality of fruit trees, but there is a lack of multispectral UAV-based nitrogen fertilizer monitoring technology for orchards. Therefore, in this study, a field experiment was conducted by UAV to acquire multispectral images of an apple orchard with dwarf stocks and dense planting in southern Xinjiang and to estimate the nitrogen content of canopy leaves of apple trees by using three machine learning methods. The three inversion methods were partial least squares regression (PLSR), ridge regression (RR), and random forest regression (RFR). The results showed that the RF model could significantly improve the accuracy of estimating the leaf nitrogen content of the apple tree canopy, and the validation set of the four periods of apple trees ranged from 0.670 to 0.797 for R2, 0.838 mg L−1 to 4.403 mg L−1 for RMSE, and 1.74 to 2.222 for RPD, among which the RF model of the pre-fruit expansion stage of the 2023 season had the highest accuracy. This paper shows that the apple tree leaf nitrogen content estimation model based on multispectral UAV images constructed by using the RF machine learning method can timely and accurately diagnose the growth condition of apple trees, provide technical support for precise nitrogen fertilizer management in orchards, and provide a certain scientific basis for tree crop growth.
]]>Agronomy doi: 10.3390/agronomy14030551
Authors: Shaodong Wang Yifan Li Qian Li Xucan Ku Guoping Pan Qiyun Xu Yao Wang Yifei Liu Shuaiwen Zeng Shah Fahad Hongyan Liu Jiaolong Li
Organic fertilizer is utilized to improve the organic carbon levels in arable soils, which is helpful for soil quality improvement and crop yield increase. However, the after-effect of organic fertilizer varies among regions with different temperature and precipitation conditions, and the extent of the impact remains unknown. This study aimed to investigate the impact of varying temperature and rainfall conditions on the accumulation of soil organic carbon after organic fertilizer application. A meta-analysis of 168 peer-reviewed studies published between 2005 and 2022 involving a total of 464 trials was conducted. The following was discovered: (1) In the major grain-producing areas of China, there was a significant positive correlation (p < 0.01) between latitude and soil organic carbon content. Meanwhile, temperature and precipitation had a significant negative correlation (p < 0.01) with soil organic carbon content. (2) The increase in temperature inhibited the increase in soil organic carbon storage. The improvement effect of organic fertilizer application in the low-temperature areas was significantly increased by 60.93% compared with the mid-temperature areas, and by 69.85% compared with the high-temperature areas. The average annual precipitation affected the after-effect of organic fertilizer as follows: 400–800 mm > 400 mm > more than 800 mm. (3) The influence of climatic conditions on the after-effect of organic fertilizer was more significant depending on the specific tillage practice. To increase organic fertilizer use efficiency and eliminate greenhouse gas emissions, liquid organic fertilizers with abundant trace nutrients and amino acids, which take advantage of releasing nutrients more swiftly and have a better fertilization effect, could be an alternative to traditional organic fertilizers.
]]>Agronomy doi: 10.3390/agronomy14030550
Authors: Salvatore Ceccarelli Stefania Grando
This review paper addresses the importance of increasing agrobiodiversity to cope with climate change and, at the same time, providing a sufficient amount of healthy food. This is in agreement with the messages from ecology and medicine indicating the advantages of biodiversity in general and agrobiodiversity in particular for the planet and for our health. Plant breeding is considered to be one of the causes of the decline in agrobiodiversity, and therefore, this paper illustrates alternatives to the commonly used approach based on centralized selection. The first alternative is decentralized participatory breeding, which adapts crops to both different agronomic environments and client preferences, representing an “option by context” model of research. The second alternative is evolutionary breeding, which is a more dynamic strategy than participatory plant breeding because it merges the advantages of decentralization with the ability of dynamic mixtures and evolutionary populations to cope with biotic and abiotic stresses and evolve, thus adapting to climate change and to the associated changes in the spectrum of pests. A crop capable of evolving as the environment around it evolves appears to be the most ideal way of responding to climate change and increasing agricultural biodiversity.
]]>Agronomy doi: 10.3390/agronomy14030549
Authors: Katarzyna Gościnna Katarzyna Retmańska Elżbieta Wszelaczyńska Jarosław Pobereżny
The aim of this study was to determine the effect of the application of different organic matter, UGmax soil conditioner and simplifications in potato cultivation on the content of dry matter, starch and sugars in tubers of the medium-early edible cultivar ‘Satina’ after harvest and after long-term storage. The highest dry matter (173.4 g kg−1) and starch (124.6 g kg−1 f. m.) content was obtained with the simultaneous application of a manure with soil conditioner at 100% mineral fertilization. In the case of sugars, the withdrawal of the soil conditioner from the crop proved most beneficial, for total sugars on the stubble intercrop (5.06 g kg−1 f. m.) and for reducing sugars (1.99 g kg−1 f. m.) in the case of straw treatment. Each protection reduction applied resulted in a significant reduction in starch content. In this regard, the withdrawal of herbicides with the simultaneous application of manure and UGmax proved most beneficial. Long-term storage of tubers caused a significant reduction in their quality in terms of dry matter and starch content (average by −3.6 and −2.3%, respectively) and an increase in total and reducing sugars (average by 11.8 and 9.6%, respectively). The decrease in dry matter and starch content was significantly influenced by the 50% reduction in NPK fertilization applied during the growing season, while the application of soil conditioner with full protection contributed to the increase in reducing sugars after storage at 28.9 pts%. Our research is in line with current trends of used potato cultivation technologies focused mainly on environmental protection, so the results of this study can provide a basis for validation for researchers currently engaged in such evaluation.
]]>Agronomy doi: 10.3390/agronomy14030548
Authors: Imran Ali Lakhiar Haofang Yan Jianyun Zhang Guoqing Wang Shuaishuai Deng Rongxuan Bao Chuan Zhang Tabinda Naz Syed Biyu Wang Rui Zhou Xuanxuan Wang
Plastic products in plant production and protection help farmers increase crop production, enhance food quality, and reduce global water use and their environmental footprint. Simultaneously, plastic has emerged as a critical ecological issue in recent years, and its pollution has significantly impacted soil, water, and plants. Thus, this review examines the multifaceted problems of plastic pollution in agriculture as a risk to food security, the ecosystem, and the environment. The study’s objective was to review and present the most recent information on using different plastic products in agriculture, the sources of plastic pollution, the advantages and drawbacks of using plastic products, and the strategies for mitigating plastic pollution in agriculture. Furthermore, after examining current plastic applications, benefits, adverse effects, and risks to soil, plants, and the environment, we addressed the requirements for technological advancements, regulations, and social processes that could contribute to mitigating plastic pollution in our ecosystems. We identified different pathways toward more sustainable use of plastics in agriculture and discussed future research directions.
