Agronomy doi: 10.3390/agronomy16161544

Authors: Mohammad Aldossary Ibrahim Alzamil Jaber Almutairi

Accurate weed detection is essential for site-specific weed management because uncontrolled weeds compete with crops for water, nutrients, light, and growing space, while uniform herbicide application increases production costs and environmental pressure. Existing UAV-based weed detection methods remain limited by three core gaps: inadequate representation of heterogeneous and imbalanced UAV-derived agricultural records, insufficient joint modeling of crop–weed visual similarity and weed-scale variation, and evaluation protocols that rarely assess complete multi-label agreement together with field perturbations and cross-dataset transfer. To address these gaps, this study proposes AgroWeed-MCANet, a multi-scale convolutional attention network for UAV-based multi-label weed detection. Robust feature refinement and compact feature-map arrangement stabilize heterogeneous inputs; convolutional patch encoding, multi-scale ConvNeXt extraction, dilated context aggregation, channel–spatial attention, and cross-scale fusion address local ambiguity, scale variation, and noisy sensing conditions; and the Multi-Label Agreement Score (MLAS), robustness analysis, and cross-dataset evaluation provide field-oriented performance validation. Experiments were conducted on the UAV-UndesirablePlant-UK dataset containing 209,600 labeled field observations with naturally imbalanced crop and weed categories. AgroWeed-MCANet achieved 96.9% accuracy, 95.8% precision, 95.2% recall, 95.5% F1-score, and a 0.912 multi-label agreement score, outperforming twelve recent UAV-based weed detection baselines. Robustness analysis showed stable performance under missing observations, illumination shifts, altitude variations, and 20% noise, with the model maintaining 95.3% accuracy and 93.8% F1-score. Cross-dataset evaluation on DeepWeeds and CWFID further confirmed its transferability, with accuracies of 91.8% and 90.9%, respectively. These findings demonstrate that AgroWeed-MCANet supports reliable UAV-assisted weed monitoring and contributes to sustainable, site-specific weed management in precision agriculture.

Agronomy doi: 10.3390/agronomy16161543

Authors: João Serrano Francisco J. Moral Shakib Shahidian Henrique Pinto Luís L. Paniagua Emanuel Carreira Rui Charneca Alfredo Pereira

Extensive livestock farming is characteristic of the landscape of the Mediterranean regions of Southern Iberian Peninsula. These production systems based on dryland pastures provide a wide range of services and contribute to maintaining environmental balance when compared with intensive agricultural or other livestock production systems. The Portuguese Montado is a habitat of Community importance and is protected under the European Natura 2000 network. This makes any research aimed at preserving, maintaining, or restoring this ecosystem particularly important to ensure its sustainable management. The main objectives of this study were to evaluate: (i) the impact of dolomitic limestone application on soil pH; (ii) the relation between multiple soil parameters; (iii) the impact of grazing preferences and livestock stocking rates on topsoil compaction; (iv) temporal and spatial sheep grazing patterns and sward productivity, quality and floristic composition throughout the growing vegetative season. This study was carried out during the vegetative cycle of 2023/2024 on a 4-ha pasture field located at Mitra farm (Southern Portugal). The experimental design included four treatments resulting from the combination of limestone application (with and without) and stocking rate (traditional: 7 sheep ha−1; high: 18 sheep ha−1). Sheep grazing preferences, soil compaction and fertility, sward productivity, quality and floristic composition were monitored at 48 sampling areas. The results confirm that improving soil pH through the application of dolomitic limestone is an effective, although slow and gradual process. When combined with grazing management through increased stocking rates, several important outcomes were observed: (i) preferential grazing areas did not exhibit significant differences in soil trampling; (ii) higher stocking rates resulted in less selective grazing; (iii) soil amendment and higher livestock stocking rates contributed to greater pasture crude protein content; and (iv) the influence of pasture quality on grazing preferences depended on the phase of the pasture-grazing cycle. Overall, these findings are promising indicators of sustainability for extensive animal production in Mediterranean dryland silvopastoral systems. However, with regard to the sward, as this study only monitored a single growing season, will need to be validated in future studies.

Agronomy doi: 10.3390/agronomy16161542

Authors: Run Xue Yue Jiang Hong Li Imran Ali Lakhiar Junjun Ran

To address the limited synergy between integrated water–fertilizer technologies and intelligent application equipment, as well as the low water–nitrogen use efficiency in rapeseed production systems in southwestern China—which together constrain the large-scale adoption of smart fertigation equipment—this study conducted a two-season field experiment using an integrated water–fertilizer application system. The experiment included two irrigation regimes (W1: 60% ETc; W2: 100% ETc) and three nitrogen rates (F1: 220, F2: 300, F3: 360 kg N ha−1), plus a rainfed control (CK), to quantify rapeseed responses to water–nitrogen interactions under an equipment-based fertigation framework. Results showed that water–nitrogen interactions significantly regulated rapeseed physiological processes, growth, yield formation, and resource-use efficiency. Compared with CK, appropriate water and nitrogen supply markedly enhanced PSII efficiency and overall energy conversion. In particular, W2F2 increased leaf photosynthetic rate by 51.2% and 50.8% across the two seasons. Water–nitrogen coupling also improved yield components such as branch number and thousand-seed weight, thereby increasing final yield. Although nitrogen partial factor productivity declined with increasing N rates, smart fertigation improved economic returns to varying degrees. EWM-TOPSIS results indicated that W2F2 consistently achieved the highest comprehensive performance across both seasons. By balancing yield, seed quality, resource efficiency, and economic benefit, this treatment represents the optimal strategy under intelligent fertigation systems. Overall, this study provides a decision-oriented optimization framework based on crop physiological responses under smart water–fertilizer equipment, offering practical guidance for intelligent fertigation deployment in rapeseed systems in southwestern China.

Agronomy doi: 10.3390/agronomy16161541

Authors: Kailun Song Chulan Sun Rong Hu Ting Guo Zhen Huang Fei Wang Xin Yin Chunhuo Zhou Guorong Ni

Purpose: The temporal effectiveness of double-cropping rice systems in southern China is limited by the slow natural decomposition rate of straw, which represents a crucial ecological bottleneck. This study reports on two consecutive pot experiments—one conducted in the 2019 late-rice season (cultivar: Tianyou Huazhan) and the other in the 2020 early-rice season (cultivar: Taiyou 98)—to investigate how the straw-decomposing microbial inoculant JN01 influences rice growth, microbial community traits, and soil biochemical properties under equal-nutrient straw incorporation. Methods: This study conducted pot experiments from 2019 to 2020 using the self-developed straw-decomposing microbial agent JN01 (J) as the test material. Under the condition of equal nutrients, the experiment of conventional chemical fertilization (CK) and straw returning to field (SF) was set up. Results: The application of JN01 significantly boosted the soil’s capacity to transform nutrients, as indicated by the increases of 77.50% and 69.16% in soil alkali-hydrolyzable nitrogen throughout the tillering and heading stages, respectively. It aided in the conversion of organic phosphorus in straw to effective phosphorus in soil, significantly increasing soil fungi (241.87%) and actinobacteria (93.10%) at maturity, optimizing the fungi/bacteria ratio, promoting the microbial community transition from bacterial to fungal dominance, improving soil cellulose degradation ability, and improving nitrogen transformation capability. Conclusions: This pot study clarifies the regulating mechanism of JN01 on soil microenvironment and offers theoretical support for the use of straw resources in southern double-cropping rice systems. Under controlled pot circumstances, the inoculant demonstrated potential to optimize straw-related nutrient transformation and coordinate rice yield components; nevertheless, field verification is necessary for large-scale practical implementation.

Agronomy doi: 10.3390/agronomy16161540

Authors: Run Xue Xinyu Li Haofang Yan Imran Ali Lakhiar Junjun Ran Chuan Zhang

Micro-sprinkler irrigation is commonly used to optimize plant growing environments and prevent growth inhibition and yield losses caused by high air temperatures (Ta) in greenhouses. Nevertheless, instantaneous photosynthetic rate measurements suffer from time lag, and the temporally dynamic microclimate alterations induced by micro-sprinkling make it difficult to reproduce the real ambient conditions for crop growth. Therefore, two treatments, namely micro-sprinkling combined with drip irrigation (MSDI) and conventional drip irrigation control (DI), were established in a Venlo-type greenhouse. Continuous chlorophyll fluorescence (ChlF) monitoring combined with rapid light curves under fixed photosynthetically active radiation was adopted to investigate the diurnal alleviation effects of micro-sprinkling on tomatoes under high-temperature stress. This study found that ΦPSII was more sensitive than Fv/Fm in detecting changes in PSII photochemical performance under high-temperature stress. Micro-sprinkling showed greater mitigation effects under moderate heat stress, with the highest enhancement in ΦPSII (approximately 0.12) observed when leaf temperature (Tl) was around 34.5 °C. However, the improvement effect decreased under extreme heat conditions, and ΦPSII increased by only 0.017 when Ta exceeded 38 °C. The slope of the fitted line between ΦPSII and PAR on sunny days increased with increasing heat stress, indicating the enhanced sensitivity of PSII photochemical regulation to thermal stress. Compared with DI, MSDI increased tomato yield by 31.2% and 47.6% in 2021 and 2022, respectively, while improving fruit quality by increasing single fruit weight, fruit shape index, and soluble sugar content. In addition, MSDI increased SPAD, Fv/Fm, ΦPSII, and ETR by 9.6–15.6%, 8.8–14.8%, 10.3–13.3%, and 10.3–19.6%, respectively, indicating improved PSII photochemical performance under high-temperature conditions. In conclusion, micro-sprinkling mitigated part of the negative effects of high-temperature stress and significantly improved tomato yields and fruit quality, which could be used in agricultural production.

Agronomy doi: 10.3390/agronomy16161539

Authors: Huiying Zheng Ruoshui Wang Xin Wang Lisha Wang Li Chen

In semi-humid loess regions, young apple–soybean alley-cropping is constrained by water competition and phenolic accumulation, but how emitter-line layout reorganizes soil biochemical environment remains unclear. This study evaluated whether locally used management systems differed in the spatial coupling of phenolic load, biological activity, and productivity. A two-year field experiment compared rainfed apple monoculture, rainfed soybean monoculture, rainfed apple–soybean alley-cropping, and drip-irrigated alley-cropping with one emitter line per soybean row (DL1), per two rows (DL2), or per three rows. Drip-irrigated monoculture was not included because monocultures are generally rainfed locally owing to lower water demand relative to regional precipitation. Soil phenolics, enzyme activities, microbial abundances, yield, and WUE were assessed using spatial profiling, PLS-SEM, SHAP-based model interpretation, and a network-informed soil quality index (SQI). Drip-irrigated alley-cropping, particularly DL1 and DL2, was associated with lower phenolic load and higher biological activity than rainfed systems. Under DL treatments, phenolics were concentrated mainly in the 40–60 cm layer, whereas enzymes and microorganisms remained enriched in the 0–20 cm layer and shifted horizontally away from the tree row, indicating reduced spatial overlap between chemical constraints and biological activity. Productivity was more closely associated with microbial abundance under rainfed conditions but with enzyme activity under drip irrigation. The network-informed SQI discriminated treatments more clearly than conventional indices. DL1 had the highest SQI, whereas DL2 achieved the highest productivity. Among locally relevant systems, DL2 provides a practicable emitter-line layout that balances soil biochemical improvement with crop productivity.

Agronomy doi: 10.3390/agronomy16161538

Authors: Rini Dwi Wahyuni Erich M. Pötsch Yuri Katagiri Dalmoro Pedro Sessegolo Ferzola Martin Gierus

Permanent grassland management commonly includes moderate mineral N fertilization, which can differentially affect botanical composition, dry matter (DM) yield and forage quality of grasses, legumes and forbs. We hypothesized that increasing N would enhance grass dominance and DM yield but raise fiber and reduce metabolizable energy (ME) content. We evaluated long-term N fertilization, cutting time and their interaction on DM yield and ME of grasses, legumes and forbs in a permanent mountain grassland. The field experiment, established in 1967, used a randomized block design (4 replicates, 3 cuts/year) with five treatments: unfertilized (Control), PK without N (N0), and PK plus 80 (N80), 120 (N120) or 180 (N180) kg N/ha per year; forage was sampled in 2014–2016. Increasing N raised grasses to ~92% of biomass at N180 and reduced legumes and forbs (p < 0.001). Mean DM yield rose from 2.5 (Control) to 9.8 t/ha (N180; p < 0.001). High N (N120, N180) lowered ME of grasses in later cuts (8.9 vs. 10.1 MJ/kg DM in the third cut), whereas legumes and forbs maintained high ME. Moderate N fertilization (80–120 kg N/ha) best balanced DM yield, legume and forbs contribution and ME content.

Agronomy doi: 10.3390/agronomy16161537

Authors: Shaofei Wang Xiaozhe Ma Suisitong Zhou Yuhang Zhang Haobing Zhao Dayan Shang Chuanqi Shi Junnan Ding Lingbo Meng Shumin Li

Bio–tillage can continuously regulate the soil environment through plant roots and rhizosphere biological activities and is considered a low disturbance tillage practice that can alleviate soil compaction. However, long term chemical fertilization alone may limit rhizosphere carbon supply and weaken root–microbe interactions. Whether conservation management can coordinate root adaptation and arbuscular mycorrhizal fungal (AMF) responses to ameliorate the compacted soil environment and improve crop growth remains unclear. This study compared five treatments: chemical fertilizer alone (CN), straw return (SR), organic manure application (OM), straw return combined with organic manure application (SROM), and green manure intercropping (GM). SROM and GM showed the most pronounced soil amelioration effects. Compared with CN, SROM enhanced root tensile strength and elongation at break, increased the relative abundances of Glomus and Claroideoglomus and the accumulation of easily extractable and total glomalin–related soil protein (EE–GRSP and T–GRSP), reduced soil bulk density (BD) by 10.68% and 6.57% in the 0–20 and 20–40 cm soil layers, respectively, and increased MWD and GMD by 78.49–82.08%. The effects of GM were concentrated in the 20–40 cm soil layer, where enhanced soybean root Young’s modulus and complementary interspecific root distribution reduced BD by 7.36% and increased total porosity (TP) by 9.36%. GM also increased AMF root colonization, the relative abundance of Claroideoglomus, and soil nutrient availability. Additionally, SROM generally maintained the highest aboveground dry matter accumulation and exhibited the highest instantaneous growth rate, whereas the current–season growth benefit under GM was relatively limited. These findings highlight the key roles of roots and AMF in soil amelioration and soybean growth and provide a reference for optimizing low disturbance soil management in compacted black soil regions.

Agronomy doi: 10.3390/agronomy16161536

Authors: Jianjie Gao Xiaofeng Li Rihe Peng Bo Wang Wenhui Zhang Yongdong Deng Yu Wang Hongjuan Han Yongsheng Tian Cen Qian Lijuan Wang Zhenjun Li Quanhong Yao

Global warming-induced temperature increases adversely affect plant growth, exacerbating agricultural risks and threatening global food security. These challenges are particularly acute for important crops like non-heading Chinese cabbage (NHCC; Brassica campestris L. syn. B. rapa), a nutritionally and economically significant leafy vegetable cultivated worldwide. While breeding for thermotolerance has been explored to stabilize summer supplies, these efforts remain insufficient under complex field conditions, necessitating cost-effective and practical alternatives. Here, we demonstrate that biochar derived from enoki mushroom (Flammulina velutipes) spent mushroom substrate (SMS-BC) significantly alleviates heat-induced growth suppression in greenhouse-cultivated NHCC. SMS-BC alters the soil nutrient profile and enhances available phosphorus and potassium through its unique feedstock properties, including its filamentous architecture and surface functional groups. Furthermore, SMS-BC may reshape microbial community composition of NHCC under heat stress. Our findings establish SMS-derived biochar as an effective soil amendment for alleviating heat stress-induced growth suppression in NHCC.

Agronomy doi: 10.3390/agronomy16161535

Authors: Lucy Alvarado-Alva Santos Triunfo Leiva-Espinoza Daniel Iliquín Trigoso Manuel Oliva-Cruz

Cacao (Theobroma cacao L.) is a crop of great economic importance in Peru; however, the presence of cadmium (Cd) in cacao-growing soils limits its production and international trade. The objective of this study was to evaluate the effect of Solanum nigrum (black nightshade) and Bidens pilosa (cobbler’s pegs) on Cd removal in cacao-producing areas of northeastern Peru. The research was conducted using a completely randomized block design (CRBD) with two factors: the phytoremediation species and planting distance (30, 50, and 70 cm), in four production areas: La Concordia 01, La Concordia 02, La Lluhuana, and La Chorrera. The reduction in Cd in soil, roots, and cacao beans was evaluated, as well as the accumulation of the metal in leaves (30, 60, 120, and 150 days) and roots (120 and 150 days) of the phytoextracting species, in addition to the bioconcentration factor (BCF) and translocation factor (TF). Cd reductions were recorded in the soil, with a maximum decrease from 0.81 to 0.03 mg kg−1 (La Chorrera). In roots, the greatest reduction was from 1.79 to 0.69 mg kg−1 (La Concordia 02), while in beans it was from 1.65 to 1.08 mg kg−1 (La Chorrera). BCF values ranged from 1.12 to 6.97, with TF > 1, showing differences among the evaluated sites. Overall, the study findings demonstrate that the phytoextractive response was more related to site conditions than to the species used or the planting distance.

Agronomy doi: 10.3390/agronomy16161534

Authors: Ping-Yuan Yang Chun-Han Ko Bo-Xiang Lee Chihhao Fan Tang-Long Shen

Wastewater sludge can improve soil fertility and support resource recycling, but potential heavy metal accumulation limits its agricultural application. In this study, we evaluated the effects of anaerobically digested wastewater sludge, applied alone or in combination with the purple non-sulfur bacterium (Rhodopseudomonas palustris), on two green manure crops, Sesbania cannabina and Glycine max. A 90-day pot experiment was conducted with five treatments: control, sludge at 10 and 20 t/ha, and each sludge level combined with R. palustris. Soil physicochemical properties, plant biomass production, and heavy metal concentrations in soil and plant tissues were analyzed. Sludge application increased soil total carbon, total nitrogen, and available phosphorus, while co-application with R. palustris further enhanced phosphorus availability. The greatest biomass production response was observed in G. max under 20 t/ha sludge plus R. palustris, with a 78% increase after 90 days. However, heavy metal concentrations and plant uptake generally increased with sludge dosage, particularly for Ni and Cr. These results indicate that sludge–PNSB application may improve soil fertility and biomass production, but heavy metal risks require careful evaluation.

Agronomy doi: 10.3390/agronomy16161533

Authors: Huilin Yan Yifei Zhang Ruihong Zeng Xin Zhao Palinuer Aiwaili

Chrysanthemum morifolium is an important ornamental crop whose flowering is strictly regulated by photoperiod. However, the molecular mechanisms linking photoperiod signals to floral meristem identity and organ development in Asteraceae remain unclear. In this study, we identified and characterized CmAFL1, a FUL-like MADS-box gene specific to the Asteraceae family, in the short-day cultivar ‘Jinba’. CmAFL1 expression is upregulated under short-day conditions, primarily expressed in the shoot apical meristem during flower bud differentiation and predominantly in the receptacle during organ development. RNA interference-mediated silencing of CmAFL1 resulted in delayed flowering, arrested inflorescence development, malformed tubular florets, plant dwarfism, and excessive lateral branching, indicating its pleiotropic roles in flowering time, plant architecture, and floral organ patterning. At the molecular level, yeast one-hybrid assays revealed that the photoperiod pathway transcription factor CmCOL4 directly binds to the promoter region of CmAFL1. Furthermore, yeast one-hybrid and dual-luciferase assays confirmed that CmAFL1 directly interacts with and activates the promoter of the E-class floral organ identity gene CmSEP3. Together, our findings identify a novel transcriptional regulatory module CmCOL4-CmAFL1-CmSEP3 that potentially links photoperiod signaling to floral meristem identity and organ specification in Chrysanthemums. While further in planta validation is warranted, these findings provide novel insights into photoperiodic flowering regulation in Asteraceae and may serve as a theoretical foundation for molecular breeding strategies targeting flowering time manipulation in ornamental Chrysanthemums.

