Crops, Volume 6, Issue 3 (June 2026) – 12 articles

Legume cultivation offers a chance for agricultural development on lands that have been abandoned over the years. In this study, simple agronomic indicators on the growth and yield of faba bean (Vicia faba L.), pea (Pisum sativum L.), and white lupin (Lupinus albus L.) were assessed on the abandoned agricultural lands of Foloi Plateau in Western Greece. Field trials were conducted from October 2023 to July 2025, and the legumes were grown either according to the false seedbed concept or with conventional seedbed preparation practices (direct sowing). The false seedbed involves pre-sowing weed control following initial seedbed preparation, and in these trials, it suppressed weed density by 62–77%. The Normalized Difference Vegetation Index (NDVI) of faba bean and pea increased by 13% on the false seedbed plots, while white lupin NDVI was not affected by treatments (p ≥ 0.05). Destructive crop biomass measurements were in accordance with NDVI assessments. Faba bean and pea seed yield demonstrated an increase of 17% and 23%, respectively, in the false seedbed plots compared to direct sowing plots. White lupin seed yield was not significantly affected by false seedbed (p ≥ 0.05). This study provides preliminary evidence supporting the use of legume crops as a component of sustainable agricultural revitalization in the Foloi region. However, further research is required to optimize legume cultivation on the abandoned lands of the wider region as a first step towards the agricultural revitalization in the Plateau. Full article

We evaluated a multi-output neural network framework for jointly analyzing maize grain yield (GY) and root lodging percentage (LP) using above-ground morphological traits measured under defined environmental conditions. To address model robustness, the multi-output neural network was compared with linear regression, elastic net, random forest, and XGBoost using repeated five-fold cross-validation, an 80/20 holdout split, and independent year-wise validation. Under repeated cross-validation, XGBoost provided the strongest average predictive performance for both traits, with R² values of 0.57 for GY and 0.67 for LP. The multi-output neural network showed moderate performance, with R² values of 0.49 for GY and 0.57 for LP. Final holdout performance for the neural network for GY and LP was R² = 0.64 and R² = 0.92, respectively. Year-wise validation showed weak temporal transferability because the two seasons differed not only in environmental conditions, but also in lodging mechanism. Repeated permutation importance identified ear width (EW), kernel row number (RNE), thousand kernel mass (KM1000), and kernel number per ear (KNE) as important predictors of GY, while LP prediction was most strongly associated with internode major diameter (IDmajor), ear length (EL), and the number of green leaves (NGL). Across both permutation importance and SHAP, only RNE and NGL were consistently shared between GY and LP. Supplementary ALE diagnostics indicated that RNE showed increasing model-estimated effects for both predicted GY and LP, whereas NGL showed a positive association with predicted GY but a decreasing or nonlinear association with predicted LP. These results show that joint modeling can support exploratory trait interpretation, but the predictive relationships remain environment-specific and should not be interpreted as causal or broadly transferable without further multi-environment validation. Full article

This study investigated the epidemiology and incidence of citrus Huanglongbing (HLB) disease in citron (Citrus medica L.) under varying field conditions. This research specifically aimed to quantify disease severity, assess populations of the primary vector, the Asian citrus psyllid (Diaphorina citri), and identify potential alternative host plants sustaining the vector and the pathogen. Field surveys were executed across three sites characterised by distinct elevations and management practices. Site-level soil nutrient profiles exhibited moderate acidity (pH 4.67–5.74) and significant differences in organic matter and nitrogen. These findings suggest that localised deficiencies in calcium and boron may exacerbate disease severity, contributing to the varied epidemiological patterns observed across sites. Analysis revealed that both HLB disease severity and D. citri population density were significantly influenced by altitude, field condition, and orchard management. The low-elevation site (860 m above sea level (ASL)), characterised by poor maintenance, exhibited the highest mean psyllid populations (averaging 13 individuals per sticky trap per day) and the most severe disease symptoms. Conversely, the high-elevation site (1674 m ASL) displayed significantly lower infection rates and healthier tree conditions. Symptomatic citron trees across all sites consistently exhibited characteristic HLB foliar and fruit symptoms (blotchy mottle and lopsided fruits). Quantitative Polymerase Chain Reaction (qPCR) successfully detected the causal agent, Candidatus Liberibacter asiaticus (CLas), in symptomatic citron samples from all locations, with the highest relative fold-change (2^−ΔΔCt = 4628.24). Crucially, multiple developmental stages of D. citri were observed infesting the common weed Bidens pilosa. Furthermore, qPCR confirmed the presence of CLas DNA within the B. pilosa tissue itself (2^−ΔΔCt = 210.84). This finding constitutes the first field-based evidence that B. pilosa can serve as a novel alternative host that supports both the D. citri vector and the CLas pathogen. These results establish citron as a highly susceptible host and identify B. pilosa as a new, critical epidemiological link in the HLB transmission cycle, thereby underscoring the necessity for integrated, landscape-level disease management strategies. Full article