]]>Agronomy doi: 10.3390/agronomy14030547
Authors: Huajie Guo Zhiying Qin Wei Ren Hongmei Feng Wenliang Chen Longlong Liu Zhaoxia Sun
As a nutrient-rich multigrain crop, buckwheat is a typical “medicinal food homology” crop that is rich in flavonoids, including rutin and various vitamins. It has positive anti-oxidant and anti-tumour properties and lowers blood pressure. However, due to strict self-crossing characteristics, slow progress has been made in Tartary buckwheat (TB) cross-breeding, resulting in the slow breeding of new varieties of new TB varieties, which has limited the improvement of yield and quality. Therefore, mutant breeding is a rapid and effective technique for broadening and innovating TB breeding. In recent years, improving qualities related to yield, lodging resistance, and stability have become key points in TB breeding. Based on the above findings, excellent, potentially valuable TB lines with rich phenotypes were obtained for the TB mutation library via ethyl methanesulfonate (EMS), laying a foundation for creating new TB germplasms. In this study, we systematically investigated more than 10 agronomic traits of JQ2 and JQ4 mutants, including plant type, leaf colour, grain type, grain colour, grain number per plant, grain length, grain width, grain weight per plant, and 1000-grain weight. The results show that the maximum number of grains per plant was 1956, the weight was 32.84 g, and the 1000-grain weight was 30.89 g. The maximum number of grains per JQ4 plant was 2308, and the weight was 44.82 g. The maximum 1000-grain weight was 24.7 g. Among the 295 JQ2 mutants and 153 JQ4 mutants, 10 flavonoids (orientin, morin, quercetin, kaempferol, luteolin, naringin, hesperetin, myricetin, hesperidin, and rutin) were detected with near infrared spectroscopy (NIR). The mutants were divided into five groups according to the flavonoid content of the JQ2 mutants, of which the first group included 31 individual lines. and the second to fifth groups included 70, 69, 72, and 53 lines, respectively. The JQ4 mutants were divided into four classes, of which 41, 50, 32, and 30 were individual lines, respectively, with the highest rutin content being 82.06 mg/g. In summary, through systematic analysis and screening of the agronomic traits and flavonoid contents of JQ2 and JQ4 mutant seeds, we obtained three lines with a high 1000-grain weight, including two JQ2 mutant lines (30.89 g) and one JQ4 mutant line, which reached 24.70 g and ten lines with high grain weight per plant. This included 8 JQ2 mutants and 2 JQ4 mutants, as well as 72 high-rutin mutants (including 31 lines from JQ2 and 41 lines from JQ4 mutants). These elite lines provide the material basis for creating TB germplasms with excellent qualities and cultivation characteristics.
]]>Agronomy doi: 10.3390/agronomy14030546
Authors: Lu Wang Cunjie Yan Wenqi Zhang Yinghu Zhang
Exploring the crop production water footprint and their driving factors is of significant importance for management of agricultural water resources. However, how do we effectively assess the total agricultural water consumption and explore the significance of their driving factors, i.e., population, economy, and agricultural production conditions, using a backpropagation neural network (BPNN)? It is still ambiguous. Water consumption for crops during the growing season is explicitly explored by way of water footprint indicators (green water footprint, WFPg, and blue water footprint, WFPb). This study provides new insights into the factors driving the changes in crop production water footprint in Taiyuan City over the period of 2005–2021. Simulations of crop evapotranspiration using the CROPWAT model were quantified. The results showed that Taiyuan City has a low crop yield level below the average level of China, with the highest crop yield in maize. The crop production water footprint in Taiyuan City showed a non-linearly decreasing trend over time. The average annual crop production water footprint was 187.09 × 103 m3/kg in Taiyuan City, with the blue water footprint and green water footprint accounting for 63.32% and 36.68%, respectively. The crop production water footprint in the west and north of Taiyuan City was significantly higher than those in other areas, accounting for 42.92% of the total crop production water footprint. Oilseed crops contributed most to the total crop production water footprint, accounting for 47.11%. The GDP and total sown area of crops were more important for the changes in WFPb. Agricultural machinery power and agriculture-to-non-agriculture ratio were more important for the changes in WFPg. Agricultural machinery power and GDP were more important for the changes in IWFP. In-depth analysis of the factors driving the changes in crop production water footprint is dramatically important for agricultural decision makers to mitigate water resource pressure in Taiyuan City.
]]>Agronomy doi: 10.3390/agronomy14030545
Authors: Christopher Lee Augustin David W. Franzen
Soybean (Glycine max L.) is a new cash crop grown in north central and northwestern North Dakota (ND). Soils and climate in these new soybean areas differ from current fertilizer guidelines. A three-year study to evaluate soybean fertility best management practices was initiated in the spring of 2016 and concluded in 2018. Each year had two sites and twelve treatments. One site was acidic (pH < 6.2) and the other was alkaline (pH > 7.2). Both site treatments were: untreated check, inoculated with rhizobia (Bradyrhizobium japonicum L.), broadcast urea (55 kg ha−1), broadcast MAP (110 kg ha−1), In-furrow 10-34-0 (28 L ha−1), in-furrow 6-24-6 (28 L ha−1), foliar 3-18-18 (28 L ha−1) at V5 and R2, and foliar 3-18-18 (28 L ha−1) with sulfate (1.1 kg ha−1) at V5 and R2. The acidic site had two treatments of sugar beet (Beta vulgaris L.) waste lime (4411 kg ha−1 and 8821 kg ha−1). The alkaline site received treatments of iron ortho-ortho-EDDHA (7.1 L ha−1), and naked ortho-ortho-EDDHA (7.1 L ha−1). An in-furrow treatment of cobalt (2.9 kg cobalt-sulfate ha−1) was added in 2018. Fertilizer treatments did not impact soybean yield, protein content and oil content at the 0.05 significance level.
]]>Agronomy doi: 10.3390/agronomy14030544
Authors: Zhengdi Han Huijing Hou Xianzi Yao Xiang Qian Mingyao Zhou
Conventional water and fertilizer management practices have led to elevated greenhouse gas emissions from rice fields and decreased the efficiency of water and fertilizer utilization in agricultural land. The implementation of water-saving irrigation and the substitution of chemical fertilizers with organic alternatives can influence CH4 and N2O emissions in rice fields. However, it remains unclear how the simultaneous application of both methods will affect the CH4 and N2O emissions in rice fields. Therefore, two irrigation methods (F: flooded irrigation; C: controlled irrigation) and three fertilization modes (A: full chemical fertilizer; B: bio-organic fertilizer replacing 15% chemical nitrogen fertilizer; C: bio-organic fertilizer replacing 30% chemical nitrogen fertilizer) were set up through field experiments to explore the effect of greenhouse gas emission reduction in rice fields by combining controlled irrigation and bio-organic fertilizers. Substituting some chemical fertilizers with bio-organic fertilizers can lower the peak CH4 and N2O fluxes in rice fields, leading to a decrease in the cumulative CH4 and N2O emissions by 11.9~29.7% and 10.8~57.3%, respectively. The reductions led to a considerable decrease in the global warming potential (GWP) and the greenhouse gas emission intensity (GHGI) by 16.1~48.1% and 16.3~48.1%, respectively. Controlled irrigation significantly reduced CH4 emissions by 55.2~69.4% compared with flooded irrigation in rice fields. However, it also increased N2O emissions by 47.5~207.9%, considerably reducing their GWPs by 11.8~45.5%. Neither bio-organic fertilizer substitution nor controlled irrigation significantly affected rice yield. Replacing 15% of chemical nitrogen fertilizers with bio-organic fertilizers in controlled irrigation rice fields can minimize rice GWP and GHGI. The study’s results are of significant importance for enhancing the regulation of greenhouse gases in farmland and achieving sustainable agriculture through cleaner production.
]]>Agronomy doi: 10.3390/agronomy14030543
Authors: Fan Zhang Junming Zhang Qifeng Li Yang Yang Yunyan Sheng
Soil salinization is one of the main problems faced by modern agricultural production, especially cucumber production. This study screened the salt–alkali-tolerant cultivar ‘D1909’ and the salt–alkali-sensitive cultivar ‘D1604’ from 32 different cucumber ecological types on the basis of morphological indicators and salt–alkali indices combined with relevant physiological and biochemical indices. By performing a transcriptome metabolome analysis, the key gene CsSRG1, which is responsive to salt–alkali stress in cucumber, was screened, and its function was verified. The role of CsSRG1 in reducing salt–alkali stress in cucumber was clarified, and the mechanism of salt–alkali tolerance in cucumber was preliminarily explored. This study provides germplasm resources for cucumber salt–alkali tolerance breeding and a theoretical basis for the effective use of saline alkali soil to achieve high quality and high yield in other crops.