Agronomy doi: 10.3390/agronomy16161532

Authors: Peng Liu Yi-Hua Liu Jia-Rui Yang Xu-Qin Ren Lei Liu Ai-Sheng Xiong Guang-Long Wang

Fruit firmness is a pivotal agronomic and commercial trait that determines the storability, transport tolerance and edible quality of tomato (Solanum lycopersicum L.). Fruit softening severely restricts postharvest performance and economic benefits of tomato products worldwide. This review summarizes the latest research progress on factors and regulatory mechanisms governing tomato fruit firmness. Multiple environmental factors including temperature, light, moisture and atmospheric composition jointly affect cell wall structure and metabolism, thereby altering fruit firmness. Mineral nutrition, postharvest handling and pathogen infection also exert profound impacts on texture characteristics by modulating physiological activities and cell wall integrity. Phytohormones such as gibberellin, ethylene, abscisic acid, jasmonic acid and salicylic acid form complex signaling crosstalk to mediate fruit softening processes. Furthermore, we elaborate on the functions of transcription factors, quantitative trait loci, and key functional genes, as well as research advances in transcriptomics and metabolomics, including transcriptome analyses identifying differentially expressed genes related to cell wall remodeling, and metabolomic profiling revealing hydroxyproline and galacturonic acid as firmness-associated markers. Cell wall metabolism is confirmed as the core pathway controlling fruit softening. Finally, future research directions are proposed, focusing on single-cell and spatial transcriptomics to map softening regulatory networks, AI-driven predictive modeling for softening kinetics and shelf-life optimization, and CRISPR/Cas9-based gene editing for precise trait improvement.

Agronomy doi: 10.3390/agronomy16161531

Authors: Ning Yan Tong Mi Aihao Zhao Zonghuan Ye Zhihan Chen Yanan Song Chang Liu Ling Zhao He Zhang

This study investigated whether legume cover crops, particularly Vicia sativa L., improve soil fertility and fruit quality via microbial community remodeling, and whether this practice outperforms natural grass management in pear orchards. Five treatments were established: clean tillage (CK), natural grass (T1), Vicia sativa L. (T2), Vicia villosa Roth (T3), and a mixture of V. sativa and V. villosa (T4). High-throughput sequencing, soil biochemical assays, microbial co-occurrence network analysis, and PLS-PM were integrated to explore underlying mechanisms. Results showed that V. sativa significantly altered bacterial and fungal communities versus CK and T1, enriching beneficial taxa (Bradyrhizobium, Nitrospira, Mortierella, Tausonia) while suppressing pathogens (Alternaria, Fusarium, Curvularia). The V. sativa treatment also enhanced soil enzyme activities and nutrient availability, leading to increased fruit weight, soluble sugars, and ascorbic acid. PLS-PM revealed that legume treatments increased bacterial but decreased fungal abundance; bacterial communities positively correlated with soil nutrients and enzymes, whereas fungal communities showed negative correlations. Soil nutrients emerged as the primary factors associated with fruit quality improvement, with bacterial and fungal contrasting effects suggesting a potential microbial pathway. Collectively, V. sativa green manure optimized microbial structure by enriching beneficial microbes and suppressing pathogens, thereby improving soil health and pear fruit quality synergistically.

Agronomy doi: 10.3390/agronomy16161530

Authors: Yariv Ben Naim Yigal Cohen

Agrivoltaic (APV) systems enable the simultaneous production of food and renewable electricity. They create spatially heterogeneous environments that influence crop productivity. The quantitative relationships linking cumulative photosynthetically active radiation (PAR) with wheat productivity remain poorly studied. The objective of this study was to quantify the spatial distribution of cumulative PAR beneath a commercial single-axis tracking APV system and determine its relationship with wheat flowering, physiological responses, and grain yield. Wheat was cultivated across a 19-row transect between photovoltaic arrays at the Bar-Ilan University Agrivoltaic Research Farm, Israel. Cumulative PAR was measured separately for flowering (88 days after sowing, DAS) and physiological maturity (158 DAS). Physiological traits (plant height, SPAD chlorophyll index, and leaf nitrogen concentration), flowering, grain yield, and yield loss were quantified along the radiation gradient. Cumulative PAR varied among the 19 rows from 347 to 1917 mol m−2 at flowering and from 1570 to 4451 mol m−2 at maturity, while corresponding PAR losses ranged from 82.2% to 1.6% and 65.2% to 1.3%, respectively. Flowering increased from 33% in the most shaded row to 100% in the central rows and exhibited a strong quadratic relationship with cumulative PAR (R2 = 0.916; r = 0.913; p < 0.001). Plant height increased with increasing cumulative PAR, whereas SPAD and leaf nitrogen were greatest in the shaded edge rows, indicating physiological acclimation to reduced irradiance. Grain yield ranged from 2.96 to 6.04 t ha−1, corresponding to 46.2% yield loss to a 9.8% yield gain relative to the open-field reference. Grain yield was strongly associated with cumulative PAR (R2 = 0.811; r = 0.862; p < 0.001), while grain-yield loss closely followed PAR loss (R2 = 0.842; r = −0.883; p < 0.001). The results demonstrate that cumulative seasonal PAR is the principal environmental variable governing wheat development and productivity beneath tracking APV systems. The predictive equations developed here provide a practical framework for designing agrivoltaic systems that maximize crop productivity while maintaining efficient photovoltaic electricity generation.

Agronomy doi: 10.3390/agronomy16161529

Authors: Ulduza Ahmad Gurbanova Durna Rafael Aliyeva Atabey Agasoltan Jahangirov Turana Yashar Isgandarova Saida Tofig Zulfugarova Irada Mammad Huseynova

Water deficit is a major constraint on wheat productivity, and the reliable identification of drought-tolerant genotypes requires the integrated assessment of morphological, physiological, biochemical, and yield-related traits. Six winter bread wheat varieties and 15 advanced breeding lines grown under rainfed conditions at the Gobustan Experimental Station were comprehensively evaluated. Relative water content, soluble protein content, and the activities of aspartate aminotransferase, NADP-malic enzyme, phosphoenolpyruvate carboxylase, and NAD-malate dehydrogenase were determined. Heading time, plant height, and grain yield were also assessed. The lines Erytrospermum 100 and 21FAWWON9/Gaudio maintained relatively high flag-leaf water content and sustained metabolic enzyme activities at the later developmental stages, whereas 29th SAWYT N395 exhibited high activities of carbon-metabolism enzymes and favorable grain yield performance. Correlation analysis revealed a significant negative association between relative water content and phosphoenolpyruvate carboxylase activity, a positive relationship between NAD-malate dehydrogenase and phosphoenolpyruvate carboxylase activities, and a positive association between soluble protein content and grain yield. Overall, Erytrospermum 100, 21FAWWON9/Gaudio, and 29th SAWYT N395 were identified as promising breeding materials for improving drought adaptation and yield stability in rainfed wheat production systems.

Agronomy doi: 10.3390/agronomy16161528

Authors: Yanlong Zhang Fan Feng Changyuan Zhai Wei Zou Zhichong Wang Ping Jiang

To address the limitations of conventional point-based sampling methods (e.g., water-sensitive paper and filter paper) in characterizing the three-dimensional deposition distribution on curved fruit surfaces, this study proposed a fruit-surface deposition quantification approach validated through a coupled workflow comprising multi-view 3D reconstruction, target point cloud segmentation, and chemical wash-off quantification. A carmine solution was used as a tracer to simulate pesticide deposition. High-accuracy colored point clouds of apples were generated via multi-view 3D reconstruction, and the target deposition point cloud was automatically extracted using a combined strategy integrating K-means-based coarse color clustering with HSV threshold refinement. The target point cloud count was regressed against the measured single-fruit deposition volume. The results showed a significant linear relationship between the target point cloud count and deposition under both laboratory and real orchard air-assisted spraying conditions (laboratory: R2 = 0.827, r = 0.909, n = 13, p < 0.01; orchard: R2 = 0.885, r = 0.941, n = 17, p < 0.01). This method can characterize the differences in pesticide deposition among fruits while preserving the three-dimensional location information of the tracer-related region, thus providing a methodological basis for characterizing pesticide deposition on the fruit surface.

Agronomy doi: 10.3390/agronomy16161526

Authors: Haoquan Wang Rongqing Lu Chunjia Qi Xiaojun Wu Jiajia Liu Dazhong Zhang Junmei Hu Jie Song Xiangdong Chen Zhengang Ru

To address the core breeding demand for greater seedling vigor in bread wheat (Triticum aestivum L.) varieties adapted to the uniform sowing system in China’s Huang-Huai Wheat Region, we aimed to dissect the genetic architecture and identify core candidate genes for shoot length (SL) and root length (RL) at the germination stage. A natural population consisting of 204 wheat accessions was genotyped using the 660K SNP array, and a genome-wide association study (GWAS) integrated with transcriptomic, metabolomic, and proteomic analyses of extreme phenotypic accessions was performed. Both SL and RL were typical quantitative traits with an extremely significant positive correlation. A total of 111 and 176 significant SNPs were associated with SL and RL, respectively, including 56 shared loci. Glutathione metabolism was identified as the conserved core pathway for both tissues, while photosynthesis–antenna proteins and phenylpropanoid biosynthesis were identified as tissue-specific pathways in shoots and roots, respectively. Finally, we identified 7 core candidate genes for SL and 13 for RL, including three pleiotropic genes regulating both traits. This study provides valuable genetic resources and key targets for the molecular breeding of wheat varieties specialized for uniform sowing.

Agronomy doi: 10.3390/agronomy16161527

Authors: Xiang Dong Yichen Sun Zhenlei Zhang Zhengji Zhang Kangping Sun Fuzhen Zhou Ruohan Shi Weidong Jia

For the problem that, under the soybean-maize strip intercropping pattern, the installation of anti-drift shields changes the mass and inertia characteristics of the boom of a shielded sprayer, making it prone to severe vibration under complex field excitations and thereby affecting application uniformity and operational safety, a semi-active boom vibration damping system based on a magnetorheological damper was designed and tested. First, an equivalent mechanical model of the boom considering added mass and stiffness variation was established, and the characteristics of excitation sources such as road spectra and start-stop impacts were clarified. Second, based on the Bouc–Wen model, the magnetorheological damper was selected and its output force boundaries were designed. The stroke was determined to be 80–110 mm, and the maximum damping forces in the compression and rebound strokes were 1.15 kN and 3.44 kN, respectively. Furthermore, a semi-active vibration damping system with an LK3U-14MT PLC as the core controller was developed. Finally, simulation analysis, free-vibration decay tests, obstacle-crossing tests, and field operation tests were conducted to verify the vibration damping performance of the developed semi-active system. The field test results showed that, at typical operating speeds of 3–5 km/h, the semi-active vibration damping system reduced the maximum vertical amplitude at the boom tip by 28.6–43.1% and the maximum inclination angle by 12.2–55.6%, effectively improving the attitude stability and roll resistance of the boom of the shielded sprayer.

Agronomy doi: 10.3390/agronomy16161525

Authors: Wenxin Wei Ting Wen Xiaozhen Wang Liyi Wang Jiaen Zhang Benliang Zhao Dongwu Zhan

Animal activity plays an important role in regulating soil methane (CH4) and nitrous oxide (N2O) emissions. As a global invasive gastropod, golden apple snail (GAS, Pomacea canaliculata) has established great populations in wetlands, which has disturbed the soil ecological process. However, the impact of GAS activities on greenhouse gas (GHG) emissions is still unclear. A 25-day mesocosm experiment was conducted to examine CH4 and N2O fluxes, soil properties, microbial community, and GHG-related functional genes under low-density (GASL), high-density (GASH) and control (CK, without snail) treatments. Results showed that GASL significantly increased soil porosity and total nitrogen content by 18.6% and 7.6% on the 25th day. GASH significantly increased soil urease and sucrase activities by 18.1% and 30.0%. GASH significantly decreased the CH4 emission flux by 18.7% and increased the N2O emission flux by 33.1% on the 25th day. The 25-day cumulative CH4 and N2O emissions from female and male snail accounted for 0.002% and 2.3% of the total CH4 and N2O emissions in the GASH treatment, respectively. Moreover, GAS altered the soil microbial community composition. GASL significantly decreased the relative abundance of the phylum Chloroflexota by 11.3%, and increased the relative abundance of the family Nitrospiraceae by 24.5%. Compared with CK, GASH reduced the abundance of functional genes of mcrA, AOA-amoA, and nosZ by 16.9%, 19.7%, and 21.1%, respectively, while increasing the abundance of pmoA, AOB-amoA, and nirS by 18.4%, 65.3%, and 54.2%, respectively. These findings indicate that GAS disturbs soil physiochemical and microbial properties, and the conclusions are limited to a short-term mesocosm experiment.

Agronomy doi: 10.3390/agronomy16161524

Authors: Ailian Zhou Manfu Huang Zirui Wang Jiajia Liu Xiaohe Liang Qi Wang Shuo Xiao Jiayu Zhuang

Crop straw-to-grain ratio (SGR) estimation underpins regional straw resource assessment, yet national inventories rely on fixed coefficients that ignore structured variation across variety, environment, and phenotype. We introduce a Structured Multi-Kernel Heteroscedastic Gaussian Process (GP) framework that models SGR variation through three additive kernels heuristically motivated by the genotype–environment–phenotype (G+E+P) framework—capturing variety-associated variation, spatially structured variation, and environmental and management covariates—and employs an input-dependent noise model for prediction-specific uncertainty quantification. To prevent information leakage, target encoding and feature scaling are recomputed within each cross-validation fold. Evaluated via internal leave-one-out cross-validation on 80 rice samples (42 varieties, six Chinese provinces), the model achieves R2=0.541 with a prediction interval coverage probability of 0.95. Ablation identifies variety-associated variation as the largest contributor among the modeled factors (ΔR2=−0.024) and the multi-kernel design, by incorporating variety-specific information, substantially improves upon a covariate-only RBF GP (ΔR2=0.103). On point-prediction accuracy, Gradient Boosting achieves R2=0.58, slightly ahead of the Heteroscedastic GP (R2=0.54), underscoring that the primary advantage of the GP lies in its input-dependent uncertainty quantification. However, leave-one-county-out validation yields R2≈0 (with σ escalating to 24.4), confirming that the model does not yet generalize to unsampled counties; all reported performance is therefore internal to the nine sampled counties. The framework couples an agronomically motivated additive kernel structure with input-dependent uncertainty quantification, offering a path toward uncertainty-aware prediction from small field datasets.

Agronomy doi: 10.3390/agronomy16161523

Authors: Wenping Wang Peng Zhang Miaomiao Huang Zeliang Ju Hailong Zhang Kuiju Niu

The SWEET (Sugars Will Eventually be Exported Transporter) family, a class of sugar transporters identified in recent years, plays important roles in plant growth and development. Increasing evidence suggests that SWEET genes are also involved in plant responses to abiotic stresses, including salt stress. However, the genome-wide composition and salt-responsive functions of SWEET genes in Elymus nutans Griseb. have not been systematically characterized to date. This study presents the first genome-wide identification of the SWEET gene family in E. nutans and functional characterization of EnSWEET15 in salt stress response, providing candidate genes and a theoretical basis for improving salt tolerance in this species. A total of 12 EnSWEET genes were identified from the E. nutans genome and were unevenly distributed across eight chromosomes. Phylogenetic analysis classified them into four subfamilies, and promoter analysis revealed abundant cis-elements related to hormone signaling and stress responses, suggesting roles in abiotic stress adaptation. Expression analysis showed that EnSWEET15 was significantly upregulated in both roots and leaves under salt stress. The full-length EnSWEET15 coding sequence (930 bp ORF) was cloned and functionally characterized. Heterologous overexpression in Arabidopsis thaliana indicated that EnSWEET15 enhances salt tolerance. Transgenic lines showed reduced reactive oxygen species (ROS) accumulation and increased activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), compared with wild-type plants under salt stress. Overall, this study identifies EnSWEET15 as a positive regulator of salt tolerance via modulating ROS homeostasis, providing novel insights into SWEET-mediated salt stress response in perennial forages and valuable genetic resources for salt-tolerant breeding of E. nutans.

Agronomy doi: 10.3390/agronomy16161522

Authors: Wenya Zhang Jianping Zhou Yan Xu Xiaokang Chen Yuntian Gao Yulong Qiu

The xylem of cotton stalks is a high-quality biomass feedstock with strong high-value utilization potential. However, existing studies lack accurate calibration of discrete-element parameters for separated stalk components, which limits the optimization of the design of separation equipment. This study uses phloem, xylem, and pith of cotton stalks as research objects and measures the intrinsic physical and mechanical parameters and paired contact parameters of the three components. Given the strong agglomeration tendency of crushed phloem long fibers, the Hertz–Mindlin with JKR model is used to calibrate the adhesion parameter. The applicability of this model to low-moisture, high-aspect-ratio fibrous materials is verified, and the measured equivalent surface energy of phloem reaches 2.887 J/m2. CFD-DEM-coupled air separation verification is performed. The relative errors of xylem impurity content and loss rate between simulation and experiment are both below 10%, confirming the good reliability of the calibrated parameters. This study provides data to support the development of cleaning equipment for crushed cotton stalks. It provides a methodological reference for calibrating discrete-element parameters for similar long-fiber biomass materials.

Agronomy doi: 10.3390/agronomy16161521

Authors: Xin Zhang Zhongyi Liu Xingwang Wang Laiping Wang Haitao Su Hongwei Xu Shuai Lou Junwei Tan Zailin Huo

The maximum carboxylation rate (Vcmax) is a key parameter determining photosynthetic capacity in terrestrial biosphere models, yet its variability is often oversimplified as a plant functional type-dependent constant, increasing uncertainties in gross primary productivity (GPP) simulations. In this study, we inverted the daily Vcmax normalized to 25 °C (Vm25) by coupling the Breathing Earth System Simulator (BESS) model with the light response curves (LRC) method using eddy covariance observations at five maize sites in the United States and China. Then, four machine learning (ML) models—KNN, SVM, Random Forest (RF) and XGBoost—were employed to simulate Vm25, with RF showing the best performance (R2 = 0.83, RMSE = 7.57 μmol m−2s−1 for testing). Cross-validation further demonstrated the RF model’s ability to capture seasonal trends across sites. Incorporating the RF-simulated Vm25 into the BESS model significantly improved GPP estimates compared to the original BESS, with R2 increasing from 0.53–0.81 to 0.77–0.84. Through the SHAP method and ablation experiments, leaf age was identified as the most influential factor, with the largest SHAP value of 8.37 μmol m−2s−1, higher than that for temperature (4.47 μmol m−2s−1), solar radiation (4.21 μmol m−2s−1) and leaf area index (2.32 μmol m−2s−1). And vapor pressure deficit had the minimal SHAP value of 0.87 μmol m−2s−1. Notably, the effect of leaf age on Vm25 exhibited a unimodal pattern, with a strong coupling effect with leaf area index. This study demonstrates that interpretable machine learning not only provides a robust approach for simulating seasonally dynamic Vcmax, but also enhances our understanding of its driving biological and environmental factors, offering a valuable pathway for improving carbon cycle modeling in agroecosystems.

Agronomy doi: 10.3390/agronomy16161520

Authors: Jie Song Chenglin Peng Yang Chen Shujun Zhao Xiangyu Xu Hongwei Xu

Accurate prediction of plough layer thickness (PLT) in cropland is essential for soil quality assessment and sustainable land management, yet regional-scale PLT mapping remains challenging because PLT is a subsurface structural attribute that cannot be directly retrieved from surface spectral signals. This study developed an interpretable framework for province-scale mapping of cropland plough layer thickness (PLT) in Hubei Province, China, by integrating multi-source remote sensing observations, including Landsat 8 optical spectral bands, Sentinel-1 SAR backscatter, and crop dynamic spectral response metrics derived from multi-year Enhanced Vegetation Index (EVI) time series, together with topographic, climatic, soil physicochemical, and land-use variables. A total of 1926 cropland soil samples were used to train and validate random forest (RF), extreme gradient boosting (XGBoost), and Cubist models, while prediction uncertainty was quantified using 90% prediction intervals. The relative contributions of different environmental variable groups were assessed, and Shapley Additive Explanations (SHAP) were used to interpret key predictors. The all-variable scenario achieved the best overall performance, with RF showing the highest accuracy (R2 = 0.46; RMSE = 3.12 cm) and the narrowest prediction interval. Climatic and topographic factors dominated PLT spatial variability, whereas other variable groups provided complementary predictive information. These findings demonstrate the potential of integrating multi-source environmental data and interpretable machine learning for regional PLT mapping, and the mapped distribution of cropland PLT provides a spatial basis for cropland quality assessment and targeted soil management, although further improvements will require spatially explicit agricultural management information and more direct PLT-related predictors.