This study investigated the vigor and molecular responses of soybean (Glycine max) seedlings belonging to cultivars from various maturity groups under simulated abiotic stress. Seeds and seedlings were subjected to varying concentrations of NaCl (150–300 mM) and PEG-6000 (20–30%), during long-term (12 days) and short-term (72 h) treatments, to evaluate the impact of salinity and drought on seedling viability and gene expression. Molecular analysis via qRT-PCR focused on the transcriptional profiles of the auxin transmembrane influx carrier LAX6, the vacuolar pyrophosphatase H⁺-PP-ase, and the stress protein kinase StrK2. The data indicated a dose-dependent correlation between stress intensity and developmental inhibition; increased concentrations of stress agents generally resulted in delayed germination and reduced survival rates. Certain soybean genotypes exhibited a robust transcriptional response, characterized by a several-fold increase in the expression of all studied genes following stress induction. These findings suggest that soybean abiotic stress responses may be influenced by a complex interaction between stress severity, exposure duration, genotype specificity and the maturity group. Full article

Improving the productivity and stability of winter wheat under increasingly variable climatic conditions remains a major challenge for sustainable agriculture. This study evaluated the effects of pre-sowing seed treatment with a microbial preparation (Nando BioExpert) and a biostimulant (Vitazyme), applied individually and in combination, on crop establishment, yield components, and grain yield of winter wheat under unstable moisture conditions in the Right-Bank Forest-Steppe of Ukraine. A three-year field experiment demonstrated that both treatments positively influenced plant growth, while their combined application produced a pronounced synergistic effect. Seed treatment enhanced plant establishment, increasing plant density at emergence from 242 plants m⁻² in the control to 372 plants m⁻² under the combined treatment. This improvement contributed to increased stand-level productive tiller density per unit area. Consequently, grain yield was consistently improved across years, with the combined treatment producing the highest average yield (6.04 t ha⁻¹), corresponding to a 37% increase relative to the control. The results indicate enhanced winter wheat resilience to environmental stress under biological seed treatment. Overall, integrating microbial inoculants with biostimulants represents an effective strategy for improving winter wheat productivity under moisture-limited conditions and supports the transition toward sustainable and resource-efficient crop production systems. Full article

Potatoes are a crop of great importance for global food security, and their industrialization requires certain postharvest quality characteristics that are affected by cultivation practices. Unlike previous studies that focused on single agronomic factors or genotype effects, to increase knowledge, this work evaluates the interaction between planting method (bag vs. soil) and cultivation condition (greenhouse vs. open field) on postharvest and frying quality of the high-altitude variety ‘Diacol Capiro’. A completely randomized design was used with four treatments arranged in a 2 × 2 factorial layout, where the first factor was the planting method (in bags or in soil) and the second factor was the cultivation conditions (in a greenhouse or in an open field). Tubers grown in a greenhouse, especially with planting in bags, showed greater starch retention, higher firmness, lower soluble solids content, and less mass loss during storage. The starch content varied significantly among treatments, reaching a maximum of 6.9% after 35 days of storage. The specific gravity of the fried potatoes was higher in greenhouse-grown tubers (1.080) than in those planted in the open field (1.070), with values close to the industrial standard (>1.080). The skin luminosity decreased by 16.2% during storage, while the b* parameter of the flesh (yellow color) was higher in tubers from greenhouse planting. Overall, ‘Diacol Capiro’ tubers grown in a greenhouse with planting in bags showed better postharvest attributes and greater potential for frying quality. Full article

