Search Results (2,980)

Drought stress significantly constrains broccoli (Brassica oleracea L.) productivity by impairing growth, photosynthesis, and yield. Seed priming with ascorbic acid (AsA) has shown promise in enhancing early seedling performance; however, its effects on head development and yield under water deficit remain limited. This greenhouse pot experiment evaluated four seed treatments: non-primed control, water-primed control, 1 mg L⁻¹ AsA, and 10 mg L⁻¹ AsA under two irrigation regimes: 100% and 50% field capacity. Growth, physiological traits, biochemical responses, and yield were assessed. AsA priming significantly (p < 0.05) enhanced plant height, net photosynthesis, and chlorophyll content under both water regimes. Under 100% FC, water priming significantly increased canopy length, whereas under 50% FC, only AsA priming produced a significant increase relative to the non-primed control (p < 0.05). Biochemical responses further showed that 10 mg L⁻¹ AsA significantly (p < 0.05) increased chlorophyll a and chlorophyll b under 50% FC compared with the non-primed control. Proline accumulation was reduced by 10 mg L⁻¹ AsA, but this reduction was significant (p < 0.05) only under 100% FC. Under 100% FC, 10 mg L⁻¹ AsA significantly (p < 0.05) increased total phenolic content compared with the non-primed control. Total flavonoid content was significantly (p < 0.05) increased by 1 and 10 mg L⁻¹ AsA compared with the control, while both water priming and AsA priming significantly (p < 0.05) increased carotenoid content and reduced H₂O₂ accumulation relative to the non-primed control, irrespective of watering regime. Total yield per plant, measured on a fresh weight basis, significantly (p < 0.05) increased with increasing AsA concentration, with 10 mg L⁻¹ AsA enhancing yield by 37.8% relative to the water-primed control and by 70.5% relative to the non-primed control, independent of water regime. Percentage dry weight was unaffected by AsA treatment. Overall, AsA seed priming potentially enhanced physiological resilience and fresh yield of broccoli under water-limited conditions, indicating its potential as a low-cost strategy for drought mitigation. Full article

Sweet sorghum is a promising crop for bioethanol production in semi-arid regions, due to its tolerance to drought and salinity, where conventional energy crops face limitations. This study aimed to evaluate the agronomic performance of sweet sorghum irrigated with treated domestic wastewater (TDW) and its application as a substrate for bioethanol production under high-gravity (HG) and very-high-gravity (VHG) fermentation conditions. Field experiments were conducted in the Brazilian semi-arid using a 5 × 5 full factorial design consisting of five irrigation depths (40–160% crop evapotranspiration, ETc) combined with five potassium fertilization doses (0–80 kg·ha⁻¹), totaling 25 treatments. Agronomic performance, biomass production, and total reducing sugar accumulation were evaluated in both plant cane and ratoon crops. Sweet sorghum juice was subsequently combined with sugarcane molasses and fermented using Saccharomyces cerevisiae in batch and fed-batch processes. Irrigation with TDW associated with moderate potassium fertilization enhanced plant development, biomass yield, and sugar accumulation, particularly at irrigation depths between 100% and 130% of ETc, reaching up to 1908 kg·ha⁻¹ of TRS. Bioethanol production achieved fermentation efficiencies of 91.83% and 84.80% and productivities of 4.63 and 4.21 g·L⁻¹·h⁻¹ under HG and VHG conditions, respectively. These findings indicate that sweet sorghum irrigated with TDW is a promising feedstock for bioethanol production under high-gravity fermentation conditions while supporting the use of alternative water resources in semi-arid environments. Full article

