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Understanding how soil-plant systems regulate water use and productivity is critical for improving agricultural resilience in semiarid regions. However, the functional mechanisms linking hydrological management with rhizosphere biological processes and crop productivity remain insufficiently quantified. This study developed an integrated framework to evaluate soil-plant system functionality under ridge-furrow rainwater harvesting compacted with eco-engineered chopped straw-soil crust management. A 3-year field study was executed under randomized complete block design containing ten treatments and replicated three times. Treatments comprised three ridge widths (30 cm (W30), 45 cm (W45), and 60 cm (W60)) × three straw mulching treatments (ridges compacted with soil crust (SC0), short chopped straw-soil crust (SSC2, 2 cm), and long chopped straw-soil crust (LSC10, 10 cm)), and flat planting (FP) was control. Soil water storage, microbial biomass carbon, extracellular enzyme potential activities, nutrient availability, sainfoin water use efficiency (WUE), and fodder yield were measured to characterize hydrological, biochemical, and productivity responses. Soil health was quantified using a principal component analysis-based soil health index, while structural equation modeling identified functional pathways linking soil biological activity, water availability, and crop performance. A multi-criteria decision framework using entropy-weighted TOPSIS was applied to rank treatment performance and identify optimal management strategies. Results showed that wide ridges combined with long chopped straw-soil crust significantly enhanced soil water storage, microbial enzyme activity, and nutrient availability, resulting in improved soil health and higher WUE. Structural equation modeling revealed that ridge geometry enhanced productivity primarily through microbially mediated pathways that strengthened soil-plant functional interactions. The integrated framework explained more than 90% of yield variability and identified the 60-cm ridge width with a 10-cm chopped straw as the optimal configuration for maximizing system functionality and sainfoin productivity. These findings demonstrate that integrating hydrological management with multi-dimensional soil indicators provides a robust strategy for improving soil-plant system functionality and sustainable productivity in semiarid agroecosystems.
Rapid fruit softening, weight loss and pathogen infection induced by mechanical wound are major factors causing postharvest losses in muskmelon. As a secondary messenger, calcium can enhance plant resistance to various stresses. However, it remains unknown whether exogenous calcium affects wound healing and softening in wounded muskmelon fruit. In this study, calcium chloride (CaCl2) and ethylene glycol tetraacetic acid (EGTA) were applied to wounded muskmelon fruit, respectively. After that, all fruit were stored in darkness at 20 ± 1 °C and 85% relative humidity. The results showed that CaCl2 treatment activated phenylpropanoid metabolism related enzymes at the wound sites and promoted the accumulation of phenolic acid monomers and lignin precursors, thereby accelerating the deposition of suberin polyphenolic periderm (SPP) and lignin during wound healing. Meanwhile, CaCl2 treatment suppressed respiration rate and ethylene production, and reduced the content of total soluble solids during storage. By inhibiting the activities of cell wall-degrading enzymes, it further inhibited the degradation of cell wall components such as pectin, cellulose and hemicellulose, consequently delaying fruit softening. In contrast, EGTA treatment inhibited the deposition of SPP and lignin at the wound sites, and promoted wound ethylene production and respiration rate, and accelerated the degradation of cell wall components, thus accelerating fruit softening. In conclusion, exogenous CaCl2 treatment can effectively reduce quality deterioration during storage by accelerating the formation of wound healing structures and delaying softening in wounded muskmelon fruit. These findings offer potential application value for reducing postharvest losses of muskmelon caused by mechanical wound.
Starch represents the primary nutritional component in the cereal endosperm, typically constituting more than 80
The alpine meadows of the Qinghai-Tibet Plateau are experiencing shrub expansion, which may lead to ecosystem degradation and functional homogenization. Although previous studies have examined the mechanisms driving shrub expansion, as well as plant diversity and soil properties, the effect on soil microbial communities remain poorly understood. In this two-year field study conducted in Hongyuan County, Sichuan, we employed a paired design to compare shrub patches (SP) with meadow patches (MP). Our findings revealed that SP exhibited significantly higher soil electrical conductivity (EC, + 20.00
SlSNAT1-dependent melatonin synthesis enhances tomato cold tolerance by promoting SlNCED1-mediated ABA accumulation, thereby strengthening antioxidant capacity, maintaining photosynthesis, and reducing ROS-induced membrane damage under cold stress. Cold stress limits greenhouse tomato growth by suppressing photosynthesis, promoting reactive oxygen species (ROS) accumulation, and disrupting membrane integrity, which ultimately reduces yield. Melatonin (MT) enhances plant stress tolerance, but its role in regulating cold adaptation in tomato remains unclear. Here, we used CRISPR/Cas9-generated SlSNAT1 mutants and VIGS-mediated SlNCED1-silenced plants to test how MT influences abscisic acid (ABA) biosynthesis and cold tolerance. The SlSNAT1 mutation markedly reduced endogenous MT, decreased the expression of ABA biosynthetic genes (SlNCED1/2), and increased the expression of ABA catabolic genes (SlCYP707A1/2), thereby weakening cold-induced ABA accumulation. Accordingly, the mutants showed higher membrane permeability and ROS levels, together with lower photosynthetic efficiency and reduced antioxidant enzyme activity under cold stress. SlNCED1 silencing further reduced ABA accumulation and antioxidant capacity. By contrast, exogenous MT partly restored ABA content, antioxidant enzyme activity, and photosynthetic performance, thereby alleviating cold injury. Correlation analysis showed that ABA content was positively associated with antioxidant activity, photosynthetic traits, and osmotic regulators, but negatively associated with ROS levels and membrane damage. MT synthesis mediated by SlSNAT1 promotes ABA accumulation, at least in part, by enhancing SlNCED1 expression. These findings clarify a mechanism underlying MT–ABA cross talk during cold stress and suggest a potential strategy to enhance cold tolerance in greenhouse tomato.