Agronomy doi: 10.3390/agronomy16161519

Authors: Fengwu Zhu Jinfeng Zhang Xinyu Li Wei Song Jingli Wang Lili Ren

The rapid and accurate prediction of soil organic carbon (SOC) content is of great significance for the study of carbon cycling and the evaluation of soil fertility. Nowadays, with the development of spectroscopy and intelligent technologies, related technologies have been widely used in the prediction of soil elements due to their advantages of low cost, non-destructiveness, real-time performance, and rapid determination. In this article, the advantages of visible-near-infrared (VNIR) and hyperspectral imaging (HSI) spectral technologies are first described. Feature extraction and multi-feature fusion methods based on spectral data are analyzed, the role of multi-feature fusion in improving prediction accuracy is emphasized, and the establishment of efficient and reliable prediction models is discussed. Subsequently, multi-feature fusion methods for spectral data are explored, and it is pointed out that single feature extraction methods have limitations, requiring the combination of deep learning and manual feature extraction methods. In terms of modeling methods, the foundation of SOC prediction is introduced, especially the research on the prediction of soil profile organic carbon based on VNIR and HSI, as well as the application of multimodal models in agriculture. The important role of the combination of multimodal models and large language models in improving the level of intelligent agricultural production is highlighted. Therefore, the application of multimodal models in agriculture is summarized. LLMs may serve as knowledge-integration and decision-support interfaces that help interpret SOC prediction outputs, integrate agronomic knowledge, and convey information to the end users.

Agronomy doi: 10.3390/agronomy16161518

Authors: Farjana Rauf Tran Thi Thu Hien Nguyen Thi Thu Thuy Asami Tomita Yoshihiko Hirai

Soil salinity is a major constraint limiting rice productivity, particularly at the reproductive stage. To elucidate the genetic basis of reproductive stage salinity tolerance, this study validated and fine-mapped quantitative trait loci (QTL) for yield-related traits using a salinity-tolerant line SL506, identified through screening of Nona Bokra–CSSLs in a Koshihikari background. In 2016, the F2 population derived from SL506/Koshihikari was evaluated under long-term salt stress; three QTLs associated with plant dry weight, panicle number, and grain weight were detected on chromosome 2. In 2023, validation analysis using F3 individuals confirmed the presence of these QTLs. Subsequent fine-mapping using F4 near-isogenic lines (NILs) delimited the QTL to a 1.7 Mb interval and high-resolution mapping using an F5 recombinant population progressively refined it to a 473 kb genomic region containing 69 annotated genes. Variant Effect Predictor analysis identified 15 deleterious nonsynonymous variants (SIFT < 0.05) in six candidate genes. Based on annotated gene functions, predicted variant effects, and their membership in stress-related gene families, OsPP2C24, OsFbox102, and OsWAK14 were suggested as the most promising candidate genes underlying qPDW2. These findings provide insights into the genetic basis of reproductive-stage salinity tolerance from valuable resources for the future improvement of salt tolerance and yield stability in rice.

Agronomy doi: 10.3390/agronomy16161517

Authors: Kongzhong Xiao Hui Li Hang Huang Feifan Shuai Siyu Liu

Interspecific hybridization is a key strategy for germplasm innovation in lilies (Lilium spp., Liliaceae). However, successful hybridization between aneuploid female and aneuploid male gametes has not been reported in this genus. We used two triploid female parents—autotriploid (AAA) and allotriploid (LAA)—crossed with an odd-allotetraploid (LAAA) male that produces functional aneuploid pollen—to explore the effects of maternal genotype on chromosome introgression. Genomic in situ hybridization (GISH) analysis was performed on mitotic metaphase chromosomes of the progeny to determine chromosome number and genome composition. Both crosses were successful, confirming aneuploid female × aneuploid male compatibility. The AAA × LAAA progeny had concentrated chromosome numbers (40–45), averaging 2.33 Longiflorum (L) chromosomes, with L and L/A recombinants accounting for 6.67–20%. In contrast, the LAA × LAAA progeny showed wider variation (38–61), averaging 10.67 L chromosomes, with L and L/A proportions of 25.00–39.53%. Therefore, the maternal genotype decisively affects introgression: LAA (containing the L genome) promotes high-proportion alien introgression, whereas AAA (lacking L) favors low-proportion introgression. This is the first report on maternal regulation in aneuploid × aneuploid crosses, providing a theoretical basis for targeted parental selection in lily germplasm introgression breeding.

Agronomy doi: 10.3390/agronomy16161516

Authors: Zixuan Zhang Huawei Yang Peng Qi Xiaojie Shi Xinbing Ding Shaowei Wang Shucheng Wang Lu Xun Supakorn Wongsuk Liyang Su

Swarm control technology, leveraging artificial intelligence algorithms to coordinate multiple devices, offers an effective solution for developing precision and intelligent operation systems in orchard management. This paper focuses on the core technologies underpinning swarm coordination and reviews the current state of research on collaborative communication, path planning, task allocation, and formation control, with reference to both domestic and international studies. Based on the full growth cycle of fruit trees, encompassing monitoring, precision management, and harvesting, the paper summarizes the applications and research progress of swarm control technology at each stage. Furthermore, it identifies key challenges in applying swarm technology to orchard environments, including low efficiency in heterogeneous system coordination, delayed responses to dynamic conditions, resource constraints in large-scale swarm systems, and limited adaptability to agricultural contexts, and offers strategic recommendations to address these limitations.

Agronomy doi: 10.3390/agronomy16161514

Authors: Anand Kumar Emmanuel C. Omondi Dilip Nandwani Mitchell D. Richmond Rodgers Kabenomuhangi Sai Suvidh Maddela

Floral hemp production requires agronomic practices that maximize biomass and cannabidiol (CBD) yield while maintaining legal tetrahydrocannabinol (THC) limits. A two-year field study was conducted at the Tennessee State University Agricultural Research and Education Center to evaluate floral hemp (Cannabis sativa L.) production under a Non-Chemical System (NCS) and Chemical System (CS) at a uniform nitrogen (N) rate of 100 kg ha−1. Four cultivars (‘Fukuoka’, ‘Rushmore’, ‘Cherry’, and ‘Virginia’), two mulch types (plastic and straw), and two propagation methods (seed and clone) were evaluated for effects on biomass yield, plant height, CBD and THC concentrations, and the Compliance Regulatory Index (CRI). The production system did not significantly affect biomass; however, plant height and CBD and THC concentrations were significantly influenced. Across cultivars, mulched plants under CS were taller than those under NCS. Seed-propagated ‘Fukuoka’ under NCS and ‘Virginia’ under CS produced the highest THC concentration. ‘Rushmore’ exhibited greater consistency across production systems and propagation methods. In 2023, plastic mulch increased biomass by 38% compared with no mulch, while in 2024, straw mulch increased biomass by 154%. CRI varied significantly among cultivars and was influenced by year and propagation method. ‘Cherry’ clones and seed-propagated ‘Fukuoka’ showed greater CBD potential at the 0.3% THC threshold in 2023. Although CS with seed propagation showed a slight agronomic advantage, NCS demonstrated comparable performance. Significant performance declines in the second year suggest that continuous monocropping of floral hemp may compromise long-term productivity. A supplementary 2022 harvest-timing study demonstrated cultivar-dependent differences in cannabinoid accumulation and THC compliance during floral maturation.

Agronomy doi: 10.3390/agronomy16161515

Authors: Jie Bai Tuo Yao Wenbo Xu Yang Lei Chen Zhang Jiali Chai

Salt stress is a prevalent abiotic stress worldwide, which markedly inhibits crop growth and triggers yield losses. In this study, salt-tolerant plant-growth-promoting rhizobacteria of Cerasus humilis—Bacillus pumilus and B. velezensis, which possess nitrogen-fixing, phosphate-solubilizing, and indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase-producing traits—were co-inoculated with Sinorhizobium meliloti. The effects of these bacterial combinations on alfalfa (Medicago sativa L.) were systematically evaluated during seed germination and plant growth under salt stress simulated using NaCl, Na2SO4, NaHCO3, and Na2CO3 at varying intensities. The results showed that under salt stress, inoculation significantly increased the seed germination rate by 11.33–41.33%. Pot experiments further revealed that inoculation significantly enhanced symbiotic nitrogen fixation efficiency in alfalfa and effectively maintained K+/Na+ homeostasis (K+ concentration increased by 4.23–125.34%, while Na+ concentration decreased by 7.15–102.09%). Concurrently, inoculation upregulated antioxidant enzyme activities and promoted the accumulation of non-enzymatic antioxidants, thereby significantly reducing reactive oxygen species levels. Moreover, inoculation substantially increased the content of osmoregulatory substances such as proline and soluble protein; proline accumulation surged more than fivefold (39.97–551.05%) compared with the non-inoculated control, effectively alleviating cellular dehydration. Through these multi-pathway regulations mediated by Bacillus sp. and S. meliloti, the inhibitory effect of salt stress on alfalfa growth was significantly mitigated, with dry weight increasing by 45.9–92.4%. Principal component analysis indicated that inoculation with the B. velezensis–S. meliloti microbial combination was the most promising strategy for promoting alfalfa growth and alleviating salt stress. The results provide a theoretical basis for developing microbial fertilizers and establishing alfalfa pastures in saline lands, thereby promoting their sustainable utilization.

Agronomy doi: 10.3390/agronomy16151513

Authors: Xinping Li Han Zhang Jiarui Hou Fuli Ma Jing Pang Lingxin Geng Hongjian Wu Jialiang Zhang

Maize kernel damage detection is critical for grain quality assessment and post-harvest processing. However, existing deep learning methods struggle to balance accuracy, model complexity, and multi-class recognition under real-world conditions. To address these issues, this paper proposes YOLOv11n_DEG, an improved lightweight detection model based on YOLOv11n. The model uses the first ten pretrained layers as a feature extractor, replaces standard convolutions in the backbone with depthwise separable convolutions to reduce parameters, integrates an Efficient Channel Attention (ECA) module to enhance feature representation, and employs a dual-dropout strategy in the classification head to mitigate overfitting and improve generalization. Additionally, to account for potential discrepancies in damage characteristics between the obverse and reverse sides of maize kernels, a dual-sided synchronous image feature fusion method is introduced. The output layer classifies five target categories for multi-class damage detection. On an independent test set, the proposed model achieves a precision of 92.5%, a recall of 89.6%, and a mean average precision (mAP) of 93.4%, outperforming the original YOLOv11n by 6.2%, 4.0%, and 3.7%, respectively, while reducing parameter count and computational complexity by 32.9% and 6.5%. To validate practical deployability, a custom testbed with dual-camera synchronous acquisition and geometry-based matching was developed. On this platform, the model with dual-sided fusion achieves a single-side recognition accuracy of 94.1% and a dual-sided recognition accuracy of 89.3%, with an average detection time of 0.8 s per batch. These results demonstrate that YOLOv11n_DEG provides an accurate and practical solution for intelligent maize kernel damage detection, with strong potential for real-world deployment in grain inspection systems.

Agronomy doi: 10.3390/agronomy16151512

Authors: Yiwei Yan Rui Han Jie Tian

Fructan metabolism governs garlic bulb expansion and yield formation. Dynamic carbohydrates and four fructan-metabolizing enzymes (1-FFT, 1-SST, 1-FEH, INV) of ‘Ledu purple garlic’ were tracked over 0–84 days after transplanting. Combined with multivariate statistics and carbon contribution quantification, we analyzed source–sink carbohydrate allocation. Garlic growth was divided into three phases: 0–42 d leaf vegetative growth, 42–56 d synchronous leaf and bulb development, and 56–84 d rapid bulb bulking. Fructan was the dominant storage carbohydrate in bulbs, peaking at 869.81 mg·g−1 DW at harvest. Aerial carbohydrates were degraded and remobilized underground in late growth, while bulb monosaccharides showed bimodal fluctuations. Carbon supply shifted sequentially: mother bulbs supplied carbon at the seedling stage, leaves and pseudostems co-provided photosynthates in the mid-term, and pseudostems became the major temporary remobilizable carbon storage organ during late bulking under this single-site trial with a 14-day sampling interval. Fructan contents and enzyme activities exhibited obvious stage-specific patterns and could act as potential biochemical markers for distinguishing growth stages of ‘Ledu purple garlic’ under the present single-site field trial; their broad applicability across diverse garlic cultivars remains to be verified. 1-FFT was active only in early stages, while bulb 1-SST increased continuously. Day 42 represented the source–sink transition threshold with peak INV activity. Synchronous variation in enzyme activities only hints at coordinated carbohydrate redistribution under this test environment, which may support bulb dry matter accumulation.

Agronomy doi: 10.3390/agronomy16151511

Authors: Xiang Li Qianbing Zhang

Arbuscular mycorrhizal fungi (AMF) and rhizobia establish mutualistic symbioses with plant roots. This study focused on their effects on alfalfa (Medicago sativa L.) growth, root morphology, nutritional quality, photosynthetic characteristics, and protein fractions; eight treatments were established: single inoculation with three AMF strains (Funneliformis mosseae, Claroideoglomus etunicatum, Glomus versiforme) or Sinorhizobium meliloti (Sm), dual co-inoculation of each AMF with Sm, and a non-inoculated control (CK). Results showed that all AMF successfully colonized alfalfa roots, with co-inoculation increasing both mycorrhizal colonization rate and nodule number. The F. mosseae × Sm treatment achieved the highest colonization (83.3%) and nodule count (76 per plant). Across two years, this treatment significantly increased aboveground biomass, plant height, and stem diameter (p < 0.05). C. etunicatum × Sm significantly reduced acid detergent fiber content, while dual inoculation markedly improved net photosynthetic rate and light-use efficiency. All inoculations increased rapidly (PB1) and intermediate-degradable protein (PB2) but decreased non-protein nitrogen (PA) and bound protein (PC). In conclusion, AMF and rhizobia exhibit significant synergistic effects. Co-inoculation (F. mosseae × Sm and C. etunicatum × Sm) enhances alfalfa productivity by optimizing root structure, improving photosynthesis, and regulating nitrogen metabolism.

Agronomy doi: 10.3390/agronomy16151510

Authors: Xia Yang Liwen Mai Tianjing Lian Dingmei Wang Jiacong Lin Ning Wang He Liu

Bioconversion of chicken manure by Hermetia illucens (black soldier fly, BSF) larvae offers a sustainable route for organic waste disposal and protein production, yet how carbon source bioavailability regulates this process remains unclear. We conducted 13-day trials on chicken manure across 27 combinations of three supplement-to-manure mixing ratios (SMMRs, 3:1, 1:1, and 1:3, dry weight basis) and nine carbon blends (sawdust, straw, and corn flour). Measured endpoints included larval yield, substrate temperature dynamics, GHG emissions, global warming potential (GWP), ammonia volatilization, carbon–nitrogen fixation, and frass characteristics. Carbon source identity showed a much stronger association with performance than did the manure-to-supplement mixing ratio. Dry-basis larval yield ranged from 3.5% to 13.2% (mean 7.4%), total GWP ranged from 5105.6 to 8737.2 mg kg−1, and ammonia emissions from 419.6 to 1114.1 mg kg−1. Optimal larval yield was combined with a 3:1 SMMR with corn-flour-rich blends, which boosted productivity and C-N retention. Labile carbon was associated with enhanced lipogenesis, amino acid accumulation, C-N sequestration, and reduced GHG emissions. In contrast, recalcitrant carbon (sawdust) restricted degradation, intensified microbial competition, and induced energy shortage and nutrient losses, impairing conversion efficiency. These findings are consistent with carbon bioavailability rather than C/N, being a key correlate of BSF performance through energy–microbe–substrate interactions. We further propose that substrate formulation targeting labile carbon enrichment can serve as a practical strategy to simultaneously improve larval production and mitigate environmental impacts, though the inferred mechanisms await direct microbiological validation.

Agronomy doi: 10.3390/agronomy16151509

Authors: Chuanjia Xu Xiaoyu Wang Hao Zhan Changfu Li Yansheng Zhang

Trigonelline is a bioactive pyridine alkaloid in Trigonella foenum-graecum, which is a legume species, and is known for its hypoglycemic and hypolipidemic activities. Phytosulfokine-δ (PSK-δ), a recently identified legume-specific phytosulfokine peptide, has been implicated in the regulation of nodulation and root development. However, whether PSK-δ participates in the regulation of secondary metabolite biosynthesis remains unclear. In this study, exogenous PSK-δ treatment significantly promoted trigonelline accumulation in T. foenum-graecum seedlings, leading to a 93% increase in trigonelline content after 5 days relative to the scrambled-pentapeptide-treated control, whereas a slight downward trend was observed at 15 days. Comparative transcriptomic analyses between PSK-δ-treated seedlings and the corresponding controls at 5 and 15 days identified 15 candidate genes associated with trigonelline biosynthesis and PSK signaling, whose expression patterns were consistent with trigonelline accumulation dynamics. Co-expression network analysis between these 15 candidate genes and 831 transcription factor-encoding genes identified candidate transcription factors potentially involved in the coordinated regulation of trigonelline biosynthesis and PSK signaling. These findings suggest that PSK-δ may serve as a potential peptide-based biostimulant for regulating alkaloid accumulation in medicinal legume cultivation and provide insights into peptide hormone-mediated regulation of plant metabolism.

Agronomy doi: 10.3390/agronomy16151508

Authors: Ning Ma Shiqi Xi Kunyu Li Siyu Wang Mengjing Ni Zijun Zhou Shirong Zhang Xiaojing Liu Yongxia Jia Yulin Pu Lan Li Xiaoxun Xu Guiyin Wang Ting Li

In this study, bacterial α-diversity, represented by Chao1 richness and Shannon diversity, was quantified and mapped across the acidic red and yellow soils of southern China by integrating a comprehensive meta-database of 920 georeferenced observations with multi-source environmental data and machine-learning models. Chao1 and Shannon were modeled using Random Forest, eXtreme Gradient Boosting, and Support Vector Machine algorithms. Among these, Random Forest consistently achieved the highest predictive accuracy and robustness (R2 > 0.83). SHapley Additive exPlanations (SHAP) analysis revealed that soil pH acted as the fundamental filter for both diversity dimensions, while they were further shaped by distinct environmental controls. The Normalized Difference Vegetation Index (NDVI) negatively constrained species richness, reflecting the prevalence of intensively managed monoculture systems in this region, whereas temperature exerted a strong negative control on community evenness. Spatial predictions showed pronounced regional contrasts among the Southwest, Middle–Lower Yangtze, and Southern China agricultural zones, with uncertainty patterns closely linked to terrain complexity and data density. The results demonstrate that bacterial richness and evenness respond to distinct yet interacting environmental controls, highlighting the necessity of multidimensional diversity assessment. This study provides a scalable and interpretable framework for digital soil mapping of microbial diversity, offering spatially explicit insights for managing acid-sensitive agroecosystems under environmental change.

Agronomy doi: 10.3390/agronomy16151506

Authors: Adriano Francis Dorigan Edson Ampélio Pozza Rafael Lemos Alves Patricia Ricardino da Silveira Gabriella Alves Ramos Indiara Carol Lopes Pinheiro Eduardo Alves

Pyricularia oryzae Triticum lineage (PoTl), the fungal pathogen responsible for wheat blast disease, has demonstrated increased fitness, stable resistance to quinone outside inhibitor (QoI) fungicides, and no associated fitness cost in the absence of fungicide selection pressure. In this study, we assessed whether the fitness-related epidemiological traits and competitive abilities of QoI-resistant (R) PoTl isolates increased or remained unchanged under continuous QoI applications across multiple disease infection cycles in wheat plants, compared to untreated plants. Approximately 48 h before inoculating each group of QoI-R or sensitive (S) PoTl isolates, wheat plants were treated with 10 μg mL−1 azoxystrobin. The EC50, incubation and latent periods, as well as the germination capacity of the QoI-R isolates inoculated on wheat leaves treated with 10 μg mL−1 azoxystrobin, remained unchanged throughout five successive infection cycles. However, continuous azoxystrobin applications throughout successive disease cycles increased head blast severity by 1.33-fold and conidial production on wheat leaves by 36.8-fold in QoI-resistant (QoI-R) PoTl isolates compared with untreated plants. Conidia germination and germ tube development by QoI-R isolates on the abaxial surface of wheat leaves and/or head rachis treated with 10 μg mL−1 azoxystrobin, six hours after inoculation (h.a.i), were observed using a scanning electron microscope (SEM). These findings demonstrate that repeated azoxystrobin exposure enhances fitness-related epidemiological traits of QoI-R PoTl isolates. Consequently, alternative evolutionarily informed disease management strategies, including fungicide rotation, multisite fungicides, and integrated disease management, are urgently needed.