Drought represents one of the major constraints limiting maize productivity in southeastern Europe, particularly under non-irrigated conditions. This study evaluated the effectiveness of foliar biostimulants derived from animal collagen and keratin hydrolysates in mitigating drought stress and improving maize performance in southern Romania during a six-year field experiment (2020–2025). During the screening phase (2020–2022), four formulations (FM1, FM2, KC, and K2) were applied at two rates (5 and 10 L ha⁻¹) and compared with an untreated control. Significant effects of biostimulant formulation and dose were identified for plant height and grain yield (p < 0.001). Duncan’s multiple range test showed that K2 applied at 10 L ha⁻¹ achieved the highest mean grain yield (87.71 q ha⁻¹), significantly exceeding the untreated control (70.94 q ha⁻¹). Based on these results, K2 was selected for long-term validation during 2023–2025 and subsequently evaluated across the entire six-year experimental period. Mean grain yield increased from 52.06 q ha⁻¹ in the untreated control to 58.74 and 64.91 q ha⁻¹ following K2 application at 5 and 10 L ha⁻¹, respectively. Yield improvements were particularly pronounced during years characterized by severe precipitation deficits, when relative yield increases reached up to 41.9%. Economic analysis demonstrated positive net returns in all experimental years, with average profits of 108.6 EUR ha⁻¹ and 206.9 EUR ha⁻¹ for the 5 and 10 L ha⁻¹ application rates, respectively. The results demonstrate that keratin-based biostimulants derived from industrial by-products can improve maize productivity, enhance drought resilience, and contribute to circular-economy approaches in sustainable agriculture. Full article

This study investigated alternative pathways involving adaptive traits associated with drought tolerance in popcorn cultivated under soil water restriction through path analysis. Direct and indirect effects were estimated for morpho-agronomic variables, including ear height (EH), grain number per ear (GNE), grain number per row (GNR), 100-grain weight, grain yield (GY), and popping expansion (PE); physiological variables, such as relative chlorophyll content, anthocyanin and flavonoid indices, and maximum quantum efficiency of photosystem II; and root-related traits, including brace- and crown-root number and root angle. Fifty popcorn inbred lines were assessed under contrasting water conditions (WC), namely well-watered and water-stressed environments, during two crop seasons (CS). Water restriction was imposed before male anthesis, and the permanent wilting point was reached at 63 days after sowing in CS-2020 and at 100 days in CS-2021. Significant genotype × WC × CS interactions were identified for all evaluated traits. The effects of drought varied according to the developmental stage at which stress occurred. Under both water regimes, indirect selection through EH and GNR favored gains in GY, whereas EH and GNE showed the strongest indirect contributions to PE. Among the evaluated variables, EH emerged as a promising trait for indirect selection in popcorn breeding under water-limited conditions. Full article

Trehalose-6-phosphate (T6P) is involved in the regulation of plant growth and stress-related responses; however, its potential role in post-drought recovery remains unclear in legume crops. This study evaluated whether foliar application of native T6P could improve growth, yield formation, and physiological recovery in adzuki bean after pre-flowering drought stress. We aimed to propose a model for the production and drought tolerance regulation in adzuki bean. A three-year field experiment was conducted by applying T6P at both the budding stage and the initial pod stage. The plant architecture, yield, photosynthetic characteristics, defensive enzyme activity, sugar metabolism and hormone changes were evaluated. The results indicated that T6P significantly increased root, stem and leaf parameters in adzuki bean it also increased all yield traits except for the main stem branches and sections during post-drought recovery. Indeed, the yield per block of 5μM and 10μM of T6P application during post-drought recovery increased by 20.66% and 31.60% on average compared to the control under well-watered conditions and by 47.68% and 60.20% under drought stress during the three experimental years. Foliar T6P treatment was associated with higher antioxidant enzyme activities and related gene expression, lower ROS accumulation and proline content, and changes in sugar- and hormone-related traits during post-drought recovery. Therefore, foliar application of T6P at the budding and initial pod stages improved growth, yield formation, and post-drought recovery in adzuki bean. The result provide a novel strategy for T6P application for coordinating the high production potential and crop resilience. Full article

Maize (Zea mays L.), a critical global food crop, suffers severe yield losses from drought and salt stresses. Xyloglucan endotransglucosylase/hydrolases (XTHs) are cell wall-modifying enzymes regulating plant growth and abiotic stress responses, but the role of -ZmXTH23 in drought and salt tolerance remains unclear. Here, we heterologously expressed ZmXTH23 in Nicotiana benthamiana (N. benthamiana) and confirmed its extracellular localization. ZmXTH23-overexpressing (OE) lines showed significantly increased plant height, root length, and shoot fresh weight under normal conditions. Under 350 mM NaCl or drought stress, the OE lines exhibited enhanced tolerance, with less leaf wilting, higher biomass, and larger leaf area. Physiologically, the OE lines had higher peroxidase (POD) and superoxide dismutase (SOD) activities and relative water content (RWC), but lower malondialdehyde (MDA) content. Additionally, OE seeds maintained ≥50% germination under 120 mM NaCl (WT: 0%) and nearly 100% under 200 mM mannitol. ZmXTH23 improves drought and salt tolerance in N. benthamiana by upregulating antioxidant enzymes and enhancing water retention, making it a promising candidate for maize stress-resistance breeding. Full article