]]>Agronomy doi: 10.3390/agronomy14030542
Authors: Bin Li Li Zhang Lincao Wei Yujie Yang Zhexuan Wang Bo Qiao Lingjuan Han
(1) Background: Low-calcium stress can have adverse effects on the rhizosphere environment of cucumber, subsequently impacting cucumber growth. However, plant-growth-promoting rhizobacteria can directly or indirectly enhance plant growth and induce plant tolerance, thereby mitigating the detrimental effects of low-calcium stress on cucumber growth. This study aims to elucidate the role of Bacillus amyloliquefaciens QST713 in the rhizosphere environment of cucumber under low-calcium stress, providing a theoretical basis for the application and promotion of Bacillus amyloliquefaciens. (2) Methods: This study used the ‘JinYou NO.4′ cucumber variety as test material, setting four treatments of CK, CK+Q, LCa, LCa+Q. We conducted measurements of plant height and stem diameter for four groups of cucumber plants: before treatment (0 d), and at 10 d, 20 d, 30 d, and 60 d after treatment. Additionally, we determined the biomass of cucumber plants under different treatments during the peak fruiting period. Inter-root matrix samples of cucumber were collected during the fruiting late period, and the physical and chemical properties and nutrient contents of the inter-root matrix of cucumber were determined, and bacterial microbial diversity and bacterial microbial communities were analysed using Illumina-MiSeq high-throughput sequencing technology. (3) Results: Low-calcium stress significantly inhibits the growth of cucumber plants. However, the application of Bacillus amyloliquefaciens QST713 effectively mitigates the inhibitory effects of low-calcium stress on cucumber growth. The application of Bacillus amyloliquefaciens QST713 was able to improve the physicochemical environment of the matrix and enhanced the absorption and utilisation of matrix nutrients in cucumber. The high-throughput sequencing analysis showed that the richness and diversity of bacterial communities and the number of bacteria decreased significantly under low-calcium stress, and increased significantly after the application of Bacillus amyloliquefaciens QST713. The composition of the dominant bacterial groups of the inter-root matrix of cucumber was basically the same among the four treatments, and the main difference was in the abundance of bacteria. The application of Bacillus amyloliquefaciens QST713 increased the relative abundance of bacteria that decreased under low-calcium stress, and decreased the relative abundance of bacteria that increased under low-calcium stress. (4) Conclusions: The results of this study elucidated the positive effects of Bacillus amyloliquefaciens QST713 on the growth and inter-root environment of cucumber under low-calcium stress, and provided a theoretical basis for in-depth research on the resistance of Bacillus amyloliquefaciens and its popularised application.
]]>Agronomy doi: 10.3390/agronomy14030541
Authors: Gianluigi Farru Fabiano Bisinella Scheufele Daniela Moloeznik Paniagua Fritz Keller Changyoon Jeong Daniele Basso
This study assesses the status of hydrothermal carbonization (HTC) technology and identifies barriers hindering its commercial viability. Conducting a global survey among HTC companies (with a total of 24 surveys sent), the research evaluates the current landscape, challenges, and future prospects of large-scale HTC operations. Furthermore, it presents a detailed global inventory of existing HTC facilities, illustrating geographical distribution and trends in application. Most of the companies are located in Europe, followed by Asia and North America. With substantial participation from HTC companies, exceeding 62% in the survey (15 companies), the study provides a comprehensive overview of diverse companies, their business models, regulatory challenges, and the overall state of HTC technology. The majority of companies in this study, approximately 80%, offer services in the field of waste management. This paper also explores the potential of HTC in transforming waste management practices, carbon sequestration methodologies, and the development of new materials. Employing a thorough SWOT analysis, the paper advocates for a broader adoption of HTC, emphasizing its transformative capacity in fostering sustainable management of urban, industrial, and agricultural residues, promoting circular economy principles, mitigating climate change, and offering a robust foundation for informed decision-making and sustainable development strategies.
]]>Agronomy doi: 10.3390/agronomy14030540
Authors: Qi Chen Yingying Zhou Yue Qi Wen Zeng Zhaoji Shi Xing Liu Jiaen Zhang
Recent studies have indicated that the invasive apple snail (Pomacea canaliculata) exhibits tolerance to the salinity levels present in coastal agricultural soils, suggesting that apple snails could potentially invade salt-affected coastal agricultural areas. However, the effects of the alien snail Pomacea canaliculata invasion on coastal saline soils, such as in terms of soil properties, microbial diversity, and abundance, remain poorly understood. To fill this gap, we conducted experiments involving three salinity levels (0, 2‰, and 5‰, w/w), coupled with varying snail densities (0, 5, and 10 snails per box), applied to agricultural soil. We analyzed soil chemical properties, enzyme activities, and bacterial communities. The findings revealed that heightened soil salinity increased soil electrical conductivity (EC) (exceeding 1312.67 μS cm−1). Under saline conditions, snail treatments significantly increased the soil organic matter (SOM) content from 15.82 mg kg−1 to 18.69 mg kg−1, and concurrently diminished the dissolved organic carbon (DOC) from 47.45 mg kg−1 to 34.60 mg kg−1. Both snail and salinity treatments resulted in ammonia nitrogen (NH4+-N) accumulation, while nitrate nitrogen (NO3−-N) concentrations remained low in salt-affected soils. A notable positive correlation existed between the EC and the activities of hydroxylamine reductase (HR) and peroxidase (POD), where HR exhibited a positive correlation with NH4+-N, and POD displayed a negative correlation with NO3−-N. Salinity substantially decreased the diversity and altered the composition of soil bacterial community, with the phyla Bacteroidota, Proteobacteria, and Firmicutes adapting to salt-affected soil environment and proliferating. Structural equation modeling (SEM) analysis indicated that snails exerted a direct influence on soil-available nitrogen (including NO3−-N and NH4+-N), while salinity impacted available nitrogen by modulating soil enzyme activities and bacterial communities. Our findings provide insights into how soil responds to the concurrent impacts of snail invasion and soil salinization, establishing some references for future research.
]]>Agronomy doi: 10.3390/agronomy14030539
Authors: Yuxin Chang Bowen Zhang Guolong Li Peng Zhang Huiyu Liu Shaoying Zhang
Northern China faces water scarcity, restricting water usage in place across Inner Mongolia’s western region. The integrated irrigation and fertilization model for sugar beet is undergoing rapid development and application in production. However, there is a concerning trend in production where the frequency of irrigation and fertilization is being increased blindly, resulting in the wastage of valuable water and fertilizer resources. Limiting water and fertilizer usage is an effective approach to improve sugar beet production efficiency. Sugar beets are a significant sugar crop in China. A split-plot design was employed to examine the impact of reducing water and fertilizer use on sucrose metabolism in sugar beet root. Our study was performed at the Ulanqab Institute of Agricultural and Forestry Sciences in Inner Mongolia from 2022 to 2023. Three levels of fertilization and irrigation were utilized. We investigated the interactions between irrigation and fertilization on sucrose accumulation in sugar beet root. We examined key enzyme activities involved in sucrose metabolism alongside their gene expression levels. The findings suggested that reducing irrigation by 15%, fertilization by 10%, or both irrigation by 15% and fertilization by 10%, increased sucrose concentrations of sugar beets compared to the control group administered conventional water and fertilizer. Over the two-year period, the average sucrose concentration increased by 0.45, 0.57, and 0.65 degrees, respectively, under each treatment. Subsequent research verified that appropriately reducing water and fertilizer can regulate the expression of enzyme genes, thus influencing enzyme activity. Moreover, due to the higher efficiency of enzyme synthesis compared to decomposition, it contributed to an increase in net enzyme activity. These findings suggest that an appropriate reduction of water and fertilizer can improve sucrose synthesis rates and increase the sucrose concentration in sugar beets, providing a theoretical basis for environmentally friendly generation and enhanced efficiency in sugar beet growth.