Potatoes (Solanum tuberosum L.) contain a diverse range of primary and secondary metabolites that determine their nutritional, storage, and defense characteristics. There has been an increasing number of metabolomics-based studies in potato breeding and stress assessments recently; however, there remains a lack of comprehensive studies addressing metabolite variation using multiple analytical techniques. Metabolomics offers valuable insights into these variations by enabling the identification of key metabolic markers, and the combined use of multiple analytical techniques on the same sample allows for broader metabolite coverage. This review provides an integrated understanding of how primary and secondary metabolism is influenced by environmental and developmental conditions across potato organs as characterized by various analytical techniques. Unlike existing reviews, this manuscript provides a critical evaluation of studies examining the effects of cultivation systems and potato plant developmental stages on primary metabolites across different organs while also emphasizing the role of newly characterized secondary metabolites in stress responses and offering a comparative assessment of extraction techniques. Metabolomic approaches assess the combined effects of multiple intrinsic and extrinsic factors, and through the integration of multi-omics datasets, enabled by the rapid advancement of bioinformatics tools, they enhance our understanding of potato physiology and support improved crop management and breeding strategies. Full article

Rice straw mulching is a soil management practice that influences soil microbial communities. However, its effects on nematode communities under upland rice systems in salt-affected soils remain unclear. This study examined nematode community responses to rice straw mulching at rates of 0, 3.5, 7.0, and 10.5 t ha⁻¹ in paddy fields at two sites, Lieu Tu and Long Phu, in Soc Trang Province, Mekong Delta, Vietnam. A total of 37 and 35 nematode genera were identified in Lieu Tu and Long Phu, respectively. Bacterivores were the dominant group, followed by herbivores. Acrobeloides, Hirschmanniella, Chronogaster, Aporcelaimellus, and Prismatolaimus were prevalent in Long Phu, while Acrobeloides, Prismatolaimus, Hirschmanniella, and Alaimus dominated in Lieu Tu. The highest mulching rate (10.5 t ha⁻¹) increased total nematode abundance, particularly cp1 and cp2 groups in Long Phu, while the application of 7.0 t ha⁻¹ increased the proportion of omnivorous feeders in Lieu Tu. Mulching increased total nematode biomass and metabolic footprints, indicating improved soil fertility. At Long Phu, mulching also increased biodiversity, as reflected by the higher species richness and Shannon–Wiener indices. The highest mulching application rate (10.5 t ha⁻¹) increased the relative abundance of cp2 functional guilds at both sites. Mulching reduced the relative abundance of plant-parasitic nematodes at both sites, and increased cowpea yield from 5.1 to 13.9 t ha⁻¹ and 5.67 to 9.70 t ha⁻¹ at Lieu Tu and Long Phu, respectively. These findings suggest that the rice straw mulching at 10.5 t ha⁻¹ improves soil structure and nematode diversity, thereby supporting agricultural sustainability in salt-affected soils under climate change conditions. Full article

The increasing pressure on water resources has stimulated the use of treated wastewater in agricultural irrigation, although its effects on plant development remain uncertain. This study evaluated the effects of wastewater treatments and irrigation depths on the morphophysiological development of lettuce (Lactuca sativa L.). A split-plot experiment was conducted with crop cycles in the main plots and a factorial arrangement in the subplots, consisting of five water sources and five irrigation depths (50% to 150% ETc), with three replications. Seven variables were evaluated, including growth traits and water productivity. Irrigation depth significantly affected all variables (p ≤ 0.01) and was the main driver of vegetative growth, increasing shoot fresh mass, stem diameter, and plant height. In contrast, water sources showed smaller effects. Water productivity decreased with increasing irrigation depth and showed weak correlations with other variables (r ≤ 0.468). Machine learning models achieved moderate accuracy for irrigation depth prediction (≈55%), with confusion among adjacent classes, indicating detection of a gradient rather than precise classification. Prediction of water sources was low (<30%), confirming limited morphological differentiation. Plant height and stem diameter were the most informative variables. These results indicate that irrigation management has a stronger influence on lettuce growth than water source. Full article