Agronomy doi: 10.3390/agronomy16151507

Authors: Xiangyu Liang Yujie Zhao Jianjun Ma Hong Li Tiantian Ma Junhua Ma Xiang Yue Cheng Ma

To characterize heavy metal accumulation, potential sources, and source-specific ecological risks in farmland soils of the Ningxia Yellow River Irrigation Area, 537 topsoil samples were analyzed for As, Hg, Cd, Pb, and Cr. positive matrix factorization (PMF) was coupled with the potential ecological risk index to quantify source-specific mass and ecological risk contributions. Cd and Hg showed the strongest enrichment relative to regional background values, with mean concentrations of 2.38 and 2.02 times the respective background values. PMF resolved four factors interpreted as an agricultural input-related source, a parent material-dominated natural source, an urban industrial- and combustion-related atmospheric deposition source, and a Yellow River alluvial–hydrological natural background source. The mean potential ecological risk index calculated from PMF reconstructed concentrations was 168.45, closely matching the observed value of 168.77. Source-specific mass and ecological risk contributions were clearly decoupled: the two natural source factors contributed 71.19% of the modeled heavy metal mass but only 24.21% of the ecological risk, whereas the two anthropogenic source factors contributed 28.81% of the mass but 75.80% of the risk. The atmospheric deposition and agricultural input-related sources contributed 47.27% and 28.53% of the ecological risk, respectively. Site-level bootstrap resampling and alternative allocation procedures retained the source risk ranking. These findings indicate that risk-based management should prioritize Hg-related atmospheric deposition and Cd-related agricultural inputs rather than total heavy metal mass alone.

Agronomy doi: 10.3390/agronomy16151505

Authors: Ruomin Wu Zhiying Zhou Jiayang Li Huabin Xie Jiafeng Wang Chun Chen

Rice blast and bacterial blight are two major diseases that threaten rice production worldwide. Developing rice cultivars with both disease resistance and desirable grain quality is an important objective in modern rice breeding. In this study, R1179 carrying Pi2, Wxb and Alkb was crossed with IRBB7 carrying Xa7, Wxb and Alkb. Marker-assisted selection (MAS) was applied to an F2 population of 1123 plants, and a line, G163, combining Pi2, Xa7, Wxb and Alkb, was developed. Disease resistance evaluation showed that G163 retained the blast resistance conferred by Pi2 and the bacterial blight resistance conferred by Xa7, exhibiting resistance to the tested isolates of both pathogens. Grain quality assessment indicated that G163 possessed favorable milling, appearance and eating quality traits. Rapid Visco Analyzer (RVA) profiling further indicated desirable starch pasting properties. In conclusion, the rice line G163 carrying Pi2, Xa7, Wxb and Alkb was successfully developed through MAS. The results provide a useful germplasm resource for breeding rice cultivars with combined disease resistance and desirable grain quality.

Agronomy doi: 10.3390/agronomy16151504

Authors: Yan Zhou Feiyang Xia Jun Lu Xiang Wang Junwen Qi Qijie Jin Shengtian Zhang Jiansheng Li

Humic substances (HSs) possess abundant oxygen-containing functional groups that theoretically confer exceptional complexation capacity for heavy metal (HM) remediation; however, their speciation-dependent extractive behaviors across multi-metal contaminated soils remain insufficiently quantified. This study systematically evaluated the washing performance of six humic-based agents derived from weathered coal and lignite on soils contaminated with representative cadmium and arsenic species. Batch sequential washing experiments demonstrated that a four-cycle extraction at a liquid-to-solid ratio of 30:1 achieved high average cumulative removal efficiencies of 92.9% for Cd and 83.0% for As, with weathered coal-derived humic acid (HAW) exhibiting the highest removal efficiency. Microstructural and spectroscopic characterizations indicated that abundant oxygen-containing functional groups and highly condensed aromatic structures served as the core drivers for HM complexation. Furthermore, the XGBoost-SHAP model accurately predicted Cd leaching efficiency, identifying washing times as the most influential variable, followed by contaminant speciation, leaching agent type, and L/S ratio. The substantially lower performance for As suggests that arsenic leaching is governed by additional physicochemical factors beyond the four operational variables, highlighting the need for speciation-related descriptors in future modeling efforts. Overall, this work demonstrates the technical feasibility of converting low-rank coal resources into high-value, sustainable soil washing agents, offering robust data-driven insights for the targeted design of site remediation strategies.

Agronomy doi: 10.3390/agronomy16151503

Authors: Zhongqiu Fu Xiangkun Meng Wantong Zhao Xu Wu Chang Ma Shibo Du Xinrui Bai Yongguang Li Xue Zhao Yingpeng Han Yuhe Wang

Fusarium root rot, primarily caused by Fusarium solani, is a damaging soil-borne disease that restricts soybean growth and reduces yield. In the present study, a panel of 330 soybean germplasm accessions was inoculated with F. solani. Disease responses were evaluated using the disease severity index (DSI). The soybean accessions displayed substantial variation in their susceptibility to F. solani. Based on DSI, 39 accessions were classified as highly resistant, 94 as resistant, 125 as susceptible, and 72 as highly susceptible, accounting for 11.82%, 28.48%, 37.88%, and 21.82% of the panel, respectively. The genome-wide association study (GWAS) was performed using a genotyping dataset of 627,436 high-quality single nucleotide polymorphisms (SNPs) and two models, Fixed and random model Circulating Probability Unification (FarmCPU) and mixed linear model (MLM). Both GWAS models detected putative SNP associations across seven chromosomes. Based on SNP allelic-effect analysis and gene function annotation, eight genes were prioritized and subsequently evaluated by quantitative reverse transcription PCR (qRT-PCR) for their responses to F. solani infection. Two Kompetitive allele-specific PCR (KASP) markers, KASP-S13_37431242 and KASP-S13_37529208, were developed from resistance-associated SNPs on chromosome 13 and evaluated across the diverse soybean association panel used in this study. Accessions carrying the favorable genotypes of these markers were enriched for resistant germplasm, with positive predictive values of 65.52% and 66.67%, respectively, indicating their potential value for preliminary favorable-allele tracking and germplasm prioritization. Collectively, these results improve our understanding of the genomic components underlying soybean responses to F. solani. The identified loci, candidate genes, and KASP assays provide a basis for further functional validation and the development of multi-locus strategies for improving soybean resistance to Fusarium root rot.

Agronomy doi: 10.3390/agronomy16151502

Authors: Aishajiang Aili Hailiang Xu Abdul Waheed Fabiola Bakayisire Yongqiang Yang

Water scarcity strongly constrains the revegetation of disturbed mine substrates in cold-arid regions. This study compared soil-moisture dynamics between a microtopographic reclamation area and an adjacent flat reclamation area in an abandoned stone quarry within the Kalamaili Ungulate Nature Reserve, northwestern China. The integrated restoration treatment, established in 2018, combined linear trenches 30–40 cm deep and spaced 60 cm apart, native seed sowing, transferred seed-bank topsoil, and water-retaining material. From January to December 2024, sensor-derived apparent volumetric water content was monitored at five depths—0–10, 10–20, 20–30, 30–40, and 40–50 cm—at 10 min intervals using sensors operated with the manufacturer’s standard calibration. Following quality control and temporal synchronization, 41,475 valid timestamps were retained for each monitored profile. The study provides a continuous full-year, multi-depth record from an unirrigated, cold-arid reconstructed quarry substrate, a setting that remains underrepresented in previous micro-catchment and dryland-restoration research. However, this study is based on a single hydrological year and does not directly measure plant physiological responses or long-term restoration outcomes. Therefore, elevated soil moisture should be interpreted as a preliminary indicator of restoration potential rather than a definitive measure of ecological recovery success. The monitored microtopographic profile maintained higher mean apparent water content than the flat profile during most of the year. The largest annual relative profile difference occurred at 10–20 cm depth, reaching 18.0%, followed by 11.7% at 0–10 cm, whereas differences decreased below 20 cm and reached 1.9% at 40–50 cm. During selected rainfall and probable snowmelt periods, the microtopographic profile exhibited larger wetting responses and slower post-event recession. These patterns indicate contrasting upper-profile wetting and drying dynamics between the two monitored reclamation configurations. However, runoff, infiltration, evaporation, snow accumulation, soil-water potential, and vegetation responses were not measured directly. Moreover, monitoring began several years after vegetation establishment, and trenching, seed addition, seed-bank transfer, and water-retaining material were not evaluated independently. The findings should therefore be interpreted as a site-specific post-establishment comparison rather than evidence of the isolated effect of microtopography. Replicated, multi-year studies are required to determine the mechanisms, effectiveness, and broader transferability of this integrated reclamation configuration.

Agronomy doi: 10.3390/agronomy16151501

Authors: Juan Zapata-Londoño Juan Botero-Valencia Vanessa García-Pineda Erick Reyes-Vera Ruber Hernández-García

References [...]

Agronomy doi: 10.3390/agronomy16151500

Authors: Yanan Zhao Qingchao Zeng Kunzhi Long Qian Zhou Chengrui Huang Ziyi Liu Shuai Yuan Lixia Zhang Zhenshuo Wang Yan Li Wei Shi Qi Wang

The soil-borne oomycete pathogen Phytophthora capsici poses a serious threat to plant growth and results in substantial economic impact on the pepper industry. Therefore, the isolation of multifunctional biocontrol agents has become a major research priority. In this study, we isolated a biocontrol strain, Bacillus subtilis Z-294, which demonstrated strong inhibition of P. capsici in both plate and greenhouse experiments. This strain Z-294 exhibited broad-spectrum antagonistic activities as well as plant growth-promoting ability. Phylogenetic analysis based on core-genome and average nucleotide identity (ANI) further identified Z-294 as B. subtilis. Importantly, we found that the strain Z-294 alleviates the P. capsici disease through mechanisms associated with changes in the plant microbiome. Plants treated with Z-294 showed higher alpha-diversity. The application of B. subtilis Z-294 showed that the relative abundance of Alphaproteobacteria, Bacilli, Bacteroidia, Agaricomycetes, and Eurotiomycetes increased, while the relative abundance of Gammaproteobacteria and Sordariomycetes declined. Strain Z-294 holds great promise as a multifunctional biocontrol agent for the sustainable management of diseases and the enhancement of plant health, laying a solid foundation for its future agricultural applications.

Agronomy doi: 10.3390/agronomy16151499

Authors: Xiaopeng Sun Yifei Li Pei Zhang Haitao Jia Feng Teng Shilong Zhang Wenqiang Li Zhenghua He

The NSUN family is essential for RNA 5-methylcytosine modification (m5C) in eukar-yotes. However, no NSUN genes have been identified in maize, and the characteristics of ZmNSUN genes remain unexplored. Here, we performed a comprehensive in-vestigation of NSUN genes across seven Poaceae species. Our analysis identified a total of 63 Poaceae NSUN genes, including eight ZmNSUN genes in maize. Phylogenetic and feature analyses classified the Poaceae NSUNs into six subgroups (SGs), suggest-ing that the divergence of these SGs may have occurred prior to the divergence between plants and animals. Expression profiling indicated that ZmNSUN genes are generally repressed by heat stress. Co-expression network analysis suggested potential roles of ZmNSUN genes in maize development, and expression quantitative trait locus (eQTL) analysis results demonstrated that expression levels of multiple ZmNSUN genes are significantly associated with maize agronomic traits. Collectively, these findings provide novel insights into the evolutionary dynamics of the NSUN family and highlight specific ZmNSUN genes as promising candidates for molecular breeding to improve maize yield and stress adaptability.

Agronomy doi: 10.3390/agronomy16151498

Authors: Fangfang Fan Xiaoqiang Cheng Yao Wang Jirong Wu Ruizhen Liu Yubin Wang Lan Ju Haisheng Yan Hao Niu Xin Lv Jianqiang Chu Junai Ping

Sorghum (Sorghum bicolor (L.) Moench) is an important crop with remarkable tolerance to adverse environments, including nitrogen deficiency. To investigate the mechanisms underlying sorghum tolerance to low-nitrogen (LN) stress, we integrated phenotypic evaluation, transcriptome profiling, weighted gene co-expression network analysis (WGCNA), and haplotype analysis. Two accessions, the LN-tolerant ‘Liaonian B-1’ and the LN-sensitive ‘Yikeerli’, were examined under hydroponic and field conditions. Under LN conditions, Liaonian B-1 showed increases of 32% in root length, 4.3-fold in root fresh weight, and 91% in root dry weight, whereas the LN-sensitive accession showed severe reductions in shoot biomass and a decrease in root fresh weight, with root dry weight remaining relatively stable. Transcriptomic analysis revealed more shared differentially expressed genes and stronger enrichment of N metabolism pathways in shoots, whereas roots showed enrichment of ATP-binding cassette (ABC) transporter and fatty acid elongation pathways. WGCNA identified 500 hub genes in roots and shoots. Five genes in the glutamine synthetase/glutamate synthase (GS-GOGAT) pathway were significantly associated with nitrogen-related traits. SORBI_3001G116400, which encodes glutamate synthase, showed the strongest haplotype effect in 232 sorghum accessions. The A allele (Hap1) was significantly associated with increased plant height, SPAD value, grain number, nitrogen accumulation, and biomass under LN stress, suggesting that SORBI_3001G116400 as a candidate gene requiring functional validation and testing in additional genetic backgrounds.

Agronomy doi: 10.3390/agronomy16151497

Authors: Ruonan Du Qiang Gao Xue Yang Hui Jin Lijun Cai Jumei Zhang Tsvetkov Yordan Dimitrov Haibin Zhao Yu-E Wu Xing Xing Shuang Wang Fei Huang Chunwei Zhou Danna Chang Zhuo Li Ligang Qin Rui Zhang

Although green manure crops are widely recognized for ameliorating alkaline soils, some previous studies have focused mainly on laboratory germination screenings or single yield indicators, and field validation of the synergy between high yield and soil improvement remains comparatively limited. This study evaluated 16 species/accessions with varying salt tolerance in a typical alkaline soil (initial pH 9.01, EC 306 μS·cm−1) in Heilongjiang Province during 2024–2025, based on prior laboratory screening. The experiment was conducted at a single location with three field replicates, and the same plots were monitored across both years. Plant height, fresh/dry grass yield, and soil properties (pH, EC, organic matter, nutrients) were monitored. Glycine max (L.) Merr. and Sesbania Scop. achieved dual synergy, with two-year average fresh yields of 40,733 and 35,750 kg·ha−1, respectively, while reducing soil pH by 0.28–0.29 and electrical conductivity (EC) by 42.2–46.3%. Melilotus officinalis and Vicia villosa Roth exhibited the strongest alkali reduction (pH ↓0.29, EC ↓39.0–39.7%) with moderate yields. Sorghum sudanense showed the highest salt reduction (EC ↓49.0%). Principal component analysis classified the 16 species into four functional types, revealing preliminary ecological patterns for functional differentiation. This study proposes a “laboratory screening–field validation–functional classification” evaluation framework, which requires further validation across different regions and longer time scales for the biological amelioration of alkaline soils.

Agronomy doi: 10.3390/agronomy16151496

Authors: Ziyang Zhu Jing Zhang Fangyuan Chen Wenyan Duan Bohan Wu Di Zhang Patryk Oleszczuk Monika Raczkieiwcz

The impact of biochar on N conversion in drought-affected soil with green manure application has not been systematically investigated. Therefore, this study examined the effects of biochar produced at 350 °C, 550 °C, and 750 °C (BC350, BC550, and BC750) on green manure (Medicago sativa L.) decomposition and N turnover in soil (Hapli-Udic Ferralosol) during a 60-day laboratory incubation experiment under different moisture conditions (45% or 65% soil water-holding capacity (WHC)). Due to low-temperature biochar (BC350) possessing hydrophilicity (thereby enhancing water retention) due to its surface oxygen-containing functional groups, while high-temperature biochar (BC750) relies on the aromatic conjugated π-electron system for electron transfer, both BC350 and BC750 promoted green manure decomposition and mineralization. Compared with green manure alone, co-application of BC350 and BC750 with green manure increased soil NH4+–N content by 5.58% and 38.37%, respectively. However, a significant total N loss (>11%) occurred under drought conditions. Partial least squares path modeling was used to elucidate the key driving pathways related to C and N sequestration in drought-affected soil with green manure and biochar co-application. The results indicate that the enhanced soil N loss could be attributed to both the biochar-induced rise in soil pH (>8%) and the drought-driven suppression of stable organic matter (e.g., >20% reduction in humus acid) and macroaggregate formation. This study demonstrates that although biochar addition can promote the decomposition of green manure to release available N, it may also exacerbate total soil N loss. Only under normal moisture conditions can the N released from green manure be converted into humus-associated N.

Agronomy doi: 10.3390/agronomy16151495

Authors: Yanan Ning Jiaxin Lv Mengwei Dong Yue Wu Yong Liu

Rice is one of the most important food crops in China, and frequent outbreaks of rice pests pose a serious threat to both the yield and quality of rice. Accurate monitoring of rice pests is therefore of great significance for field management and intelligent pest control. In this study, a refined rice pest detector, termed CLM-YOLO, is proposed based on YOLOv11n according to the characteristics of rice pest targets. Specifically, in the backbone network, the original C3k component in the C3k2 block is replaced with an improved RepViT-DBlock to form the C3k2R module, which strengthens early-stage local feature representation and improves the extraction of fine-grained pest-related cues. Additionally, the Multi-Dimensional Grouped Convolutional Block Attention Module (MDGCBAM) is embedded at the transition between the backbone and neck, allowing the network to emphasize pest-related regions while suppressing redundant responses from rice-field backgrounds. Finally, the Local Deformable Attention Adaptive Query Upsampling (LDAAQU) module is adopted in the neck to replace the original upsampling operation. Through deformable attention and query-guided adaptive aggregation, LDAAQU improves the spatial alignment of multi-scale features during feature fusion and enhances the recovery of fine-grained image details. Experimental results show that CLM-YOLO achieves favorable performance on key detection metrics. Specifically, the F1-score, mAP@0.5, and mAP@0.5:0.95 reached 84.37%, 87.8%, and 73.1%, respectively. The proposed method offers a feasible approach for accurate rice pest detection and intelligent pest monitoring in field environments.

Agronomy doi: 10.3390/agronomy16151494

Authors: Masoomeh Shemshad Katarzyna Pużyńska

Agroecological approaches are increasingly recognized as sustainable alternatives to conventional weed management practices. This review examines the role of soybean, potato, and winter wheat as key crops within agroecological systems for effective weed suppression. Four management strategies—crop rotation, post-harvest mulching, optimized planting density (for soybean and potato), and varietal mixtures (for winter wheat)—are evaluated for their influence on weed dynamics and overall system performance. The synthesis of current studies indicates that these practices can significantly reduce weed pressure while enhancing soil health, biodiversity, and the provision of key ecosystem services, including provisioning, regulating, and supporting functions. In addition, these approaches contribute to improved crop productivity and reduced reliance on chemical inputs. Agroecological strategies also support pest regulation, water-use efficiency, and climate resilience, promoting more sustainable and resource-efficient agricultural systems. Despite these benefits, challenges related to farmer adoption, labor requirements, and limited policy support remain. Overall, this review highlights the potential of integrated agroecological practices to achieve sustainable agricultural intensification while balancing ecological sustainability with economic viability. Further research and supportive policy frameworks are needed to facilitate the wider implementation of these approaches across diverse agroecosystems.