]]>Agronomy doi: 10.3390/agronomy14030538
Authors: Xichao Fan Jingtao Qin Mouchao Lv Mingliang Jiang
Irrigation districts are a pivotal infrastructure of agricultural water conservancy engineering. Implementing modernization will be the main task of large-scale irrigation districts for a considerable amount of time in the future. In this study, four typical large-scale irrigation districts in North China were investigated: the Renmin Shengliqu, Weishan, Shijin, and Zuncun irrigation districts. The concept of a modern irrigation district was deconstructed to establish an evaluation index system which includes four second-level indicators, twelve third-level indicators, and thirty fourth-level indicators. A hybrid approach based on AHP and OWA was used to quantify indicator weights used in group decision making. TOPSIS was introduced to measure the modernization level of the four irrigation districts. An obstacle factor diagnosis model was applied to search for key obstacle factors that will affect the modernization and improvement of the irrigation districts. The results showed that (1) the modernization levels of the Renmin Shengliqu, Weishan, Shijin, and Zuncun irrigation districts in 2020 and 2025 were 0.3916 and 0.5755, 0.3748 and 0.5396, 0.4493 and 0.6012, and 0.2343 and 0.6166, respectively. The evaluation results indicate that the four irrigation districts are still in the beginning phase (or even preparation phase) of the modernization process. (2) Eight indicators were identified as the main common obstacle factors for the four evaluated irrigation districts, including the irrigation water-use efficiency factor, the coverage proportion of information technology, the proportion of efficient water conservation irrigation areas, and so on. (3) There are two effective methods to enhance the modernization level of the four irrigation districts: improving water resource utilization efficiency and strengthening the management system with an emphasis on informatization. The present study can enrich the theoretical evaluation of irrigation districts and provide a scientific basis for the modernized construction and management of irrigation districts in China.
]]>Agronomy doi: 10.3390/agronomy14030537
Authors: Natalia Torres-Pagán Marta Muñoz Sara Barbero Roberta Mamone Rosa Peiró Alessandra Carrubba Adela M. Sánchez-Moreiras Diego Gómez de Barreda Mercedes Verdeguer
In recent years, interest in natural products with herbicidal activity as new tools for integrated weed management has increased. The European Union is demanding a reduction in the number of herbicides used, forbidding use of the most toxic ones, despite the problem of weed resistance increasing. Pelargonic acid (PA) is the only natural herbicide available in Spain. In this work, two field assays were performed with the natural compounds carvacrol (CAR), citral (CIT), eugenol (EUG), thymol (THY), p-cymene (P-CYM), (PA), and the combination of PA with CIT—all except P-CYM formulated by Seipasa—to test their herbicidal efficacy in real conditions. They were compared with commercial PA, glyphosate (GLY) and oxyfluorfen (OXY). In both experiments, GLY achieved the best weed control. Considering the natural herbicides, PA formulated by Seipasa and PA plus CIT were the most effective. From both experiments, some conclusions can be extracted for better herbicidal performance of natural products: (1) use products on sensitive weed species, (2) treat weeds at earlier phenological stages, (3) find the active doses in field conditions, (4) cover weeds well when treating, (5) ensure adequate formulation of products, and (6) develop a strategy for correct application.
]]>Agronomy doi: 10.3390/agronomy14030535
Authors: Xiaomei Li Nan Li Dandan Wen Jianfeng Yu Jiadu Hong Mengjie Wu Longjun Cheng Shuai Meng
NAC (NAM, ATAF and CUC)-like transcription factors, a class of plant-specific transcription factors, play a pivotal role in plant growth, development, metabolism, and stress response. Notably, a specific subclass of NAC family, known as SNAC (stress-responsive NAC), is particularly involved in the plant’s response to abiotic stress. As a very useful tree, Casuarina equisetifolia L. also has excellent stress resistance properties. To explore gene resources of C. equisetifolia which are associated with stress resistance and the molecular mechanisms that it employed is very helpful to its molecular-assisted breeding. In this study, 10 CeSNAC transcription factors were identified by constructing the phylogenetic tree of 94 CeNACs from the genome of C. equisetifolia L. together with 79 SNAC in different plant species. Phylogenetic tree analysis revealed that these 10 CeSNAC genes are classified into the ATAF (Arabidopsis transcription activation factor), NAP (NAC-like, activated by AP3/P1), and AtNAC3 subfamilies of the NAC family, all featuring the typical NAM (no apical meristem) domain, with the exception of CeSNAC7. In addition, all NAC transcription factors, except CeSNAC9, were localized in the nucleus. Examination of the CeSNAC promoter unveiled the presence of stress response elements such as a STRE (stress responsive element), an MBS (MYB binding site), an ABRE (abscisic acid responsive element) and a LTR (low temperature responsive element). Under various stress treatments, the majority of CeSNAC expressions exhibited induction in response to low temperature, drought, and high salt treatments, as well as ABA (abscisic acid) treatment. However, CeSNAC6, CeSNAC7, and CeSNAC9 were found to be inhibited specifically by drought treatment. Additionally, only CeSNAC3 and CeNAC9 expression was hindered while the rest of the CeSNAC expression were induced by MeJA (methyl jasmonate) treatment. These findings shed light on the relationship between different CeSNAC genes and their responses to abiotic stress conditions, providing valuable insights for further research into CeSNAC functions and aiding the development of stress-resistant varieties in C. equisetifolia.
]]>Agronomy doi: 10.3390/agronomy14030536
Authors: Yi Lu Jingli Xu Zhenyu Liu Yuan Chen Xiang Zhang Dehua Chen
The direct-sown cotton after wheat harvest (DSCWH) cropping system has attracted wide attention due to reduced labor inputs compared to transplanting. However, the management strategy of slow-release nitrogen is unclear in such a system. This study aims to investigate the impact of different timings and dosages of slow-release nitrogen fertilizer on the yield, biomass accumulation and distribution, and nitrogen absorption and nitrogen utilization in the DSCWH cropping system. This study was investigated at the experimental farm of Yangzhou University, China in 2020 and 2021, with the short-season cotton variety “Zhongmian 50” used as experimental material. Three dosages of the slow-release nitrogen fertilizer (45 kg·ha−1, 90 kg·ha−1, and 135 kg·ha−1) were applied at two stages of growth (two-leaf and four-leaf). The results showed that applying a 90 kg·ha−1 dosage at the two-leaf stage achieved the highest yield, which was increased by 12.6% compared to the no-fertilization control. Applying 90 kg·ha−1 of the slow-release nitrogen at the two-leaf stage promoted biomass accumulation, especially in reproductive organs, and this increase in biomass of reproductive organs was attributed to optimum nitrogen accumulation in reproductive organs (80~140 kg·ha−1). In addition, when 90 kg·ha−1 was applied at the two-leaf stage, there was a significant enhancement in nitrogen recovery efficiency (NRE), nitrogen agronomic use efficiency (NAE), and nitrogen physiological efficiency (NPE), with increases of 7.2% to 13.0%, 5.7% to 5.8%, and 5.6% to 6.5%, respectively. These results revealed that applying slow-release nitrogen fertilizer with the optimal dosage at the seedling stage could significantly enhance nitrogen use efficiency, nitrogen accumulation and partitioning, and biomass accumulation and distribution, which ultimately resulted in a higher lint yield in DSCWH. Therefore, to optimize yield and NUE, 90 kg·ha−1 slow-release nitrogen applied at the two-leaf stage would be recommended in the direct-sown cotton after wheat harvest cropping system.