The increasing need to reduce agrochemicals has intensified the search for sustainable alternatives in crop production. Insect frass, a by-product of insect rearing, has recently emerged as a promising organic fertilizer. In the present study, the effects of Tenebrio molitor frass (TMF) on plant growth and productivity were evaluated in three vegetable crops, cucumber (cv. Aisopos), pepper (cv. Lamuyo), and lettuce (cv. Paris Island), under greenhouse conditions. Experimental plants were grown in pots under two substrate fertility levels (fertilized and non-fertilized peat, hereafter referred to as “rich” and “poor” soil) and received TMF at two rates (1% and 2% w/w), applied either once or twice. Plant height and weight, fruit number and weight, and total production per plant were recorded. TMF application, applied as a soil amendment, enhanced plant growth and yield of the treated plants compared to the control, although the magnitude and consistency of the response varied among crops, soil types, and measured parameters. A clear dose-dependent response was not observed, as the 2% rate did not consistently outperform the 1% rate. Likewise, splitting the same total amount of TMF into two applications did not significantly improve plant performance. The response to the TMF application varied among crops in terms of growth and yield parameters. Lettuce recorded the strongest response, while cucumber and pepper exhibited more moderate improvements. Notably, TMF significantly increased growth and productivity even at the lowest application rates under poor soil conditions. These findings demonstrate that TMF is a promising low-input organic fertilizer under the tested conditions and highlight the importance of optimizing application rate and strategy for sustainable vegetable production. Full article

Coffee plantations are highly vulnerable to climatic factors. In this regard, the vulnerability of coffee agroecosystems to extreme hydrometeorological events has been underexplored. This research proposes a method to assess coffee plantations’ vulnerability to five phenomena that have led to disaster declarations in the municipalities where they are cultivated: extreme rainfall, tropical cyclones, floods, snow and low temperatures, and drought. This study considered coffee production, local climate information, hydrometeorological records, and environmental protection actions, spanning 22 years in the eastern state of Veracruz, Mexico. All data were normalized and evaluated for three production values: harvested area ratio, yield, and volume. The Exposition accounted for the number of events, correlating production data with phenomena to assess sensitivity, while the adaptive capacity was assessed by considering environmental protection actions. The results indicated that the most frequent phenomena were extreme rainfall, followed by tropical cyclones, snow and low temperatures, droughts, and floods. However, tropical cyclones accounted for the highest number of vulnerabilities, and drought caused the highest level of vulnerabilities. Snow and cold temperatures reduced vulnerabilities, and floods have non-statistical effects. In general, coffee agroecosystems have a low vulnerability index (6.21 on a scale of 15) due to their location within the local forest. Full article

Research has advanced in the development of precision seed metering devices to ensure proper seed distribution at high speeds. However, little is known about the effect of increasing seeding speed, as well as seeding at different inclinations of the tractor-seeder unit, on the integrity and physiological quality of soybean seeds. This study aimed to identify the effect of travel speeds (5, 7, 9, 11, and 13 km h⁻¹) combined with three longitudinal inclinations of a pneumatic seed metering device (−11°, 0°, and 11°), simulating field conditions, on the distribution and integrity of soybean seeds. We used a 5 × 3 factorial design was used with an additional control treatment in which the seeds did not pass through the metering device. The variables evaluated included the percentage of spacing between individual seeds, germination, mechanical damage (tetrazolium test), and seedling emergence. The results demonstrated that increasing the speed did not prevent the spacing between individual seeds from falling below the minimum limit of 90% for pneumatic seed metering devices. The treatments did not affect germination compared to the control. Sowing on a slope caused the greatest mechanical damage to soybean seeds. All treatments significantly reduced plant emergence, except when the pneumatic metering device operated at an incline of 0° at 9 km h⁻¹. Full article