Agronomy doi: 10.3390/agronomy16151493

Authors: Qiang Wu Zhu Chen Huihua Ji Wen Sang Zihan Zhang Zhongkai Shen Huacai Chen

Physical control technology as an alternative to chemical pesticides is of great significance for modern sustainable agriculture. However, small pests such as tea green leafhoppers and tea thrips possess sensitive aerodynamic receptors that easily perceive disturbances generated by suction airflow and initiate stress-induced escape behavior. The current bottleneck in the state of the art is that conventional straight tube capture devices generate severe airflow pulsations and turbulence near the intake which act as alarm signals causing pests to escape before entering the effective capture zone. To resolve this trade-off, this study developed and validated a variable cross-section wind-suction channel based on the principle of biological behavioral suppression. This design incorporates a three-stage functional structure consisting of a flow-stabilizing intake section a guided acceleration section and a high negative-pressure throat to achieve a synergistic balance between low disturbance induction and strong aerodynamic confinement. Numerical simulations and prototype experiments show that this design establishes a stable rectified environment at the intake with relative wind speed deviations within 5%. Under controlled laboratory conditions, the average capture rate for target pests exceeded 85% within an effective operating radius of 20 cm. Comparative biological validation further confirms that the capture efficiency of this design is improved by more than 32 percentage points compared with a conventional straight-tube benchmark device. Furthermore, the critical stress-response distance was reduced by approximately 50%, significantly enhancing the concealment of the capture process. These findings elucidate the critical role of channel geometry in resolving the conflict between suction intensity and environmental disturbance providing a theoretical foundation and technical support for the development of high efficiency and precision plant protection equipment.

Agronomy doi: 10.3390/agronomy16151492

Authors: Jessica Erazo Paula Vanella Juan Palazzini Silvana Plem Adriana M. Torres Sofía A. Palacios

Durum wheat is highly susceptible to Fusarium head blight (FHB), a severe fungal disease caused primarily by Fusarium graminearum. FHB affects durum wheat production by causing significant yield losses and grain contamination with mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEA). Given the limitations of chemical fungicides, finding sustainable biological control agents is essential. This study evaluated the antagonistic and biocontrol capabilities of Trichoderma harzianum ITEM 3636 against F. graminearum through in vitro and greenhouse experiments. In vitro dual and sandwich culture assays demonstrated that T. harzianum significantly inhibits pathogen mycelial growth through direct interaction and the emission of volatile compounds. In a competition test on rice kernels, co-inoculation with ITEM 3636 significantly reduced pathogen biomass, leading to maximum reductions of 96.5% for DON and 98% for ZEA. Furthermore, greenhouse trials on a commercial durum wheat cultivar revealed that T. harzianum ITEM 3636 significantly decreased FHB severity by 40% and reduced DON contamination by up to 32% only when a combined seed-coating and spike-spraying application was performed. Additionally, ITEM 3636 exhibited biostimulant-like effects on yield parameters, causing an increase in kernel weight of 33% in the greenhouse assay. These findings highlight T. harzianum ITEM 3636 as a promising and ecological alternative to synthetic fungicides for managing FHB, safeguarding crop production, and ensuring food safety.

Agronomy doi: 10.3390/agronomy16151491

Authors: Nuo-Ya Lou Shyh-Rong Chang Uei-Chern Chen

Driven by global climate change and Taiwan’s Net-Zero initiatives, high-input livestock farming faces urgent pressures to transform. Pennisetum purpureum, a primary forage and bioenergy crop, traditionally relies on heavy chemical nitrogen inputs, thereby exacerbating its carbon footprint. This study evaluated a sustainable cultivation model integrating legume intercropping with reduced fertilization. A field trial in central Taiwan utilizing a Completely Randomized Design (CRD) compared four treatments: conventional full nitrogen (800 kg N/ha), sunn hemp (Crotalaria juncea) intercropping with half nitrogen, sunn hemp intercropping only, and organic compost. We monitored biomass, forage chemistry, and soil organic carbon (SOC) dynamics. The sunn hemp plus half-nitrogen treatment achieved dry matter yields (30–35 Mg/ha) and crude protein levels (7.1–7.4%) statistically equivalent to the full-nitrogen control, significantly surpassing other groups. While short-term SOC stocks (72–81 Mg C/ha) showed no significant differences, trends indicated carbon accumulation in deep soil (30–50 cm). Consequently, substituting 50% of chemical nitrogen through biological fixation proves a viable strategy to maintain yield while reducing inputs. This model sustains productivity and mitigates greenhouse gas emissions, offering an economically feasible, potential carbon-negative solution for tropical forage systems.

Agronomy doi: 10.3390/agronomy16151490

Authors: Shi Cao Xiaoyu Liu Ziwen Zeng

Alfalfa spring black stem and leaf spot (ASBS), caused by Ascochyta medicaginicola, threatens alfalfa yield, forage quality, and stand persistence. Conventional resistance assessments of alfalfa cultivars generally rely on disease incidence, disease severity, or the percentage of healthy plants. Although these measures describe symptom occurrence and development, they do not capture biomass retention or root growth after infection. In this study, 12 alfalfa cultivars were spray-inoculated with A. medicaginicola under greenhouse conditions and evaluated 14 days after inoculation. Disease incidence was positively correlated with the disease severity index and negatively correlated with relative fresh weight, relative dry weight, and relative root length. We integrated these five indicators using a membership-function-based standard-deviation coefficient weighting method to derive a comprehensive response score (D value). D values ranged from 0.0340 to 0.9611. Magnum 2 had the highest D value, followed by Gannong No. 3, Adrenalin, and Dryland, whereas Thunder, Zhongmu No. 1, and Aohan had the lowest values. Compared with the National Alfalfa and Forage Alliance classification based on the percentage of healthy plants, the D-value ranking provided additional discrimination among cultivars within the same resistance class under the present greenhouse conditions. The first two principal components explained 89.24% of the total variation and separated resistant, intermediate, and susceptible response types. Thus, combining disease suppression with growth retention yielded a complementary quantitative description of cultivar performance under the conditions tested.

Agronomy doi: 10.3390/agronomy16151489

Authors: Zhongyi Yu Guangfu Wang Xiongkui He Song Shi Yingbo Gao Kuan Ren Xing Nian Chaogang Li

Professors Gao Wangsheng and Chen Yuanquan confirmed that they only provided general guidance and suggestions in the early stages of the research, and did not participate in substantive work such as experimental implementation, data analysis, and manuscript writing [...]

Agronomy doi: 10.3390/agronomy16151488

Authors: Sandra Cvejić Aleksandra Radanović Dragana Trkulja Svetlana Glogovac Igor Vukelić Mirela Kajkut Zejković Marina Antić Sonja Umićević Jasmin Grahić Mirjana Jankulovska Nadica Sandeva Atanasova Biljana Kuzmanovska Boris Lazarević Eleni Abraham Eleni Tani Efi Sarri Dimitrios N. Vlachostergios Christos Petsoulas Anastasia Kargiotidou Chrysanthi Pankou Rustam Usmanov Bakytzhan Anapiyayev Konirsha Iskakova Nasya Tomlekova Emilia Nacheva Daniela Ganeva Sibel Aziz Ali Şenay Hayrettin Peşkircioğlu Emine Seçer Aslıhan Göktuğ Kadriye Yaprak Kantoğlu Jolanta Kwasniewska Siniša Jocić Ankica Kondić Špika Dragana Miladinović

The review summarizes practical experiences in using mutation breeding for crop improvement in South-Eastern Europe (SEE) and Central Asia (CA), demonstrating that mutation breeding can be a field-validated, effective approach for developing climate-resilient crops. Drawing on coordinated research conducted within national breeding programs and international initiatives supported by FAO/IAEA, applied methodologies, trait-evaluation strategies, and concrete breeding outputs in cereals, legumes, and industrial crops are presented. The use of gamma irradiation, fast neutrons, and chemical mutagens has successfully generated stable mutant lines stable mutant lines with enhanced traits, such as increased thousand-grain weight in wheat, altered oil quality in sunflower, and improved drought tolerance in common bean and sesame. The integration of classical pedigree selection with modern breeding tools such as high-throughput phenotyping, molecular and biochemical markers, and doubled-haploid technology has enabled earlier and more efficient identification of superior genotypes in mutation breeding programs. The review underscores the practical relevance of mutation breeding in contemporary pipelines to maintain yield stability and quality under adverse environmental conditions.

Agronomy doi: 10.3390/agronomy16151487

Authors: Dongliang Qi Wenjun Yue Si Chen

With global warming, both the frequency and intensity of drought–flood abrupt alternation (DFAA) have been increasing, posing a severe threat to the sustainability of crop production. This study involved a two-year rainproof-pond experiment on maize (Zea mays L.) to investigate the effects of varied DFAA combinations on leaf senescence characteristics and grain yield. The treatments consisted of well-watered conditions throughout the maize growing season (CK), maintaining soil moisture at 55–60% of field capacity (D), waterlogging for 6 days (W), and abrupt alternation between drought (D) and slight (3 days), moderate (6 days), and severe (9 days) waterlogging, denoted as D-LW, D-MW, and D-HW, respectively. The water stress was applied at the sixth leaf (V6) stage. Compared to CK, D, W, D-MW, and D-HW significantly decreased the leaf area index, soil and plant analyzer development (SPAD) value, net photosynthetic rate, superoxide dismutase, peroxidase, catalase activities, soluble protein content, shoot biomass, harvest index, ears per hectare, kernels per cob, and 1000-kernel weight, thus significantly lowering grain yield (reduced by 9.4–74.9%). D-LW, however, behaved in the opposite manner and achieved a high grain yield (reduced by 7.0%). Enhanced root growth contributed to the relatively stable grain yield under D-LW. Thus, drought–slight waterlogging abrupt alternation could sustain maize yield by stabilizing leaf size, photosynthesis, antioxidant defense system, shoot biomass, and harvest index.

Agronomy doi: 10.3390/agronomy16151486

Authors: My Abdelmajid Kassem Dounya Knizia Khalid Meksem

Soybean diseases caused by fungal, bacterial, and viral pathogens represent a major constraint to global agricultural productivity. Although molecular phylogenetic analyses have advanced the understanding of pathogen evolution, the extent to which disease phenotypes reflect evolutionary relationships remains poorly understood. In this study, we developed an integrative framework combining deep learning-based phenotypic analysis with phylogenetic inference to investigate the relationship between soybean disease symptoms and pathogen evolution. An EfficientNet-B0 convolutional neural network (CNN) was trained to classify 10 soybean disease classes comprising 703 leaf images and achieved a mean cross-validation accuracy of 98.72 ± 1.17%, a weighted F1-score of 98.74 ± 1.16%, and a macro F1-score of 98.47 ± 1.74%. Evaluation on a held-out test set generated through image-level partitioning yielded an accuracy of 96.19%, a weighted F1-score of 96.28%, and a macro F1-score of 95.86%. Latent feature embeddings revealed a structured phenotypic space with clear separation among most disease classes and enabled quantitative analyses of phenotypic similarity. To provide biological context, taxonomy-derived distance matrices and sequence-based phylogenetic analyses of the fungal subset using 28S rRNA sequences were compared with CNN-derived phenotypic representations. A Mantel test identified a moderate and statistically significant association between phenotypic and phylogenetic distances (Spearman r = 0.3393, p = 0.0050), indicating that pathogen evolutionary history contributes to disease phenotype while explaining only part of the observed phenotypic variation. Overall, the results demonstrate that deep learning effectively captures biologically meaningful phenotypic information while highlighting that disease symptoms arise from the combined influence of pathogen evolution, host responses, and environmental conditions. This study provides an integrative framework for combining image-based phenotyping with phylogenetic analysis to support biologically informed interpretation of plant disease phenotypes.

Agronomy doi: 10.3390/agronomy16151485

Authors: Qing Wang Jingjing Liao Tailin Chen Zhaoming Cai Zhiyi Chen Xueliang Tian Diandong Wang

Clubroot, caused by the obligate biotrophic protist Plasmodiophora brassicae, is a devastating soil-borne disease threatening global cruciferous crop production. To explore non-transgenic control strategies, this study investigated the efficacy of a crude protein extract containing RXLR motif-fused recombinant CRa protein against clubroot in tumorous stem mustard (Brassica juncea var. tumida) and its regulatory mechanisms in the rhizosphere. Mechanistically, fluorescence tracking confirmed that the CRa protein exploits the xylem stream for systemic translocation, colonizing the stele and vascular tissues within 24 h and significantly reducing the disease index. Ecologically, CRa protein reshaped the rhizosphere microbiome by enhancing α-diversity (Shannon and Simpson indices), increasing network complexity, and specifically enriching beneficial genera such as Pseudomonas. Metabolically, CRa protein induced the reprogramming of root exudates, upregulating defensive compounds including jasmonic acid methyl ester, 4-hydroxyglucobrassicin, and (2R)-2-hydroxy-2-phenethylglucosinolate. Overall, exogenous CRa protein activates a coordinated defense response through three key mechanisms: rapid vascular translocation, recruitment of beneficial microbiota, and metabolic reprogramming. This study provides novel insights for developing non-transgenic, microbiome-based green control strategies.

Agronomy doi: 10.3390/agronomy16151484

Authors: Liming Xiao Yanlan Huang Rui Chen Lu Wang Jianfu Wu Zongqiang Wei

Soil C, N, and P, along with their stoichiometric ratios, are important indicators for evaluating soil fertility. However, the dynamics of C:N:P stoichiometry in soils under citrus cultivation of varying durations remain unclear. This study investigated soil C:N:P stoichiometry and extracellular enzyme activities (βG, NAG, and AP) across different soil depths (0–10, 10–20, and 20–40 cm) in navel orange orchards with different ages (3-, 5-, 10-, and 15-year-old). Soils cultivated for 10 years exhibited significantly higher DOC, available N, and P contents compared to other durations. The TC:TN and TC:TP ratios at 0–10 cm were significantly 0.17–4.78 and 3.94–16.1 higher than those at 10–40 cm, respectively (p < 0.05). Notably, the TC:TP and TN:TP ratios observed in the 5-, 10-, and 15-year-old orchards were lower than in the 3-year-old orchard, suggesting an alleviation of P limitation in older orchards. The MBC:MBN ratio remained largely stable with orchard age at 0–20 cm (p > 0.05), whereas younger orchards (3- and 5-year-old) exhibited significantly 18.2–168 and 2.17–17.4 higher MBC:MBP and MBN:MBP ratios than older ones (10- and 15-year-old) at 10–40 cm (p < 0.05). At 0–10 cm, the 15-year-old orchard exhibited higher βG:NAG and βG:AP ratios than the younger orchards. Soil total C:P and microbial C:P ratios explained 29.7% and 20.1% of the variation in enzyme activity composition among abiotic and biotic factors, respectively (p < 0.01). These findings highlight the importance of monitoring P availability in mature orchards to maintain sustainable soil fertility. Future research should focus on long-term field experiments to validate optimal P fertilization thresholds and investigate the specific microbial community shifts driving these stoichiometric changes across different soil depths.

Agronomy doi: 10.3390/agronomy16151483

Authors: Sofiya A. Peshkova Natalya S. Baturina Vladimir V. Molodtsov Kristina V. Popova Sergey Yu. Storozhenko Oxana V. Yefremova Vasily D. Zharkov Michael G. Sergeev

The handsome cross grasshopper Oedaleusdecorus (Germar), which was a minor pest in the 19th and first half of the 20th century, in the late 20th and early 21st centuries, became one of the emerging regional pests in the Asian part of its range, especially across the intermountain basins of the mountains of South Siberia, Mongolia and North and Northeast China. This is why it is necessary to identify the main trends of possible changes in its distribution. Several sets of data on the species distribution (1895–1960, 1961–2023, and all data) are analysed and several various approaches to modelling (graphic, maximum entropy and multidimensional ellipsoid) are utilised. The models produced for modern conditions describe well the known geographical and ecological distributions of the species in the Asian part of its range. Graphic models characterising the species’ distribution within a system of life zones and major ecosystem types show its general preference for dry steppes and semideserts. The models demonstrate apparent opportunities for this species to pierce northwards (at least up to 58° N in West Siberia, 62–63° N in East Siberia) in the future. This means that in the future, there is a certain probability that some individuals will migrate to these more northern regions. In the context of global warming, further northwards and northeastward shifts in the range boundaries of O. decorus can be predicted. In addition, there have been some changes in its population distribution and abundance, especially in the optimal parts of its population system where O. decorus normally colonises all applicable habitats; its average abundance is relatively high and it is common even during depressions. These shifts may be justified by both climatic changes (especially northwards) and some transformations of human activities (mainly for eastwards relocation).

Agronomy doi: 10.3390/agronomy16151482

Authors: Xianyu Cheng Xinyue Zhang Diao Yan Hao Guo Zhigang Yi

Soil acidification severely threatens soil health, tea quality and yield in tea plantations, making it essential to use appropriate soil amendments to address this issue. Biochar can enhance the agricultural soil environment, but its effects on microbial communities, soil fertility, tea quality and yield remain incompletely understood. In this field study, three treatments were applied in a strongly acidic tea plantation: CK (traditional fertilization), BC1 (CK with 4.5 t ha−1 biochar) and BC2 (CK with 9 t ha−1 biochar). Soil chemical properties, microbial communities, tea quality and yield were measured, and their correlations were analyzed. Compared with CK, BC2 significantly increased soil pH from 4.25 to 4.58 and elevated soil total carbon, total nitrogen and ammonium nitrogen by 99.18%, 21.29% and 166.67%, respectively. The BC2 treatment also enhanced soil microbial diversity and increased the relative abundance of potentially beneficial bacterial genera, which were positively correlated with improved tea quality and yield. In particular, BC2 increased free amino acids, water extracts (WE) and tea yield by 10.64%, 13.01% and 13.65%, respectively. Applying biochar at 9 t ha−1 combined with traditional fertilization appears to be a promising management practice under the conditions of this study to improve soil conditions, tea quality and yield in strongly acidic plantations.

Agronomy doi: 10.3390/agronomy16151473

Authors: Đurđica Kovačić Slavko Rupčić Meri Engler Danijela Samac

This study presents a kinetic evaluation of anaerobic co-digestion of pulsed electric field (PEF)-pretreated corn stover using three models: the Modified Gompertz (MG), Logistic, and Reaction Curve (RC). The objective was to assess model performance and improve the interpretation of biogas production dynamics beyond cumulative biogas yield analysis. Experimental data were obtained from batch mesophilic digestion of fine and coarse corn stover fractions subjected to PEF pretreatment with applied voltages of 350 V and 1 kV. All models achieved high coefficients of determination (R2 ≥ 0.97), indicating good agreement between experimental and modeled biogas production curves. However, error metrics and information criteria revealed clear differences in predictive performance. The MG model provided the closest agreement with experimentally determined biogas production potential (Bmax), whereas the Logistic model consistently underestimated both Bmax and the maximum biogas production rate (Rmax). The RC model yielded the lowest prediction errors and favorable information criteria values but showed greater sensitivity to the initial phase of biogas production, occasionally overestimating Bmax and Rmax. Moderate PEF pretreatment increased both Bmax and Rmax, particularly in the fine fractions, without substantially prolonging the lag phase. In contrast, pretreatment at the higher applied voltage resulted in more heterogeneous kinetic responses, including prolonged lag phases and increased variability of kinetic parameters.

Agronomy doi: 10.3390/agronomy16151481

Authors: Anna Westerbergh Mohammad Sameri Estelle Lerceteau Köhler Per-Olof Lundquist

Perennial wild relatives of annual crops possess traits associated with stress tolerance, efficient nutrient uptake, and increased soil carbon sequestration. They therefore represent valuable genetic resources for developing perennial crops that may reduce environmental and climate impacts and enhance food security. We evaluated 151 introgression lines (ILs) derived from crosses between barley and the perennial relative Hordeum bulbosum, each carrying unique H. bulbosum chromosome segments in a barley genetic background. Growth and regrowth after harvest were evaluated in two field trials, established by spring and fall planting in separate years in central Sweden, and under simulated two-year seasonal cycles in a climate chamber. In the climate chamber, 54% of the ILs exhibited strong regrowth, and two-thirds of these ILs showed reproductive growth across two seasonal cycles. In the field, most ILs showed regrowth after harvest but did not survive the cold winter. The parental genetic background had a strong effect from the barley parent on several growth and reproductive traits, but some ILs exhibited phenotypes not expected based on the barley parent. Of the divergent ILs with high regrowth, identified by PCA combining all studied traits, H. bulbosum introgressions at chromosome arms 2HL and 4HL were highly represented among ILs with cultivar Emir as a barley parent, and introgressions at 1HL among ILs with cultivar Morex as a parent. Perennial growth was observed only under mild conditions, indicating that perenniality of these ILs in a cold-temperate climate requires not only regrowth capacity but also adaptation to photoperiod, vernalization, and frost. ILs with high regrowth and reproductive growth may be used in crossing efforts with cold-tolerant germplasm to support the development of perennial barley.