]]>Agronomy doi: 10.3390/agronomy14030534
Authors: Agnieszka Klimek-Kopyra Barbara Skowera Ewa Dacewicz Elżbieta Boligłowa Bogdan Kulig Katarzyna Znój
The aim of the study was to assess the health status and seed yield of selected soybean cultivars grown in the climate conditions of Central Europe. The health of 22 soybean cultivars was assessed during the study period (2017–2022). Cultivars from two earliness classes (1 and 2) were included in order to capture the entire spectrum of variation in the degree of infection with seven fungal diseases throughout the growing season, i.e., from sowing to harvest. Based on analysis of meteorological conditions in the critical phase of soybean development (from flowering to pod formation), two distinct periods were distinguished according to temperature and rainfall: normal (2017–2019) and anomalous (2020–2022). Ward’s cluster analysis distinguished two clusters that differed in terms of the weather conditions and severity and number of diseases observed for analyzed soybean cultivars during six years of the study. The first cluster included the period 2017–2019, which was characterized as normal in terms of temperature and rainfall. The second cluster included the period 2020–2022, which was characterized as anomalous in terms of temperature and rainfall. In the normal years (2017–2019), only Fusarium of the leaves was not observed during the soybean growing period. Seven diseases were observed in the anomalous years (2020–2022), and the degree of infection of the plants was greater. The Aligator cultivar in class 2, with a longer growing period, showed the highest yield stability. In the anomalous years, yield stability was highest for the class 2 cultivar Viola and lowest for the Acardia cultivar of the same class. In the whole study period, the Abelina cultivar (class 1) had a low coefficient of variation for yield, which means that this soybean cultivar is one of the most stable in terms of yield.
]]>Agronomy doi: 10.3390/agronomy14030533
Authors: Mohammad Ghorbani Elnaz Amirahmadi Jaroslav Bernas Petr Konvalina
Biochar as a by-product of the carbonization of biomass has an inherent potential to modify acidic soils due to its alkaline nature. To explore the mechanism and effectiveness of biochar, a case study was conducted on severely acidic soils from six fields under tea cultivation in a subtropical zone, comparing rice husk biochars, in three rates (B5, B10, B15 t ha−1), and CaCO3 as conventional liming practice. The results showed increases in pH of 71.5%, 52.7%, 30.6%, and 29.7% in B15, B10, B5, and CaCO3-treated soils compared to the control. On average, B15 and B10 treatments resulted in the highest organic matter with 12.3% and 9.7%, respectively. B15, B10, B5, and CaCO3 caused increases of 196.6%, 173.4%, 129.7%, and 100.9% in base saturation compared to the control, respectively. Also, after the application of B15, B10, and B5 treatments, the effective cation exchange capacity increased by 191.4%, 112.1%, and 39.5%; however, the application of CaCO3 resulted in a 20.1% decrease. Overall, applying biochar on acidic soils provides adequate negative charges due to its well-extended specific surface area and pore volume, which cause the absorption of additional Al+, resulting in ameliorating soil pH. The application of proper biochar could notably be more effective in improving acidic soils than conventional practices such as the overuse of CaCO3. In this regard, evaluating various biochars in terms of feedstock, pyrolysis conditions, and modification scenarios merits in-depth research in future studies.
]]>Agronomy doi: 10.3390/agronomy14030532
Authors: Sevim Seda Yamaç Bedri Kurtuluş Azhar M. Memon Gadir Alomair Mladen Todorovic
This study examined the performance of random forest (RF), support vector machine (SVM) and adaptive boosting (AB) machine learning models used to estimate daily potato crop evapotranspiration adjusted (ETc-adj) under full irrigation (I100), 50% of full irrigation supply (I50) and rainfed cultivation (I0). Five scenarios of weather, crop and soil data availability were considered: (S1) reference evapotranspiration and precipitation, (S2) S1 and crop coefficient, (S3) S2, the fraction of total available water and root depth, (S4) S2 and total soil available water, and (S5) S3 and total soil available water. The performance of machine learning models was compared with the standard FAO56 calculation procedure. The most accurate ETc-adj estimates were observed with AB4 for I100, RF3 for I50 and AB5 for I0 with coefficients of determination (R2) of 0.992, 0.816 and 0.922, slopes of 1.004, 0.999 and 0.972, modelling efficiencies (EF) of 0.992, 0.815 and 0.917, mean absolute errors (MAE) of 0.125, 0.405 and 0.241 mm day−1, root mean square errors (RMSE) of 0.171, 0.579 and 0.359 mm day−1 and mean squared errors (MSE) of 0.029, 0.335 and 0.129 mm day−1, respectively. The AB model is suggested for ETc-adj prediction under I100 and I0 conditions, while the RF model is recommended under the I50 condition.
]]>Agronomy doi: 10.3390/agronomy14030531
Authors: Nicolò Montegiove Alberto Maria Gambelli Eleonora Calzoni Agnese Bertoldi Debora Puglia Claudia Zadra Carla Emiliani Giovanni Gigliotti
At present, taking into account the sustainability of the starting matrices, the biogas production industry is continuously growing, especially in consideration of ecological transition and circularity. The present study deals with the development of anaerobic bioreactors aimed at valorizing two specific wastes of the olive oil supply chain, i.e., the residual of protein hydrolysis process of three-phases olive pomace (OP-PH) and that recovered after the extraction of bioactive molecules from olive mill wastewater (OMWW waste). The energy consumed for biogas production varied from 0.52 kJ (OP and OMWW waste) to 0.97 kJ (OP-PH), while the energy produced for OP, OP-PH and OMMW waste was equal to 1.73, 2.94 and 1.60 kJ, respectively. The optimal production period was defined by considering only the range showing energy production higher than its consumption. According to this, OMWW showed the best performances, since it required 9 days (instead of 12 of untreated and treated OP) to reach the completion. The biogas production efficiency of the three-phase OP-PH waste calculated in the optimal production period, i.e., 12 days, was higher than the other samples, with a yield of 76.7% and a quantity of energy potentially producible corresponding to 1727.8 kJ/kg of volatile solids. These results pave the way for possible applications of this procedure for the planning of a multi-purpose biorefinery fed with by-products from the olive supply chain waste, thus promoting the use of sustainable waste materials from a circular economy perspective.
]]>Agronomy doi: 10.3390/agronomy14030530
Authors: Xiaoping Zang Tianyan Yun Lixia Wang Rulin Zhan Zheli Ding Weihong Ma Mamdouh A. Eissa Tao Jing Yongxia Liu Jianghui Xie Yingdui He
Reducing fertilizer doses under sustainable agricultural management is possible by increasing nutrient utilization efficiency, which will decrease crop production costs and boost economic return. Soil amendments known as water retention agents (WRAs) are added to the soil to enhance crop growth conditions. We hypothesize that the addition of WRAs may support the soil-retaining nutrients given through fertilization and prevent them from leaching into tropical soils characterized by severe rainfall due to WRAs’ exceptional capacities to absorb and store water. Mango trees (Mangifera indica L. cv Tainong No. 1) aged 18 years were fertilized with 100% or 80% of the recommended doses of nitrogen (N), phosphorus (P), and potassium (K). The experimental design included three treatments, i.e., complete recommended doses of N, P, and K (CRF), 80% of the complete recommended doses (RRF), and water-retaining agent (40 kg ha−1) + 80% of the complete recommended doses (WRARRF). Reducing the fertilization doses by 20% for mango trees in the studied tropical soil significantly (p < 0.05) minimized the nutrient availability in the soil compared to the complete fertilization doses. WRARRF compensated for the nutrient reduction by increasing the availability of N, P, and K. The addition of WRARR increased N, P, and K in mango leaf by 11%, 4%, and 7% in the first year and by 11%, 6%, and 7% in the second year, respectively, compared to CRF. The addition of WRARR increased the partial fertilizer productivity (PFP) value by 36% and 41% in the first and second years, respectively. The highest mango fruit output was achieved by the addition of WRARRF, which resulted in increases in mango fruit yield of 11.9% and 16.5% in the first and second years, respectively, compared to RRF. Fruit quality traits showed the descending order: WRARRF > RRF > CRF. WRARRF produced the maximum economic benefit (USD 7372 per hectare) compared to CRF and RRF. The polyacrylamide/attapulgite water-retaining agent exhibited remarkable improvement in mango fruit yield and economic profit by regulating the release of nutrients in tropical soils. Water-retaining agents are an effective strategy for overcoming the extensive fertilization used in mango orchards, which has resulted in numerous environmental contaminations and the inefficient use of fertilizers.
]]>Agronomy doi: 10.3390/agronomy14030529
Authors: Feng Wu Xin Li Xuemei Liu Songmei Zai Linbao Liu Danting Liu Huanyu Wei Jing Huang Xingjie Gao
To investigate the effect of nitrogen application and soil microbial activity on the decomposition process of stalk material in stalk composite pipes (SCPs) under subsurface irrigation with stalk composite pipes (SSI), in this study, a field experiment was conducted with two fertilization strategies—banding fertilization and SCP fertigation—at three nitrogen doses (126, 168, and 210 kg/ha), and the Biolog Ecoplate™ was employed to determine soil microbial activity. The results showed that under banding fertilization, the soil microbial activity at 20 cm subsoil and at the SCP wall increased with the increase in nitrogen dosage, ranging from 37.6% to 54.3% and from 21.5% to 23.7%, respectively. Under SCP fertigation, the soil microbial activity at 20 cm subsoil first showed a 58% surge, followed by a 3.9% decrease, with no significant variation in soil microbial activity at the SCP wall. Forty-five days later, the crude fiber content in the SCP wall under SCP fertigation was 17.6–26.3% lower than that under banding fertilization. Based on the comprehensive analysis of the soil microbial activity, SCP fertigation combined with high nitrogen application can accelerate the decay rate of straw in SCPs. This research can provide a reference for formulating irrigation and fertilization regimes for SSI.
]]>Agronomy doi: 10.3390/agronomy14030528
Authors: Christian Frasconi Marco Fontanelli Daniele Antichi
Current trends in modern farming systems are moving in the direction of technical solutions for improving the sustainability and biodiversity of agroecosystems [...]
]]>Agronomy doi: 10.3390/agronomy14030527
Authors: Liang Feng Yun Hu Kai Shi Haiying Tang Tian Pu Xiaochun Wang Wenyu Yang
In order to reveal the yield-increasing mechanism of relay intercropping (RI) maize with different varieties from the perspective of plant growth, source sink relationship, and root growth, a two-factor randomized block design trial was designed, which includes different maize varieties (Rongyu1210 (RY1210), Zhongyu 3 (ZY3)) and plant pattern (RI, Sole cropping (SC)). The leaf area index (LAI), dry matter accumulation and distribution, root dry weight (RDW), root length (RL), root surface area (RSA), root volume (RV), and maize yield were determined. LAI of RI RY1210 was significantly higher than that of the SC RY1210 at the filling stage and maturity stage. The dry matter accumulation of RI RY1210 ear was significantly higher than that of SC RY1210 and RI ZY3, and the RDW of RY1210 was significantly higher than that of ZY3. The ratio of RDW of RI RY1210 was higher than that of RI ZY3 in the 20–40 and 40–60 cm soil layers, respectively. The RDW, RL, RV, and RSA of RI RY1210 were significantly lower than that of sole RY1210 by 25.43%, 10.75%, 30.79%, and 23.73%, respectively, but higher than that of RI ZY3 by 143.98%, 278.29%, 54.40%, and 29.57%, respectively. The average yield of RI RY1210 was 8782.71 kg ha−1, with no significant difference compared to SC, which was mainly attributed to a larger ear dry matter accumulation, higher LAI in later growth stages, larger RDW, and the ratio of roots in deeper soil layers. This study will be useful and helpful to farmers for how to select and plant high-yielding maize varieties in strip relay intercropping.
]]>Agronomy doi: 10.3390/agronomy14030526
Authors: Zhen Meng Shuangshuang Xiang Xue Wang Jian Zhang Guoxin Bai Hongjun Liu Rong Li Qirong Shen
Trichoderma is a widely recognized plant-growth-promoting fungus that has been extensively utilized in various agricultural applications. However, research on the economic production of Trichoderma spores and their effects on tea cuttings must be further advanced. In this study, T. guizhouense NJAU 4742 (NJAU 4742) emerged as a growth-promoting strain for tea cuttings, and the spore-production conditions of NJAU 4742 attained through solid-state fermentation (SSF) using tea residues were optimized. In a pot experiment, nursery substrates containing different concentrations of NJAU 4742 spores were tested for their influence on tea cutting growth and the rhizosphere fungal community. The optimal conditions for spore yield were determined as a 7:3 (w/w) ratio of tea residue to rice bran, a material thickness of 3 cm, an inoculum concentration of 15% (v/w), and an incubation time of 4 days, resulting in a spore count of 1.8 × 109 CFU/g. Applying NJAU 4742 spore products significantly increased the biomass of tea cuttings and influenced the fungal community composition. Moreover, higher concentrations of NJAU 4742 spores yielded better growth performance, and applying nursery substrate with 1.0 × 107 CFU/mL spores was the most economically viable option. Notably, among the top ten fungal genera with the highest relative abundance, Trichoderma showed a positive correlation with the fresh weight of tea cuttings, while the others exhibited a negative correlation. Overall, utilizing tea residue for SSF to produce NJAU 4742 was a feasible approach, and the application of NJAU 4742 spores enhanced the growth of tea cuttings by increasing the relative abundance of Trichoderma.
]]>Agronomy doi: 10.3390/agronomy14030524
Authors: Luis F. Mateo M. Isabel Más-López Eva M. García-del-Toro Sara García-Salgado M. Ángeles Quijano
Groundwater is a crucial water resource, particularly in regions with intensive agriculture and a semi-arid climate, such as Campo de Cartagena (Murcia, Spain). Groundwater salinity in the area can be attributed to hydrogeological characteristics, irrigation return water, or even marine intrusion and communication between aquifers. The management of these waters is essential to maintain sustainable agriculture in the area. Therefore, two groundwater salinity prediction models were developed, a backpropagation artificial neural network (ANN) model and a multiple linear regression (MLR) model, based on EC (electrical conductivity) data obtained from official information sources. The data used were the bicarbonate, calcium, chloride, magnesium, nitrate, potassium, sodium, and sulphate concentrations, as well as EC, pH, and temperature, of 495 water samples from 38 sampling stations between 2000 and 2023. Variables with the least influence on the model were discarded in a previous statistical analysis. Based on seven evaluation metrics (RMSE, MAE, R2, MPE, MBE, SSE, and AARD), the ANN model showed a sligntly better accuracy in predicting EC compared to the MLR model. As a result, the ANN model, together with crop tolerance to EC, may be an effective tool for groundwater irrigation management in these areas.