Agronomy doi: 10.3390/agronomy16151480

Authors: Chunxu Zhao Guodong Nai Yujuan Zhang Wenke Dong

Poa pratensis var. anceps cv. Qinghai is a high-quality forage grass widely distributed across the Qinghai–Tibetan Plateau, exhibiting exceptional cold tolerance, a well-developed root system, and outstanding soil consolidation capacity, rendering it of great significance for ecological management in alpine regions. Jasmonic acid (JA), as an endogenous phytohormone, plays a pivotal role in regulating low-temperature adaptation and is hypothesized to be a core regulatory hormone underlying the cold tolerance of this cultivar. In this study, using seedlings of P. pratensis var. anceps cv. Qinghai (PQ) and the cold-sensitive cultivar P. pratensis “Barun” (PB) as a control, exogenous methyl jasmonate (MeJA, a JA analog) and the JA biosynthesis inhibitor DIECA were applied, and physiological and transcriptomic analyses were conducted to elucidate the mechanism by which JA regulates low-temperature adaptation. The results showed that MeJA significantly alleviated the growth inhibition induced by low temperature (4 °C) in both materials, with a more pronounced effect in PQ. Specifically, compared with the corresponding cold-only controls, MeJA treatment increased chlorophyll content by 5.55% in PQ and 22.40% in PB after 72 h of cold stress; soluble sugar content by 61.40% and 33.40%; soluble protein content by 47.16% and 36.50%; and proline content by 80.82% and 59.17%, respectively. MeJA also enhanced antioxidant enzyme activities, with SOD increasing by 49.28% and 15.61%, POD by 73.93% and 43.10%, CAT by 36.68% and 12.95%, and APX by 53.05% and 21.10% in PQ and PB, respectively. Additionally, non-enzymatic antioxidant contents (GSH and AsA) increased by 15.55% and 48.31% in PQ, versus 3.37% and 19.54% in PB. In contrast, DIECA suppressed these enhancements, with a more distinct inhibitory effect on PB, confirming that the JA pathway is a critical mechanism mediating low-temperature response in PQ, with significantly higher regulatory efficiency than that in the control. Transcriptome sequencing generated 1.787 million transcripts and identified 16,267 differentially expressed genes (10,054 up-regulated, 6213 down-regulated) in the MeJA-treated PQ group. GO and KEGG enrichment analyses revealed pathways associated with photomorphogenesis and carotenoid biosynthesis. Weighted gene co-expression network analysis (WGCNA) identified two core modules, and eight key genes including PpHY5 and PpCOR410 were screened, suggesting their coordinated roles in JA-mediated cold tolerance. These findings provide a comprehensive physiological and transcriptomic basis for understanding JA-enhanced cold tolerance in PQ seedlings.

Agronomy doi: 10.3390/agronomy16151479

Authors: Bingqian Su Yanyan Zi Wenlong Xu Yaobin Wang Zhuoxia Su

Water availability strongly influences nutrient utilization and plant adaptive strategies, yet how nitrogen (N) and phosphorus (P) supply interact with water conditions to regulate leaf functional traits remains insufficiently understood. In this study, Robinia pseudoacacia L. seedlings were subjected to contrasting water regimes combined with N and P additions to examine leaf morphological, structural, physiological, and stoichiometric traits. The results showed that water availability significantly modulated seedling responses to N and P supply. Under well-watered conditions, nutrient addition promoted leaf growth and biomass accumulation, whereas under water deficit, seedlings enhanced osmotic adjustment and altered resource allocation. Significant interactions among water, N, and P were observed for leaf morphological, physiological, and stoichiometric traits. Soil organic carbon (SOC), total nitrogen (TN), and available phosphorus (AP) in rhizosphere soil were the soil factors most strongly associated with the variation in leaf functional traits, among which SOC exhibited the highest explanatory power. Functional trait network analysis revealed that specific leaf area (SLA) and leaf nitrogen-to-phosphorus ratio (N:P) were identified as central hubs of the leaf trait network. Overall, drought shifted R. pseudoacacia seedlings from a resource-acquisitive strategy toward a resource-conservative and stress-tolerant strategy. This study elucidates the short-term response patterns of R. pseudoacacia seedlings to combined water and nutrient stress, providing preliminary insights for water and fertilizer management during seedling establishment in arid regions.

Agronomy doi: 10.3390/agronomy16151477

Authors: Annamaria Di Serio Alfredo Lorenzo Lisa Antonucci Nausicaa Occhipinti Enrica De Falco Domenico Ronga Giancarlo Pagnani Michele Pisante

Wheat is a major staple crop, and improving its productivity and grain quality is essential to meet rising global food demand. Biostimulants have attracted growing interest because they can enhance nutrient use efficiency, improve tolerance to environmental stresses, and support crop performance without acting as conventional fertilizers, yet a focused synthesis of their effects on wheat remains limited. Following a systematic search of Scopus and Web of Science (2000–2026), this review synthesizes 52 primary studies on microbial and non-microbial biostimulants in common and durum wheat, addressing grain yield, nutritional quality, and resilience to drought, salinity, heavy metals, and temperature extremes. Across studies, 88% reported significant positive effects and none reported a consistent negative effect; grain yield increases ranged from +6% to +123%, with parallel improvements in grain protein and micronutrient biofortification, notably zinc and iron. Microbial biostimulants, especially bacteria and microbial consortia, produced the largest but most variable gains, whereas non-microbial products gave more moderate and consistent responses. Benefits were greatest under low nitrogen, drought, and saline conditions and in nutrient-poor soils, and were modulated by wheat genotype and product dose. Biostimulants are promising tools for sustainable wheat production, though standardized field trials and reporting are still needed.

Agronomy doi: 10.3390/agronomy16151478

Authors: Chuhuang Zhou Tanghua Wang Xin Zeng Fei Wang Fanfei Meng Zheng Yang Min Dong

Fruit preharvest–postharvest quality assessment is essential for precision harvesting, intelligent grading, storage management, and supply-chain loss reduction. However, conventional approaches mainly rely on single-point postharvest inspection and cannot adequately capture the long-term effects of preharvest fruit phenotypes and environmental dynamics on quality formation. To address limited prediction accuracy under few-label conditions, insufficient multimodal fusion, and weak cross-orchard generalization, this study proposes FruitSSL-QNet, a self-supervised multimodal learning framework for jointly modeling preharvest fruit images, environmental sensor time series, and postharvest quality indicators. The framework employs visual masked reconstruction to learn fine-grained phenotype features, including color, texture, lenticel distribution, disease spots, and maturity patterns. Environmental temporal masked modeling is used to capture the cumulative effects of temperature, humidity, light intensity, soil moisture, and rainfall. Bidirectional cross-attention, gated fusion, and contrastive alignment are further integrated to learn complementary and semantically consistent image–environment representations. Experimental results demonstrate that FruitSSL-QNet outperforms SVM, Random Forest, XGBoost, LSTM, GRU, TCN, Transformer, and MM-Transformer across multiple quality assessment tasks. The proposed model achieves a maturity recognition accuracy of 89.6%, exceeding MM-Transformer by 4.4 percentage points. Compared with the corresponding baseline results, the prediction errors for sugar content, firmness, and shelf life are reduced by 21.1%, 22.2%, and 22.5%, respectively. The decay-risk AUC reaches 0.921, and the cross-site F1-score reaches 0.867, indicating strong risk discrimination and stable generalization across orchard environments. Ablation experiments further confirm the contributions of visual self-supervision, environmental temporal self-supervision, and cross-modal alignment.

Agronomy doi: 10.3390/agronomy16151476

Authors: Dianyong Jia Yuli Xie Qiankun Li Ting Lei Pengfei Duan Wei Chang Xilei Song Yaoyao Zhang Ying Liu

Closing yield gaps in wheat production requires optimized cultivar selection and nitrogen (N) management; however, the cultivar-specific responses to N fertilizer and soil fertility remain largely unquantified. Twenty-eight wheat cultivars were evaluated under three fertilization treatments (T) (CK, no-fertilizer; N1, 210 kg N ha−1 as single basal application; and N2, split-N at 105 + 105 kg N ha−1, applied only in 2022–2023 and 2023–2024) over three growing seasons in the Huang-Huai region. Two-way interactions (cultivar × T, cultivar × year, and T × year) and the three-way cultivar × T × year interaction were significant (p < 0.001), whereas the year main effect was not significant (p = 0.329). Fertilization accounted for the largest proportion of yield variance (η2 = 0.589), followed by cultivar × year (η2 = 0.244) and cultivar (η2 = 0.141). Yield ranged from 3435 to 5231 kg ha−1 (a 1.52-fold difference). Hierarchical clustering of basic soil productivity contribution rate (BSPCR) classified cultivars into high, moderate, and low soil fertility dependence classes, enabling fertility-based cultivar matching. Within-cultivar correlation analysis identified spike number as the predominant yield-limiting factor (71.4%). Based on composite scores integrating yield, stability, split-N response index (SNRI), and BSPCR, Tier I cultivars (C20, C1, C21, C14) are recommended for high-fertility fields with split-N application, combining high yield (5004–5231 kg ha−1), strong N responsiveness (SNRI ≥ 1.10), and high BSPCR; Tier II cultivars (C7, C3, C18, C12, C22) offer a balanced performance in yield and stability. The proposed tiered system—prioritizing Tier I and Tier II cultivars according to field fertility and production goals—provides an exploratory, site-specific framework for closing wheat yield gaps in the Huang-Huai region.

Agronomy doi: 10.3390/agronomy16151471

Authors: Zdenko Lončarić Ivana Varga Aleksandra Sudarić Vladimir Zebec Jurica Jović Katarina Perić Franjo Nemet

Zinc (Zn) biofortification is a promising agronomic approach for improving crop nutritional quality and reducing the accumulation of toxic elements in edible plant parts. The aim of the present study was to evaluate differences in Zn and Cd status and accumulation among Zn-biofortified soybean genotypes grown under alkaline soil conditions. This study was conducted in Eastern Croatia with six soybean genotypes (0–1 maturity group): Ika, Korana, Lucija, Sonja, Sunce, and Toma (Agricultural Institute Osijek, Osijek, Croatia). Foliar biofortification treatments were applied at the beginning of flowering at 0 (control), 3 kg/ha (Zn_1), and 6 kg/ha (Zn_2). Even though the genotype Ika had the highest Zn-bioconcentration value across all treatments and both years, the Toma genotype had the highest seed Zn concentration (64.87 mg/kg), whereas the Sonja genotype had the highest leaf Zn concentration (405 mg/kg). Biofortification treatments significantly (p < 0.001) increased soybean seed Zn content, with the highest increment under Zn_2. Averaged across both Zn biofortification treatments, Cd concentration in the soybean seed decreased by 33.4% in 2020 and by 45.8% in 2021 as compared to the control (31.53 and 51.47 µg/kg, respectively). Regarding the genotypes, under Zn treatment, Ika, Korana, Lucija, and Toma showed increased Zn concentrations but decreased Cd concentrations compared with the control, whereas the Sonja and Sunce genotypes showed a distinct response, with both Zn and Cd increasing under Zn treatments, indicating a possible synergistic interaction between Zn and Cd uptake. Generally, the findings indicate that foliar Zn biofortification on alkaline soil can improve soybean seed nutritional quality by increasing Zn concentration and further reduce the already low seed content of Cd.

Agronomy doi: 10.3390/agronomy16151475

Authors: Zhihao Xu Zheren Tong Hanxiang Huang Hongyu Xu Shaoxian Wang Zhiwen Zhang Tao Lv Fujia Luan Peishi Feng Jianhong Zhang Zijin Xu Ping Wang

Background: Saffron corm rot causes significant yield losses worldwide. Although synthetic pesticides are commonly used for management, their overuse can lead to increased fungal resistance and pose a risk to public health. Numerous plants possessing antifungal properties hold significant potential for development as biocontrol agents against saffron corm rot. Result: In this study, the efficacy of biocontrol agents derived from natural plants was evaluated for managing saffron corm rot. Aqueous and 70% ethanol extracts from 15 plants were investigated for antifungal activity and virulence suppression against three saffron pathogens: Fusarium oxysporum, Penicillium citrinum, and Aspergillus brasiliensis. Antifungal activity experiments indicated that clove ethanol extract at a concentration of 20 mg/mL exhibited the highest inhibition rate, with values of 93.27 ± 0.0% for Fusarium oxysporum, 86.47 ± 5.55% for Penicillium citrinum, and 68.65 ± 2.40% for Aspergillus brasiliensis. Compared with the model group, clove ethanol extract significantly reduced corm rot and normalized the metabolism of infected corms. On day 30, compared with the model group (34.3 ± 3.7%), the rot rate of clove-treated corms was reduced to 17.2 ± 1.4%, and on day 60, it was reduced to 27.5 ± 1.5% (versus 52.9 ± 3.3% in the model group). Compared with the model group, the levels of soluble sugar, starch, α-amylase, soluble protein, and superoxide dismutase in clove-treated infected corms approached those observed in the control group. Field trials confirmed that clove ethanol extract effectively improved plant growth and reduced the disease severity index (37.00 ± 3.51) in infected corms. Conclusion: Clove ethanol extract is a promising candidate to replace or reduce the use of synthetic pesticides. It provides a theoretical and practical basis for the biocontrol of saffron corm rot.

Agronomy doi: 10.3390/agronomy16151474

Authors: Mauricio Salas-Salinas Joao Renzo Enrique Santos-Juanillo Anacelly Valera López Alonso Roberto Poma Ticona

Salinity and drought are major abiotic stresses responsible for substantial losses in global agricultural productivity, particularly in arid and semi-arid regions. Although Bacillus spp. are widely studied as plant growth-promoting rhizobacteria (PGPR) capable of enhancing plant tolerance to abiotic stress, the extent to which this research has addressed combined salinity and drought stress remains underexplored. This study conducted a bibliometric analysis of scientific output and experimental evidence available in the Scopus-indexed literature published between 2016 and 2024 on Bacillus spp. as PGPR under combined salinity and drought stress conditions. A total of 479 documents were analyzed using the Bibliometrix R package v. 5.4.1 in R v. 4.5.3 and VOSviewer v. 1.6.20, applying Bradford’s and Lotka’s laws, keyword co-occurrence analysis, and citation analysis. Scientific output exhibited a compound annual growth rate of 24.5%, reaching 103 publications in 2024. China, India, and Pakistan were the leading contributors. Among the 495 eligible studies, only 2 studies identified through the primary Scopus search experimentally evaluated Bacillus spp. as PGPR under combined salinity and drought stress conditions. A third study was identified through a complementary external search, revealing a critical gap in experimental in vivo evidence under combined stress conditions. Addressing this gap is essential for advancing effective bioinoculant development for sustainable agriculture under combined abiotic stresses.

Agronomy doi: 10.3390/agronomy16151472

Authors: Zhiqi Wang Yunna Ao Ganghua Zhou Xinran Yang Dong Yin Xinyue Zhang Yujie Shi Junfeng Wang

The tiller number of perennial grasses responds strongly to soil nitrogen availability, and critically governs aboveground biomass production. Plant NRT2 proteins are major components of the high-affinity nitrate transport system, and contribute to nitrate uptake and distribution, with gene-specific functions depending on tissue context, interacting partners, and nitrogen availability. However, few studies have explored the function of the NRT2 proteins in Leymus chinensis. In this study, 28 LcNRT2 genes were first identified in the L. chinensis genome. Phylogenetic analysis indicated that the 28 LcNRT2 genes were classified into four distinct clades. Gene structure analysis demonstrated that 82.1% of LcNRT2 genes were characterized by a lack of introns. While, 17.9% possessed only a single intron. Chromosomal localization indicated that 28 LcNRT2 genes were distributed on 8 of 14 chromosomes of L. chinensis. No LcNRT2 genes were identified on chromosomes 1Ns, 2Ns, 2Xm, 4Ns, 5Ns, and 5Xm. Six LcNRT2 genes were isolated from the nitrogen-induced transcriptome dataset of L. chinensis and exhibited significantly upregulated expression. LcNRT2.21 was significantly upregulated under nitrogen treatment, and was, therefore, studied in more detail. The heterologous overexpression of LcNRT2.21 in rice increased tiller number, decreased plant height, and altered the expression of tillering-related genes OsTB1, OsMOC1, OsYUCCA4 and OsAUX1. These results demonstrated that LcNRT2.21 may play a vital role in improving tiller numbers in plants.

Agronomy doi: 10.3390/agronomy16151470

Authors: Lin Gou Shang Shi Xi Li Hongyi Wang Ling Liu Xiao Wei Rong Zou Chenghao Zhu Jianmin Tang

In this study, three-year-old seed-derived seedlings of Horsfieldia hainanensis Merr. were subjected to 0%, 25%, 50%, and 75% shade treatments in a nursery shade-net experiment from October 2025 to June 2026. Each treatment included three replicates, with three seedlings per replicate. The results showed that the light environment significantly affected growth. Seedlings under 0% shade showed severe wilting and mortality; therefore, this treatment was treated as a mortality outcome and excluded from subsequent statistical comparisons, which were conducted among the 25%, 50%, and 75% shade treatments. Within this range, plant height, ground diameter, crown width, leaf traits, and above- and belowground biomass increased with shade level, with the highest values observed under 75% shade. The 75% shade treatment was associated with higher maximum net photosynthetic rate (Pmax), apparent quantum yield (AQY), initial carboxylation efficiency (α), and CO2-saturated net photosynthetic rate (Amax), together with lower light compensation point (LCP) and carbon dioxide compensation point (CDCP), indicating improved light- and CO2-response performance within the tested shade range. Leaf thickness, epidermal thickness, and palisade and spongy parenchyma thicknesses increased with shade level, whereas variation in stomatal traits was mainly reflected in stomatal density. Chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids increased under stronger shading, showing clear variation in pigment accumulation along the shade gradient. Growth, biomass, photosynthetic capacity, leaf anatomical traits, and pigment contents were positively correlated, whereas the light saturation point (LSP), LCP, carbon dioxide saturation point (CDSP), and CDCP were generally negatively associated with these traits. Among the surviving treatments tested, the 75% shade treatment produced the best seedling performance and may be suitable for nursery cultivation, although further validation at different sites and in different seasons is needed. These findings provide practical guidance for artificial propagation, seedling production, plantation establishment, and light-environment management of this species.

Agronomy doi: 10.3390/agronomy16151469

Authors: Qiqi He Ting Ma Yongjie Li Tao Wu Boxiao Wu Xiye Ma Yubo Liu Lianchun Wang Delu Ning

A reasonable branch bending angle is essential for optimizing canopy structure and regulating metabolic distribution in fruit trees. ‘Jinyefoxilan’ is a new olive variety bred by crossing ‘Frantoio’ and Olea cuspidata Wall., characterized by rapid growth and high oil concentration. This study evaluated the physiological and metabolic responses of ‘Jinyefoxilan’ to natural growth (CK), 60°, 90°, and 110° bending. Parameters including leaf morphology, photosynthetic pigments, endogenous hormones, mineral distribution, and fruit quality were analyzed. The results demonstrated that the 60° treatment stimulated leaf gibberellin synthesis. The 90° treatment facilitated the synergistic enrichment of nitrogen and potassium in leaves, resulting in the highest fruit oil concentration, although the yield per plant was the lowest among all treatments. Conversely, 110° bending significantly altered the endogenous hormonal balance, with indole-3-acetic acid concentration reaching 13.3 times that of the CK. This treatment achieved the numerically highest fruit set rate and yield per plant, accompanied by significant accumulations of calcium, magnesium, and phosphorus. However, the 110° angle also induced severe N and K deficits, resulting in the lowest fruit moisture and oil concentration. In conclusion, 90° branch bending represents the optimal strategy for enhancing intrinsic fruit quality and oil accumulation. Although 110° bending maximizes yield, it necessitates supplemental potassium fertilization during fruit development to mitigate metabolic limitations. These findings provide a theoretical and practical basis for canopy management and cultivation of ‘Jinyefoxilan’ olives.