]]>Agronomy doi: 10.3390/agronomy14030525
Authors: Xuepeng Wu Junjie Wu Bingqian Zhou Bo Hong Dongfang Zhao Mei Guan
In order to explore the effect of fertilization patterns on the growth of rapeseed seedlings under waterlogging stress, three fertilization patterns (conventional fertilization, supplemental organic fertilization, and supplemental microbial fertilization) were set up using the variety Xiangyou 708 as the material, and waterlogging treatment was carried out during the seedling stage of rapeseed. The effects of fertilization patterns on the growth of rapeseed seedlings and rhizosphere microorganisms under waterlogging stress were investigated. The results showed that all three fertilization patterns exhibited that waterlogging stress inhibited the growth of rapeseed seedlings, inhibited root activity, and changed the structure of rhizosphere bacterial community structure. However, supplemental organic and microbial fertilization better promoted the growth of rapeseed seedlings, reduced the impact of waterlogging stress on the growth of rapeseed seedlings, and accelerated the recovery of rapeseed seedlings after waterlogging stress. Under normal water supply, supplemental organic fertilization enriched P_Bacteroidota, P_Actinobacteriota, P_Chloroflexi, and G_Flavisolibacter in the rhizosphere soil of rapeseed, while supplemental microbial fertilization enriched P_Bacteroidota and G_Flavisolibacter in the rhizosphere soil of rapeseed. After 7 days of waterlogging treatment, supplemental organic fertilization enriched P_Verrucomicrobiota in the rhizosphere soil of rapeseed, while supplemental microbial fertilization enriched P_Actinobacteriota, G_SC-I-84, and G_Ellin6067 in the rhizosphere soil of rapeseed. The enrichment of these bacteria may be related to the growth promotion and waterlogging tolerance of rapeseed. This study provides evidence that microbial and organic fertilizer can promote the growth of rapeseed and enhance its waterlogging tolerance, as well as evidence that some rhizosphere microorganisms have a potential role in promoting the growth and waterlogging tolerance of rapeseed.
]]>Agronomy doi: 10.3390/agronomy14030523
Authors: Yuxuan Wang Zhongyi Qu Wei Yang Xi Chen Tian Qiao
Soil salinization is a global issue confronting humanity, imposing significant constraints on agricultural production in the irrigated regions along the southern bank of the Yellow River. This, in turn, leads to the degradation of the ecological environment and inadequate grain yields. Hence, it is essential to explore the magnitude and spatial patterns of soil salinization to promote efficient and sustainable agricultural development. This study carried out a two-year surface soil sampling experiment encompassing the periods before spring irrigation and the budding, flowering, and maturity stages of sunflower fields in the irrigated area along the southern bank of the Yellow River. It employed deep learning in conjunction with multispectral remote sensing conducted by UAV to estimate soil salinity levels in the sunflower fields. Following the identification of sensitive spectral variables through correlation analysis, we proceeded to model and compare the accuracy and stability of various models, including the deep learning Transformer model, traditional machine learning BP neural network (BPNN), random forest model (RF), and partial least squares regression model (PLSR). The findings indicate that the precision of soil salinity content (SSC) retrieval in saline–alkali land can be significantly enhanced by incorporating the RE band of UAV data. Four SSC inversion models were developed using the most suitable spectral variables, resulting in precise soil salinity inversion. The model order based on accuracy and stability was Transformer > BPNN > RF > PLSR. Notably, the Transformer model achieved a prediction accuracy exceeding 0.8 for both the training and test datasets, as indicated by R2 values. The precision order of the soil salinity inversion model in each period is as follows: before spring irrigation > budding period > maturity period > flowering stages. Additionally, the accuracy is higher in the bare soil stage compared to the crop cover stage. The Transformer model exhibited RMSE and R2 values of 2.41 g kg−1 and 0.84 on the test datasets, with the salt inversion results aligning closely with field-measured data. The results showed that the Transformer deep learning model integrated with RE band data significantly enhances the precision and efficiency of soil salinity inversion within the irrigated regions along the south bank of the Yellow River.
]]>Agronomy doi: 10.3390/agronomy14030522
Authors: Longmei Wu Keru Yu Jixiang Zou Xiaozhe Bao Taotao Yang Qingchun Chen Bin Zhang
Precision hill-drop direct seeding using mechanical drilling is a unique direct seeding technique employed in south China that offers advantages such as excellent grain yield and high lodging resistance. Improving yield and lodging-related traits is essential for efforts to improve mechanically direct-seeded rice (MDSR) production. Seeding rates (SR) and nitrogen (N) fertilization rate are two of the main factors affecting grain yield and lodging resistance under MDSR production. However, little information about double-season MDSR production in south China is available. Here, we evaluated yield and lodging risk for two rice cultivars Huanghuazhan, HHZ, lodging-resistant; Xiangyaxiangzhan, XYXZ, lodging-susceptible across two consecutive growing seasons under two under two seeding rates (LSR, 30 cm × 18 cm; HSR, 30 cm × 12 cm) and three N fertilization rates (N1 = 100 kg ha−1, reduced N; N2 = 150 kg ha−1, normal N; and N3 = 200 kg ha−1, enhanced N). We found that increased SR and N fertilization rate improved grain yield and increased lodging risk. SR and N were consistently and positively related to plant height (PH), gravity center height (GCH), the length from the broken basal internode to the panicle tip (SL), the fresh plant weight of the plant part above the broken point (FW), and the length of the two basal internodes. SR and N decreased breaking force (F) and breaking strength (BM), driving increased lodging risk as reflected by increases in lodging index (LI) values. Culm diameter (CD) and culm wall thickness (CWT) did not respond consistently to SR and N treatments. Correlation analysis revealed that PH, GCH, the length of first and second basal internodes, FW, and bending moment for the whole plant (WP) were positively correlated with LI, while F and BM were negatively associated with LI. These findings suggest that the increased lodging risk resulting from high SR could be mitigated by applying appropriate rates of N; that is, this work suggests that grain yield can be maximized and lodging risk minimized by increasing SR while decreasing N fertilization rate. Seasonal differences in the effects of SR and N fertilization should be considered to achieve a high grain yield and maintain high lodging resistance. Our study suggests that increasing SR and decreasing N fertilization can enhance rice grain yield while improving lodging resistance for both varieties. Optimizing grain yield by increasing SR while reducing lodging risk by lowering N application rates may maintain lodging resistance and improve grain yield.
]]>Agronomy doi: 10.3390/agronomy14030521
Authors: Yanbo Yang Qihang Cai Yimei Wang Liping Li Zhenghai Sun
The WD40 gene family is a highly conserved protein family in plants that plays a crucial role in various life activities. Although eggplant (Solanum melongena L.) genome sequencing has been completed, there is limited research on the WD40 family in eggplant, and the regulatory mechanism of its involvement in anthocyanin synthesis remains poorly understood. The research identified the eggplant WD40 gene family, comprising 187 SmWD40 members that are unevenly distributed across 12 chromosomes of the eggplant. Phylogenetic analysis classified them into 11 subgroups, with members within the same subgroup having similar motifs and gene structures. The promoter of the SmWD40 genes contains a high number of light, stress, and hormone response elements. The expression patterns of 20 SmWD40 members of the S5 subgroup were analyzed during the formation of fruit color in long purple eggplant. Subsequently, we used virus-induced gene silencing (VIGS) to confirm the significance of the TTG1 (SmWD40-56) gene in subgroup S5 for anthocyanin synthesis in eggplant fruit. To investigate the molecular mechanism of SmWD40-56 in eggplant fruit color formation, we analyzed the expression patterns of structural genes for anthocyanin synthesis in eggplant fruit silenced for SmWD40-56. Finally, we predicted the protein interaction network of the SmWD40-56 gene to understand its potential regulatory mechanisms. The result showed that SmWD40-56 may regulate the structural genes involved in anthocyanin biosynthesis and plays an important role in eggplant fruit color formation. This study provides some basis for studying the mechanism of eggplant fruit color formation.
]]>Agronomy doi: 10.3390/agronomy14030520
Authors: María Josefina Buonocore-Biancheri Lorena del Carmen Suárez Segundo Ricardo Núñez-Campero Marcos Darío Ponssa Flávio Roberto Mello Garcia Daniel Santiago Kirschbaum Sergio Marcelo Ovruski
Drosophila suzukii (Matsumura) is an invasive pest mainly affecting berry and stone fruit crops worldwide. In Argentina, it inhabits fruit-growing regions. An eco-friendly management strategy involves biological control by using resident natural enemies, such as the Neotropical-native pupal parasitoid Trichopria anastrephae Lima (Ta). The study compared the host-killing capacity and the offspring reproductive success of two Ta lineages on the puparia of both D. suzukii (Ds) and D. melanogaster (Dm) in no-choice and choice tests under laboratory conditions. The host preference and host-switching behaviors were also assessed. One parasitoid lineage was reared on Ds (TaDs), and the second on Dm (TaDm). In no-choice tests, both Ta lineages performed similarly on both hosts regarding the percentage of killed hosts and parasitoid offspring survival. The host-killing ability of TaDm was only significantly lower when Ds was offered as a host, relative to Dm. In choice tests, Ta attacked mainly Ds at a 4–9 times Ds to Dm ratio, but at a 1.5–2 times Ds to Dm ratio, the host-killing ability was similar between both drosophilids. At an equal host ratio or higher Dm ratios, Ta preferred the native host. However, it was determined that Ta has the potential to parasitize the recently-introduced pest.
]]>Agronomy doi: 10.3390/agronomy14030519
Authors: Wenchao Li Peng Xu Cheng Qian Xing Zhao Huini Xu Kunzhi Li
The flowering of Amorphophallus bulbifer (A. bulbifer) plays an important role in its reproduction. The flowers and leaves of A. bulbifer cannot grow at the same time. However, the physiological and molecular mechanisms involved in flower bud and leaf bud formation are still unclear. In this study, the flower buds and leaf buds of A. bulbifer in the early stage of growth were used as research materials, transcriptome and metabolome analyses were carried out, and the soluble sugar and starch contents of A. bulbifer corms were determined. Transcriptome analysis revealed 5542 differentially expressed genes (DEGs) between flower buds and leaf buds, 3107 of which were upregulated and 2435 of which were downregulated. Enrichment analysis of the KEGG pathway showed that these differential genes were enriched mainly in the plant hormone signal transduction, DNA replication and fatty acid elongation pathways. A total of 5296 significant differentially abundant metabolites were screened out by nontargeted metabolomics analysis. The differentially abundant metabolites were functionally classified in the HMDB, and 118 were successfully matched, including 17 that were highly expressed in flower buds. The differentially abundant metabolites in the flower buds were mainly enriched in pathways such as amino acid metabolism, isoquinoline alkaloid biosynthesis and pyrimidine metabolism. Targeted metabolomics analysis revealed that the contents of ABA, ZT and iPA in flower buds were significantly greater than those in leaf buds, while the opposite trend was observed for IAA. The analysis of soluble sugar and starch contents showed that the starch and soluble sugar contents in flower buds were significantly greater than those in leaf buds. The results of this study showed that flower bud development in A. bulbifer was regulated by amino acids, starch, ABA, ZT, iPA, IAA and other hormones. These findings could lead to valuable genetic resources for further study of A. bulbifer flowering and provide a deeper understanding of the molecular basis of A. bulbifer flowering.
]]>Agronomy doi: 10.3390/agronomy14030518
Authors: Francesco Barreca
The world’s population is expected to increase by nearly two billion in the next 30 years; the population will increase from 8 billion to 9.7 billion by 2050 and could peak at 10.4 billion by the mid-2080s. The extreme weather triggered by global climate change has severely hit crop yields in open-field cultivation and led to an increase in food prices. Furthermore, in the last few years, emergency events such as the COVID-19 pandemic, wars/conflicts, and economic downturns have conditioned agricultural production and food security around the world. Greenhouses could be efficient cultivation systems because they enable food production in a sustainable way, limiting contact between pollutants and plants and optimizing the use of water, energy, and soil. This paper proposes a novel dome-soilless greenhouse concept for tomato cultivation in the Mediterranean area. The proposed greenhouse is fixed on a sea platform to take advantage of the seawater cooling environment and to integrate water consumption into a hydroponic system. In order to evaluate the best covering solution material to adopt, a few thermal and photometric characteristics of greenhouse covering materials were evaluated using a simplified method. A dynamic simulation was carried out to compare the proposed seawater cooling system with a conventional cooling tower in terms of the electric energy spent to maintain the inside temperature range at 13–25 °C across all seasons in the year. The proposed heating, ventilation, and air conditioning (HVAC) system allowed a total annual energy saving of more than 10%. The energy saved was a result of the better cooling performance of the seawater heat exchange that allowed energy saving of about 14% on cooling. The comparison between the model characterised by a 6 mm polycarbonate coupled with UbiGro film and a seawater cooling system, and the model including a 6 mm polycarbonate coupled with a clarix blue film covering and a tower cooling system highlighted energy saving of about 20%. The obtained results indicate possible future directions for offshore greenhouses to carry out independent production together with the integration of photovoltaic modules, water treatment plants, and smart remote-control systems.
]]>Agronomy doi: 10.3390/agronomy14030517
Authors: Jaime Barros Silva Filho Paulo C. R. Fontes Jorge Freire da Silva Ferreira Paulo R. Cecon Marllon Fernando Soares dos Santos
Although plant characterization under the International Potato Center’s (CIP’s) aeroponic system requires many morpho-physiological parameters to evaluate a cultivar, there is no method to evaluate the best parameters or the most suitable cultivation time. Thus, several morpho-physiological parameters were compared under a modified aeroponic system, using different statistical tools, to determine the best parameters and most efficient time to characterize seed-potato plants. We evaluated 21 parameters for cv. Agata under a randomized complete block design with weekly harvests for 9 weeks. The best parameters for growth characterization were selected based on multivariate statistical approaches involving correlation plots, similarity clusters (dendrograms), and principal component analysis. The best parameters for seed potato characterization were as follows, in order of importance: main stem diameter, leaf number, the length of the fourth leaf, leaf area, number of mini-tubers, mini-tuber fresh weight, root dry weight, and total dry weight. The days after transplanting (DAT) significantly affected the morpho-physiological parameters, with 45 DAT being the best cultivation time to estimate mini-tuber yield, and the data for bi-weekly harvests were as reliable as for weekly harvests. Our results, applied to either the CIP or to our modified aeroponics method, will be valuable in streamlining the characterization of other seed potato cultivars used by certified producers.
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