Agronomy doi: 10.3390/agronomy16151468

Authors: Yixun Qin Yuanzhe Ma Shangyan Hao Yunmei Wu Fuyong Wu

This study investigated the efficacy and mechanisms of foliar-applied selenium nanoparticles (SeNPs) in reducing cadmium (Cd) concentrations and alleviating Cd toxicity in winter wheat grown in Cd-contaminated soil. Pot experiments were conducted to evaluate SeNPs of different particle sizes (50, 100, 200 nm) and concentrations (0.125, 0.25 mmol/L). Foliar SeNPs application achieved the dual objectives of significantly decreasing Cd while increasing selenium (Se) concentrations in wheat grain. High-concentration (0.25 mmol/L) SeNPs treatments were most effective, particularly with a particle size of 100 nm size. Compared with the control, SeNPs significantly reduced grain Cd concentrations by 18.9–70.5% and increased grain Se concentrations by 1.2–27.2 times. Durum wheat exhibited a stronger response than soft wheat. The primary mechanisms included: (1) enhancing antioxidant defense: SeNPs significantly boosted superoxide dismutase (55.2–165.2%) and peroxidase (36.5–182.6%) activities, effectively scavenging reactive oxygen species, reducing oxidative stress markers malondialdehyde (12.0–35.1%) and regulating hydrogen peroxide (7.9–64.1%), which mitigated membrane lipid peroxidation. (2) Regulating subcellular Cd distribution: SeNPs increased the proportion of Cd immobilized in the cell wall by 2.9–39.6% and decreased Cd in organelles by 9.1–38.4%, thereby reducing its bioavailability and toxicity. This study provides a theoretical basis for using foliar SeNPs to remediate Cd pollution and simultaneously produce Se-enriched functional wheat.

Agronomy doi: 10.3390/agronomy16151465

Authors: Ziyi Dou Kesi Liu Yinke Du Guizhen Li Lingling Wang Jumei Fang Yujie Wang Likai He Wei Zheng

Root foraging efficiency under low-phosphorus (P) conditions is a critical constraint for the sustainable development of artificial grasslands. However, the mechanisms by which legume–grass mixtures with complementary deep and shallow root systems regulate soil P availability remain unclear. Based on the hypothesis that root niche differentiation drives stratified soil P utilization, a two-year pot experiment was conducted on these intercropped forages with chernozem soil from 77th Regiment, Zhaosu, Yili, Xinjiang, China. The experiment included monocultures and two mixed-sowing combinations (Medicago sativa/Bromus inermis (AB) and Trifolium pratense/Bromus inermis (CB)) with two sowing patterns (intra-row and inter-row mixed sowing). The results indicated the following: (1) Relative to the CB–intra-treatment, the AB combination increased aboveground and belowground biomass by 39.2% and 138.5%, respectively, and enhanced phosphorus accumulation by 42.2% (inter-row) and 46.7% (intra-row). The land equivalent ratio (LER) of all mixed-sowing treatments was greater than 1, exhibiting stable overyielding performance. (2) Mixed-sowing significantly regulated vertical soil P distribution and rhizosphere P enrichment. The AB combination exhibited significantly superior root phenotypes, associated with deep rhizosphere P content, suggesting a differentiated soil-layer P capture pattern relative to the CB combination. (3) Root volume was the primary factor influencing P use efficiency (PUE), and the mixed-sowing system exhibited a pronounced stratified regulation characteristic: in topsoil, PUE appeared to be synergistically regulated by roots and rhizosphere P; in subsoil, PUE relied primarily on root volume to alleviate low-P stress, achieving efficient deep P utilization. (4) This study proposed a potential topsoil rhizosphere P supplementation threshold range of 4.47–4.899 mg·kg−1. Mixed-sowing forage grasses achieved stratified P utilization in deep and shallow soil layers through root niche differentiation, offering potential quantitative references and practical guidance for efficient establishment and sustainable P management of artificial grasslands in low-P habitats.

Agronomy doi: 10.3390/agronomy16151467

Authors: Valentina Formica Natalia Torres-Pagán Daniela Rodríguez Blessing Ogangwu Massimo Onor Celia Duce Paolo Guarnaccia Daniela Romano Mercedes Verdeguer

Mediterranean aromatic plants are valuable sources of essential oils (EOs) with biological properties that hold promise for sustainable weed management. This study evaluated the phytotoxic activity of EOs from Thymus vulgaris L., Lavandula angustifolia Mill., and Salvia officinalis L. in vitro against key weed species common to Mediterranean agroecosystems. The EOs were tested at concentrations ranging from 0.125 to 1.50 µL mL−1, assessing their impact on seed germination and early seedling growth of Avena fatua L., Lolium rigidum Gaudin, Sonchus oleraceus L., and Amaranthus retroflexus L. Thyme EO, primarily composed of thymol and γ-terpinene, exhibited the strongest phytotoxic activity, completely inhibiting the germination of A. fatua, L. rigidum, and S. oleraceus at all concentrations tested. In contrast, A. retroflexus was the most resistant weed species, with germination fully inhibited only at concentrations ≥ 0.50 µL mL−1. Lavender EO, rich in linalool and linalyl anthranilate, demonstrated a more species-specific effect. It almost entirely suppressed the germination of S. oleraceus at all doses and inhibited germination of A. fatua and L. rigidum at concentrations ≥ 0.50 µL mL−1. Again, A. retroflexus was the most tolerant species, with complete inhibition occurring only at the highest concentrations applied. Sage EO, containing eucalyptol and thujone as its main constituents, was the least effective, fully inhibiting S. oleraceus germination at concentrations ≥ 1.00 µL mL−1, and L. rigidum at 1.50 µL mL−1. Seedling growth was highly sensitive to EO treatments, even when germination was not entirely suppressed. These results highlight the potential of Mediterranean Lamiaceae EOs as plant-derived bioherbicides for integrated weed management.

Agronomy doi: 10.3390/agronomy16151464

Authors: Ruixin Yan Haoran Yue Haopeng Zhou Ruoning Zhu Tao Liu Jia Gu Bangyuan Feng Ye Tian

Continuous monoculture in poplar plantations often leads to declining soil nutrient availability and productivity. Phosphorus (P), in particular, frequently becomes a key limiting factor due to its high fixability and low chemical availability in the soil. Understory vegetation, however, may promote soil P cycling and enhance P availability by regulating the community structure and decomposition activity of soil microorganisms. In this study, a seven-year field experiment was conducted in degraded poplar plantations using a randomized complete block design to investigate the effects of four understory vegetation treatments—understory removal (UR), planting of a nitrogen-fixing species Sesbania cannabina in understory (PN), retention of a single dominant understory species Echinochloa crus-galli (RS), and retention of diverse understory vegetation (RD)—on soil P fractions and availability, and to elucidate the microbial mechanisms driving P cycling using a metagenomic approach. The results showed that, compared with UR, all understory retention treatments significantly increased soil labile P fractions, improved microbial community structure, and enhanced the abundance of P cycling-related functional genes and associated enzyme activities. Specifically, PN enriched the bacterial phylum Chloroflexi, thereby strengthening its role in P cycling, and increased the abundance of key functional genes such as ppa and phnH. These changes led to higher activities of acid phosphatase, phosphodiesterase, and phytase, ultimately improving soil P availability. In contrast, through the input of litter with greater diversity and higher biomass, RD enriched microbial communities dominated by Proteobacteria. This treatment increased the abundance of P cycling-related genes (e.g., phnW, purK, phnP, ugpQ) and associated enzyme activities, thereby enhancing soil P mobilization. Both the introduction of nitrogen-fixing species and the increase in understory species richness promoted soil P cycling and enhanced P availability, albeit through distinct mechanisms. Planting of nitrogen-fixing species enriched specific microbial taxa and functional genes, whereas increasing understory species richness boosts P cycling by increasing bacterial species richness and functional gene abundance. Both enhancing species richness and planting nitrogen-fixing species in the understory effectively improved soil P availability and supported the sustainable management of degraded poplar plantations. Among these approaches, retaining diverse understory vegetation is more cost-effective and contributes to biodiversity conservation, making it a recommended management strategy.

Agronomy doi: 10.3390/agronomy16151466

Authors: Tingting Huo Songrui Ning Deyi Geng Yang Wu An Yan Ning Li Jiashuo Gao Yusen Wang

Silage maize is an important forage crop in China and globally. Applied nitrogen (N) is crucial for increasing the harvest yield (aboveground dry matter) of silage maize. However, there is a lack of information on how nitrogen rate affects the harvest yield of silage maize in different planting regions and under different climatic and soil conditions in China. A meta-analysis was conducted to quantify and evaluate the effects of N rate on the harvest yield and N fertilizer contribution rate of silage maize in China and different planting regions in the country based on research published from 2000 to 2025. The effects of mean annual temperature, annual precipitation, soil properties, planting density, and cultivar used on the maize yield response were also investigated via subgroup analysis. The means of the N rate, harvest yield, and N contribution rate for silage maize in China were 211 kg ha−1, 20,117 kg ha−1, and 27%, respectively. In the southwest hilly and mountainous region, silage maize exhibited the highest harvest yield-change rate (55.41%) under a N rate of >0–100 kg ha−1. In Northern China, the Huang-Huai Plain region, and the southern hilly region, the maximum harvest-yield-change rates for silage maize (31.42%, 54.11%, and 42.66%) were observed at a N rate of >200–300 kg ha−1. In northwest inland China, the maximum harvest-yield-change rate (50.76%) of silage maize occurred at a N rate of >300 kg ha−1. Furthermore, the aggregated boosted tree algorithm was adopted to quantify the relative contribution of N rate, annual mean temperature, annual precipitation, soil pH, soil organic matter, soil type and texture, cultivar selected, and planting density to the harvest yield and N contribution rate of silage maize. Soil type made the greatest contribution to the yield of silage maize in China, accounting for 41.36%, followed by cultivar (40.28%) and planting density (5.97%), and the total contribution of the three factors reached 87.61%. Soil type exhibited the highest contribution (26.35%) to the N contribution rate of silage maize in China, followed by cultivar (22.36%) and planting density (15.11%). The combined contribution of the three factors was 63.82%. Based on the dual criteria of maximizing harvest yield and the N contribution rate, the optimal N rates found for silage maize were 173–300, 110–200, 311–395, 168–270, and 92–270 kg ha−1 for Northern China, the Huang-Huai Plain region, northwest inland China, the southern hilly region, and the southwest hilly and mountainous region, respectively. Meanwhile, in Northern China, the Huang-Huai Plain region, northwest inland China, the southern hilly region, and the southwest hilly and mountainous region, the increase in the yield of silage maize at harvest reached its maximum, and the corresponding silage maize cultivars were Yayu 8, Baimaya, Xinyu 9, Aoyu 5102, and Yuqingyu 3, respectively. This study provides reasonable guidance on suitable N rates for improving the yield and N contribution rate of silage maize in China and various other planting regions.

Agronomy doi: 10.3390/agronomy16151463

Authors: Caterina Capri Camilla Farolfi Claudio Zaccone Ettore Capri Lucrezia Lamastra

The increasing environmental impacts of conventional agriculture have intensified the search for farming approaches capable of balancing food production, resource efficiency, and ecosystem protection. In this context, multiple sustainability-oriented approaches have emerged, including organic agriculture, integrated production, sustainable agriculture, and regenerative agriculture. This study develops a comparative framework based on a structured literature review covering the period January 2000–March 2026 to assess these approaches from both practice-based and governance perspectives. The analysis examines key environmental management dimensions, alongside governance-related aspects. The results reveal substantial convergence across approaches regarding core environmental practices, including cover cropping, crop diversification, reduced tillage, and input optimisation. However, important differences emerge in system integration, governance structures, and sustainability objectives. Efficiency-oriented approaches mainly prioritise productivity and resource optimisation, whereas regenerative and organic approaches place stronger emphasis on ecosystem restoration and soil health. The study highlights the limitations of current sustainability assessment frameworks and emphasises the need for integrated, outcome-based approaches capable of capturing both environmental impacts and regenerative benefits across agricultural systems.

Agronomy doi: 10.3390/agronomy16151462

Authors: Baohua Li Qi Jia Mujun Han Xinxin Liu Weidong Qu Yan Fang Fude Liu Hailong Wu

Coastal riparian zones are important transitional areas for carbon cycling between terrestrial and aquatic ecosystems. However, the associations among litter-derived dissolved organic matter (DOM), soil DOM composition, and soil organic carbon (SOC) fractions across habitats remain insufficiently understood. This study aimed to clarify SOC fraction distribution in woody and herbaceous habitats and evaluate its associations with litter-derived DOM, soil DOM composition, and soil environmental factors in different seasons from a coastal riparian zone. In this study, woody habitats had higher SOC content in March, whereas herbaceous habitats showed greater SOC content in November. Particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) were generally higher in different habitats. MAOC accounted for a large proportion of the measured SOC-related pools and showed a consistent positive association with SOC content. Soil DOM consisted of protein-like and humic-like components, with herbaceous habitats showing a stronger protein-like component and woody habitats showing a stronger humic-like component in March. Woody litter showed greater DOC and DON release potential than herbaceous litter leachates, while litter-derived humic-like DOM was closely associated with a soil humic-like component. The labile SOC pool was mainly associated with vegetation type and electrical conductivity, whereas MAOC was positively associated with soil moisture content and total phosphorus. Overall, the distribution of SOC fractions in coastal riparian habitats is shaped by habitat-specific environmental factors, including vegetative carbon inputs, litter leaching and soil physicochemical properties. This finding is critical for developing targeted management strategies to facilitate SOC accumulation in coastal zones.

Agronomy doi: 10.3390/agronomy16151460

Authors: Nurbolat Mukhanov Nurlan Serekpayev Adilbek Nogayev Balzhan Akhylbekova Nazken Zhetibaikyzy Assel Tumenbayeva Nurgeldy Jakupov Almas Kurbanbayev Aruzhan Oralbay Fujiang Hou

Soil moisture conservation is critical in arid and semi-arid agroecosystems, but open-top laboratory mass-loss tests quantify evaporation dynamics rather than field water-holding capacity. This study evaluated three laboratory experiments with dark chestnut soil (Haplic Kastanozem) and Ordinary Chernozem (Haplic Chernozem) represented by local light-, medium-, and heavy-loam classes. Experiment 1 compared an untreated control, SAP-P (100 mesh powder; 0.20% of dry-soil mass), agroperlite (5.0%), and their composite over a standardized 7-day interval. A randomized-block analysis across six soil-texture combinations detected a significant treatment effect (F3,15 = 12.90, p < 0.001). Fisher’s LSD separated the control from all amended treatments, while the three amendments did not differ from one another. Experiment 2 evaluated five SAP doses over a common 12-day interval. Dose responses were non-monotonic and were not significant for SAP-P, SAP-B, or SAP-G in the primary ANOVA (p = 0.155, 0.983, and 0.471, respectively); therefore, no statistically supported optimum dose was inferred. Experiment 3 found no significant particle-form effect in either light loam (p = 0.148) or heavy loam (p = 0.536). The results support a general reduction in short-term evaporation loss by the amendments in Experiment 1, but they do not identify a superior amendment, optimum SAP dose, or superior SAP particle form. Field validation is required before agricultural recommendations are made.

Agronomy doi: 10.3390/agronomy16151461

Authors: Gaoyuan Zhao Yali Zhang Hua Li Xingzao Ma Zhenhui Zheng Ming Li Kanmo Chen Jizhong Deng

Rice bacterial leaf blight (BLB), caused by the bacterium Xanthomonas oryzae pv. oryzae, severely damages leaves during rice growth, leading to reduced yield or even death. This study aimed to develop an automated identification and assessment method for rice BLB based on multispectral UAV imagery to overcome the limitations of in-field inspection methods. By obtaining multispectral image data of rice fields and extracting color features (CFs), texture features (TFs), and vegetation indices (VIs) of rice canopy using image processing techniques, three algorithms, namely, Support Vector Machine (SVM), Random Forest (RF), and Back Propagation Neural Network (BPNN), were utilized to establish a monitoring model for the severity levels of rice BLB. The classification results of several models are compared, with the overall Correct Identification Rate (CIR) of the three-feature fusion classification algorithm generally higher than the other two. Among the three algorithms, the RF algorithm performs the best, with a CIR reaching 93.4% and a Kappa coefficient of 0.91. The BPNN algorithm follows, with a CIR of 82.1% and a Kappa coefficient of 0.76, showing moderate effectiveness. Lastly, the SVM algorithm performs the poorest, with a CIR of 65.1% and a Kappa coefficient of 0.54. A rice BLB large-scale detection framework based on unmanned aerial vehicle (UAV) images was designed, and a graphical user interface (GUI) was developed using Python language to achieve automated processing from image input to final recognition results, achieving good results.

Agronomy doi: 10.3390/agronomy16151459

Authors: Ebrar Karabulut-Uzun Kübra Erkoç Spencer Barriball Bo Meyering Metin Tuna Brandon Schlautman Muhammet Şakiroğlu

Sainfoin (Onobrychis spp.) is a perennial legume forage crop valued for its adaptation to dry environments, nitrogen fixation capacity, and ecosystem service benefits. Despite its agronomic importance, broad comparative evaluations of cultivated sainfoin germplasm across environments remain limited. In this study, a diverse global panel of cultivated sainfoin germplasm representing O. arenaria, O. transcaucasica and O. viciifolia was evaluated in replicated field trials in Tekirdağ, Türkiye and Salina, Kansas, USA. Significant environmental, species, and accession effects were detected for numerous agronomic and forage-related traits, indicating substantial phenotypic diversity and strong environmental responsiveness across the evaluated germplasm. Several vegetative and forage-related traits, including stem length, forage dry matter, and canopy height, exhibited moderate to relatively high entry-mean repeatability across environments. Correlation analyses revealed strong positive associations between stem morphology traits and forage biomass production, suggesting that vegetative architecture traits may serve as useful indirect selection criteria for forage improvement. Principal Component Analysis revealed substantial phenotypic overlap among cultivated sainfoin taxa, indicating that the evaluated agronomic traits alone did not clearly separate species groups. Several plant introduction accessions performed comparably to or exceeded commercial cultivars for forage-related traits, highlighting the value of broad germplasm collections for sainfoin improvement. Collectively, these findings demonstrate that cultivated sainfoin germplasm contains substantial breeding-relevant diversity and support continued multi-environment evaluation and regionally adapted breeding strategies for perennial forage improvement.

Agronomy doi: 10.3390/agronomy16151458

Authors: Weiwei Li Xueqi Wang Jiagang Li Jiaying Sun Zhiwei Xu Yunhe Ling Bo Song Zhonghua Wang Enshi Xiao Chunlian Li Bing Jing

Silverleaf sunflower (Helianthus argophyllus Torrey and Gray) is an important salt-tolerant wild species with potential for improving cultivated sunflower, but its tolerance mechanisms remain unclear. Here, we compared the morphological, physiological, and transcriptomic responses of H. annuus and H. argophyllus under salt stress. H. argophyllus showed higher salt tolerance, which was accompanied by reduced membrane damage and better maintenance of photosynthetic performance under salt stress. This enhanced tolerance may be associated with lower stomatal density, dense trichomes, and a thick wax coating. The reference genome of cultivated sunflower (Helianthus annuus) provides limited insight into H. argophyllus because of substantial genomic variance between the two genotypes. Therefore, we generated a high-quality reference transcriptome of H. argophyllus using Iso-Seq long-read sequencing, identifying 50,153 unique genes and capturing over 91% of the gene repertoire. In total, 205 H. argophyllus-specific genes and 475 “fusion genes” were identified in the H. argophyllus transcriptome. Transcriptome profiling of leaves and roots under control and salt-stress conditions revealed upregulation of H. argophyllus-specific aquaporin genes. Commonly upregulated genes in both tissues were enriched in salt stress-responsive pathways. Genes upregulated only in the roots were more closely related to primary responses to abiotic stresses, while genes showing opposite regulation between roots and leaves reflected tissue-specific responses to salt stress. This study provides physiological, morphological, and transcriptomic insights into H. argophyllus salt tolerance and offers valuable resources for sunflower research and breeding.

Agronomy doi: 10.3390/agronomy16151457

Authors: Nail Muzafarov Maryna Kapustian Serhii Ponurenko Vilma Kemešytė Valeriya Kolomatska

Drought is a major constraint limiting maize productivity worldwide, highlighting the need for reliable methods to identify drought-tolerant genotypes. This study evaluated the effectiveness of drought tolerance indices and multivariate analyses for discriminating maize genotypes differing in drought adaptation. In total, 20 maize genotypes were assessed under optimal and water-limited conditions using grain yield under non-stress (Yp) and drought stress (Ys) together with 15 drought tolerance indices. Correlation analysis, principal component analysis (PCA), clustering, and overlay analysis were applied to identify informative indices and characterize genotype responses. Productivity-oriented indices (STI, GMP, HM, MSTI, REI, and YI) were strongly associated with grain yield and consistently identified superior genotypes, whereas SSI, TOL, and SSPI mainly reflected drought susceptibility. PCA separated productivity and stress susceptibility into two complementary components and showed that five variables (Yp, Ys, YI, ATI, and MSTI_K1) retained 99.49% of the variation explained by the complete dataset. Cluster and overlay analyses confirmed stable genotype classification and distinct adaptation strategies. These findings demonstrate that a reduced set of complementary variables provides an efficient framework for drought tolerance assessment and supports the identification of maize germplasm, combining high productivity with stable performance under variable water availability.

Agronomy doi: 10.3390/agronomy16151456

Authors: Longfei Xia Ming Jiang Siying Yang Hanyue Guo Qun Ma Jianying Qi Hua Tian Zhaowen Mo Shenggang Pan

To evaluate the yield and grain quality performance of rice varieties under rice-ratoon rice cultivation in northern Guangdong, a four-site field experiment was conducted from March to November of 2025 in Liannan and Lianshan counties of Qingyuan City and in Liucheng and Shangguan townships of Dongyuan County, Heyuan City, respectively. Seven rice varieties were evaluated: Qingxiangyou 19xiang (QXY), Nanjingxiangzhan (NJXZ), Jiangliangyouhuazhan (JLYHZ), Guiliangyou 6177 (GLY), Weiliangyouyuzhan (WLYYZ), Guiyouxinzhan (GYXZ), and Jiulixiang (JLX). The results showed clear differences in grain yield and grain quality among varieties and ecological sites. QXY generally showed the highest grain yield, especially in the ratoon crop, and ranked first in annual grain yield among the four sites, with values ranging from 10.26 to 11.63 t ha−1. However, the quality advantage differed among sites and varieties. JLYHZ showed the best quality performance in Lianshan County and Dongyuan County (Shangguan Township), GLY showed the best quality performance in Liannan County, and JLX showed the best quality performance in Dongyuan County (Liucheng Township). These results indicated a yield–quality trade-off among the tested varieties. Therefore, QXY may be considered a promising yield-oriented variety for the tested sites in northern Guangdong, whereas JLYHZ, GLY, and JLX may be more suitable where grain quality is prioritized.

Agronomy doi: 10.3390/agronomy16151455

Authors: Reta Draghici Valentina Ancuța Stoian Adina Eliza Croitoru Csaba Horvath Milica Dima Alina-Nicoleta Paraschiv Ștefan Nanu Ana-Maria Stoenescu Aurelia Diaconu Sorin Daniel Vâtcă Vlad Stoian

The study on the valorization of natural resources through cowpea cultivation represents a challenge to mitigate the negative effects of climate change on the environment and on the food security of the population in drought-affected areas globally, and specifically in the sandy soil area of Romania. Thus, the existence in Romania of an area of approximately 439,000 ha with sands and sandy soils, soils with low natural fertility (below 1.2% humus) and with deficient hydrophysical properties, implies finding solutions for their efficient valorization through ecological modeling of the species/varieties structure, depending on the adaptability of the plant in a given area. In this sense, given the economic importance of cowpea, given by the plant’s properties (drought resistance, source of increasing the organic matter content in sands, source of atmospheric nitrogen fixation, good precursor plant, source of protein for humans and animals), the cultivation of this species in a sustainable agricultural system is outlined, as an alternative solution to the cultivation of other leguminous plants. Considered a crop suitable for a climate change scenario, the conservation of genetic biodiversity and the establishment of technological inputs are essential objectives for promoting cowpea in a sustainable agricultural system, given the increasing drought in the world and the increasing need for protein.

Agronomy doi: 10.3390/agronomy16151454

Authors: Liping Wei Shunchang Su Tuanjie Zhao Fangguo Chang

Soybean pod-related traits are important for seed development, yield formation, and cultivar evaluation. However, conventional measurements are inefficient and have limited ability to characterize complex pod features such as curvature, local enlargement, and continuous color variation. In this study, mature pod images of 187 cultivated soybean accessions collected across two successive years were analyzed using a deep learning-assisted image phenotyping approach. Eight pod-related traits related to size, morphology, and color were extracted from pod images. A genome-wide association study (GWAS) was performed using 61,541 high-quality SNP markers to dissect the genetic basis of these image-derived pod traits. A total of 16 stable loci associated with pod size, morphology, and color traits were identified across 11 chromosomes. Among these loci, eight were not reported in the previous image-based soybean pod GWAS study. Based on SoyBase gene annotation and Gene Ontology biological process information, 32 biologically relevant candidate gene records were prioritized within the corresponding candidate genomic intervals, while pod-related expression profiles and SoyBase association information were used as supporting evidence for candidate gene evaluation. These findings indicate that refined image-derived traits can provide complementary genetic information beyond conventional pod measurements and offer additional opportunities for dissecting soybean pod development, morphology, and mature pod color variation.

Agronomy doi: 10.3390/agronomy16151453

Authors: Roxana Elena Călugăr Andrei Varga Carmen Daniela Vana Loredana Ancuța Ceclan Andras Fodor Alina Șimon Felicia Chețan Alexandru Costin

Maize (Zea mays L.) can be classified into several germplasm groups and crossing between these groups can produce hybrids with high heterosis. Iodent is one of the most widely used heterotic groups, both for creating new inbred lines and for developing high-performing hybrids. Thirteen inbred lines (nine Iodent and four Iodent mixed) were used as maternal parents to create new hybrids, which were tested during the 2020–2025 period at the Agricultural Research and Development Station Turda. Agronomic traits, including grain yield, the percentage of unlodged plants and dry matter content at harvest were evaluated as selection criteria to identify elite parental lines. Additionally, Principal Component Analysis (PCA) was performed as an exploratory multivariate analysis to investigate relationships among the maternal inbred lines based on grain yield, unlodged plants and dry matter. Hybrids derived from female line A452 outperformed the trial mean in all years studied, whereas those using line E390 as the female parent exceeded the average in five out of six years. PCA provided an exploratory visualization of the multivariate relationships among the evaluated maternal inbred lines.

Agronomy doi: 10.3390/agronomy16151452

Authors: Thidarat Rupngam Patchimaporn Udomkun Joachim Müller Thirasant Boonupara Puangrat Kaewlom

The timing of microbial inoculant application may influence nutrient availability, plant nutrient acquisition, and grain quality in flooded rice systems. This study investigated the effects of the application timing of a ginger-fermented microbial inoculant (GFMI) on soil and floodwater nutrient dynamics, plant performance, grain yield, and grain quality of KDML105 rice under flooded cultivation. The GFMI significantly affected soil pH, soil organic carbon (SOC), ammonium (NH4+-N), available phosphorus (P), soil MRS-culturable presumptive lactic acid bacteria (presumptive LAB) populations, and floodwater NH4+-N concentrations. Although GFMI application before plowing (GFMI-PL) maintained the highest soil presumptive LAB populations throughout the growing season, GFMI application at transplanting (GFMI-TP) produced the strongest agronomic responses. Soil NH4+-N concentrations were generally greater in GFMI-treated plots than in the non-inoculated control (CT) during the active growth period, with peak concentrations reaching 98.1 mg kg−1 under GFMI-TP compared with 76.0 mg kg−1 in the control at 69 days after transplanting. These responses were accompanied by greater shoot N, P, and K concentrations and the highest paddy rice yield (6.40 Mg ha−1), representing a 15.5% increase over the CT (5.54 Mg ha−1). GFMI-TP also produced the highest crude protein (7.62%) and crude fat (0.63%) concentrations and increased the abundance of several amino acids, particularly glutamic acid (0.61 g 100 g−1 protein), aspartic acid (0.29 g 100 g−1 protein), and proline (0.24 g 100 g−1 protein). GFMI application also influenced grain mineral composition, although responses varied among individual elements. In contrast, cooking quality characteristics were not significantly affected by treatment. Sensory evaluation indicated greater consumer preference for GFMI-treated rice, with GFMI-TP receiving the highest scores for aroma, taste/flavor, and overall acceptance. Overall, these findings demonstrate that synchronizing GFMI application with transplanting maximized the benefits of the fermented microbial inoculant, resulting in improved nutrient availability, grain yield, and grain quality in KDML105 rice under flooded cultivation. These results highlight the potential of ginger-fermented microbial inoculants as a biologically based strategy for improving nutrient management and sustainable rice production.

Agronomy doi: 10.3390/agronomy16151451

Authors: Xiaoyu Wang Ting Bao Fengbo Li Mengjie Wang Kaiyang Chen Chunchun Xu Jinfei Feng Fuping Fang

Converting conventional rice monoculture to co-culture with fish is a common strategy to increase farmers’ incomes. The Chinese soft-shell turtle is a typical high-value species for paddy co-culture, but the effects of the co-culture system (RT) on greenhouse gas emissions (GHG) are poorly understood. This study evaluated the impacts of RT on economic benefits and greenhouse gas emissions. Our results showed that RT co-culture did not significantly increase rice yield, but it provided additional income from turtle sales, increasing net profits. GHG emission responses to RT differed between the two farms. In farm 1, RT increased CH4 emissions from the rice-cultivated area but decreased them from the turtle culture area, resulting in no net effect on total CH4 emissions. The reduction of CH4 emissions in the turtle culture area was associated with lower DOC content and reduced methanogenic gene mcrA abundance. In farm 2, RT reduced CH4 emissions from both areas, lowering total CH4 emissions by 36.5%, which was linked to less water flooding and higher methanotrophic gene (pmoA) abundance. Total N2O emissions were not significantly affected by RT at either farm. RT increased indirect GHG emissions, but these accounted for only 7.2–16.9% of total emissions. Overall, RT reduced total GHG emissions by 27.7% at farm 2, with no significant change at farm 1. These findings suggest that RT can enhance economic benefit while lessening total GHG emissions.

Agronomy doi: 10.3390/agronomy16151450

Authors: Alfonso Llanderal Malena Suleika Pincay-Solorzano Said Bermúdez Stanislaus Antony Ceasar Pedro García-Caparros

Tomato production is highly affected by salt stress conditions, especially under protected cultivation systems using low-quality irrigation water. This study assessed the effects of increasing electrical conductivity (EC) levels of the nutrient solution (2, 4, 6, and 8 dS m−1) on growth, biomass distribution, RGB-based spectral indices, physiological traits, petiole sap composition, and leachate chemistry in tomato plants (Solanum lycopersicum cv. Tiny Tim) cultivated in containers within a bamboo nethouse under tropical conditions. The results obtained reported that increasing salinity significantly reduced fresh and dry biomass (61.72 and 61.55% respectively) across all plant organs, with fruits showing the highest sensitivity. Leaf area index (LAI), SPAD values, leaf nitrogen (N) concentration, leaf relative humidity (LRH), and water uptake also declined progressively under saline conditions. In contrast, root and leaf biomass allocation increased under the highest salinity level. Spectral analyses reported reductions in red and blue RGB components and normalized red and blue index values, while normalized green index increased under higher salinity levels. Petiole sap analysis showed a progressive accumulation of sodium (Na+) and chloride (Cl−) together with reductions in nitrate (NO3−-N) and potassium (K+) concentrations, particularly during the reproductive stage. In contrast, °Brix, calcium (Ca2+), and phosphorus (P) concentrations increased under salinity, particularly during the reproductive stage. Leachate analyses confirmed salt accumulation in the substrate and reduced plant water uptake. Overall, petiole sap analysis and RGB-based spectral indices provide a rapid, non-destructive, and cost-effective tool for the early detection of salinity stress in tomato, enabling timely irrigation and fertigation adjustments to improve crop performance and resource-use efficiency under saline conditions.

Agronomy doi: 10.3390/agronomy16151449

Authors: Ziling He Shouzheng Jiang Ningbo Cui Chunwei Liu Zhihui Wang Bo Liu Jing Zheng

Accurate estimation of evapotranspiration (ET) and transpiration (T) is crucial in enhancing irrigation schedules in agricultural ecosystems. A simplified canopy resistance (rsc) algorithm grounded in the Ball-Berry model was integrated into Penman–Monteith (PM)-based models and assessed in a humid-region kiwifruit orchard. The Shuttleworth–Wallace (SW) and Clumping (CL) models agreed well with eddy covariance ET (ETEC) throughout the growth season (R2 = 0.79 and 0.89, RRMSE = 0.73–0.75 and 0.22, at the sub-daily and daily scales), outperforming the Two-Patch (TP) and topography- and vegetation-based surface energy partitioning (TVET) models. SW and CL also best reproduced sap-flow-based T (TSF) (R2 = 0.72 and 0.71–0.72, RRMSE = 0.85–0.87 and 0.38–0.39), primarily due to their higher accuracy during the mid stage. In this ecosystem, canopy interception evaporation had only a limited influence on the simulation performance of the SW and CL models. ET and T were most sensitive to changes in rsc and related environmental factors, including gross primary productivity (GPP), the empirical parameter (a1), and soil water content (θ). The sensitivity of T to θ was higher during the early stage but lower during the mid and late stages due to seasonal drought. ET was more sensitive to θ than T, due to its direct effect on soil surface resistance (rss). T simulated by TP, TVET, and CL models showed greater sensitivity to leaf area index (LAI) than SW, while contrasting T and soil evaporation (E) responses to LAI caused ET to remain relatively insensitive. Both ET and T were highly sensitive to net radiation (Rn), air temperature (Ta), and vapor pressure deficit (VPD), all of which directly affect the energy balance. Overall, integrating the simplified canopy resistance algorithm with PM-based models improves ET and T estimation in humid-region orchards, supporting more efficient water management.

Agronomy doi: 10.3390/agronomy16151448

Authors: Yihang Lu Zhiyong Yu Mingxiong Ou Weidong Jia

Aiming at the low mechanization level of orchards in hilly and mountainous areas of China and the mismatch between existing walking chassis and the soft soil and complex terrain of densely planted orchards, this paper systematically conducts simulation analysis and field verification on the trafficability of an electric tracked chassis, targeting the operation demands of sandy-loam densely planted orchards in hilly regions of Jiangsu Province. Theoretical calculation yields a maximum vertical obstacle-crossing height of 0.22 m, a maximum trench-crossing width of 0.63 m, and a maximum static sliding angle of 35° for the chassis. Based on the measured bulk density and angle of repose of orchard soil, the soil contact parameters are calibrated via the Box–Behnken response surface methodology, and a RecurDyn-EDEM bidirectional coupling simulation model is established. The dynamic responses of the chassis and soil disturbance patterns are analyzed under obstacle-crossing, trench-crossing, straight-line driving, slope-climbing and steering conditions. The results indicate that the geometric trafficability of the chassis satisfies the design requirements; low-speed operation and large-radius steering can effectively reduce soil disturbance, while a 30° soft soil slope exceeds the safe trafficability limit. Field tests show that the relative errors of driving wheel torque are all below 16%, and the average straight-line driving offset rate is 1.71%, verifying the reliability of the simulation model. This study provides technical support for the performance optimization of electric tracked chassis applied in densely planted orchards of hilly areas.

Agronomy doi: 10.3390/agronomy16151447

Authors: Jinming Li Dongmei Liu Yan Ge Ruikai Zhang Jiale Zhang Xiaoming Xia

Alternaria alternata often causes preharvest potato early blight and postharvest tuber rot, which can result in substantial yield losses. Demethylation inhibitors (DMIs) are widely used to control Alternaria diseases. However, the underlying resistance risk remains poorly understood. In this study, 114 A. alternata isolates from five major potato-producing regions in Shandong, China, were evaluated for sensitivity to four DMIs (mefentrifluconazole, prothioconazole, tebuconazole, and difenoconazole). The mean EC50 values were 0.622, 6.053, 4.763, and 0.651 mg·L−1, respectively. The Shapiro–Wilk test confirmed unimodal sensitivity distributions, allowing these mean EC50 values to serve as baseline sensitivities. Two-year, two-location field trials demonstrated good control efficacy for all fungicides, with mefentrifluconazole exhibiting the highest efficacy. Three resistant mutants produced by artificial selection in the laboratory exhibited 3.78-, 28.06-, and 15.73-fold higher EC50 values and showed fitness costs, including reduced or comparable mycelial growth, sporulation, and spore germination, pathogenicity similar to that of the parental strain, and lower temperature adaptability. By establishing the first baseline sensitivity of A. alternata from potato to these four DMI fungicides and assessing the resistance risk of mefentrifluconazole, this study provides a basis for rational fungicide application, resistance management, and future field resistance monitoring.

Agronomy doi: 10.3390/agronomy16151446

Authors: Ionuț Avrămia Artur Macari Natalia Netreba Irina Dianu Iuliana Sandu Amelia Buculei Ancuţa Chetrariu Mircea Oroian Adriana Dabija

The growing interest in natural bioactive compounds has positioned sea buckthorn (Hippophae rhamnoides L.) as a source of high-value phytochemicals for pharmaceutical and functional applications. Renowned for its complex biochemical profile, this species synthesizes significant levels of lipophilic and hydrophilic antioxidants, notably carotenoids and ascorbic acid (vitamin C). These constituents provide extensive therapeutic and pharmacological benefits, including strong antioxidant, anti-inflammatory, and tissue-regenerative properties. Consequently, characterizing the exact bioactive composition of sea-buckthorn is essential for identifying cultivars with exceptional multi-functional potential. However, a major challenge in exploiting this botanical resource lies in the significant variability of its chemical profile. While the fundamental pharmacological attributes of the plant are genetically determined, the absolute concentration of its bioactive compounds can vary. Factors such as specific cultivar traits and inter-annual climatic conditions, including severe seasonal droughts, are known to influence secondary metabolite accumulation. Although individual varieties exhibit distinct nutritional profiles, systematic data tracking these fluctuations over consecutive years remain limited, particularly regarding certified cultivars adapted to specific regional ecosystems. To extend current understandings, this study evaluates the multi-functional characteristics and inter-annual stability of 17 distinct sea buckthorn varieties over a continuous three-year monitoring period. Specifically, this research focuses on four select varieties officially registered in the Republic of Moldova Official Catalogue of Plant Varieties and Species. The primary aim of this investigation is twofold: first, to quantify key quality parameters—including carotenoid levels, vitamin C content, total acidity, pH, and dry matter—across the different cultivars; and second, to determine whether genetic variety or inter-annual climatic variations exert the dominant influence on these bioactive levels over the medium term. By evaluating these parameters, this study establishes reliable baselines for selecting stable, high-yield cultivars optimized for targeted pharmacological applications.

Agronomy doi: 10.3390/agronomy16151445

Authors: Jacob J. Handel Ebony G. Murrell

Perennial grains, such as Kernza® (Thinopyrum intermedium) show promise in their ability to produce grain crops while withstanding drought and temperature extremes. However, Kernza establishes slowly, particularly in dry soils. Seed coat treatments that retain water around the germinating seed (superabsorbent polymers, or SAPs) or assist water uptake in the seedling (arbuscular mycorrhizal fungi, or AMF) could improve Kernza establishment. We conducted a greenhouse study to test the efficacy of two SAPs, one AMF inoculant (Rhizophagus intraradices), and each SAP × AMF combination as seed coats, on Kernza germination and growth under well-watered versus drought conditions. Two AMF treatments had higher proportion emergence under drought conditions than non-drought. Aboveground seedling biomass was significantly lower in four of the five seed coat treatments compared to their non-drought counterparts, but control plants did not exhibit this size reduction. Plant root colonization by AMF increased in all non-drought treatments regardless of seed coat treatment. Contrary to expectations, both SAPs tested did not improve germination and actually hindered growth under drought conditions. The AMF inoculant sometimes improved germination, but not seedling development. Future research on improving Kernza seed establishment should target more species-specific AMF inoculants or nutrient supplements as seed coats, rather than SAPs.