Standardized drought indices such as the Standardized Precipitation Index (SPI) are widely used in both monitoring and climate-change impact assessments. However, SPI values are not uniquely defined unless the reference climatology used for standardization is explicitly stated and justified−a methodological issue that becomes critical under non-stationary climate conditions. Here, we present a methodological assessment of how reference-climatology strategy affects SPI-based drought projections under climate change, using Türkiye’s 26 major basins as a hydroclimatically diverse testbed. These assessments inform sustainable water resources planning, agricultural adaptation, and climate-resilient infrastructure design under non-stationary climate. Daily precipitation projections from 56 GCM-RCM pairs (EURO-CORDEX EUR-11, 0.11° (approximately 12 km at the mid-latitudes of the study domain); CMIP5 RCP8.5) were bias-corrected against ERA5-Land and aggregated to basin means. We computed SPI-9 and compared two commonly used reference strategies: (i) a fixed historical baseline (1970–2005), applied consistently to both historical and future periods (fixed-baseline SPI); and (ii) a period-specific baseline (period-specific SPI; future SPI values are standardized to the climatology of the future evaluation period itself). Using the same climate simulations, the two strategies yield markedly different drought projections. At the country scale, end-of-century drought time reaches 458 months under the fixed-baseline strategy, whereas the period-specific strategy indicates 393 drought months. Corresponding severity summaries are likewise stronger under fixed-baseline standardization. The contrast is even stronger in several Mediterranean basins, where fixed-baseline standardization produces persistently severe drought conditions. These results show that SPI-based drought projections are substantially sensitive to the choice of reference-climatology strategy, and that the same climate ensemble can support materially different drought narratives depending on how anomalies are standardized. Because the two strategies differ in both reference-timing and calibration-window length (36 versus 95 years), the headline contrast should be interpreted as a combined effect rather than as a pure baseline-timing result. In the present implementation, the period-specific strategy uses a single future calibration period (2006–2100), so the comparison should be interpreted as a stress test of reference framing under non-stationary climate rather than as an equal-length baseline experiment. An equal-length late-baseline sensitivity check (1970–2005 versus 2065–2100; both spanning 36 years) shows that the fixed-to-late-baseline contrast is larger than the fixed-to-period-specific contrast in 25 of 27 spatial units, including a 3.0-fold amplification at the national scale, indicating that the reference-timing effect persists when calibration-window length is held constant. Because the analysis is based on a CMIP5-driven RCP8.5 ensemble, the numerical projections should be interpreted as a high-end stress-test envelope rather than as the most likely outcome. We therefore recommend that drought projection studies explicitly report the reference-climatology strategy, justify the calibration window, and distinguish between analyses designed to quantify change relative to a historical climate and analyses designed to describe anomalies relative to an evolving future climate. These methodological choices have direct implications for sustainable water resources management and drought-risk preparedness in water-stressed Mediterranean systems, and contribute to broader sustainability targets such as Sustainable Development Goal 6 (Clean Water and Sanitation), SDG 13 (Climate Action), and SDG 15 (Life on Land). Full article

Drought stress severely limits the growth, yield, and seed quality of rapeseed. Plant U-box (PUB) proteins are a class of E3 ubiquitin ligases involved in abiotic stress responses, but the function of BnPUBs in B. napus drought tolerance remains largely unknown. We obtained bnpub12 knockout mutants by CRISPR/Cas9 technology, and constructed BnPUB12 overexpression lines. This study investigated the role of BnPUB12 in drought resistance through phenotypic, physiological, and biochemical analyses. Under drought stress, bnpub12 mutants exhibited a significantly lower survival rate during germination, whereas overexpression lines showed a higher survival rate. During the seedling stage, bnpub12 mutants displayed lower relative water content, a lower water holding capacity, and a faster water loss rate; conversely, overexpression lines showed higher relative water content, an enhanced water holding capacity, and a slower water loss rate. DAB and NBT staining revealed less reactive oxygen species accumulation in overexpression lines but stronger staining in mutants. Physiological measurements further indicated that BnPUB12 overexpression increased SOD and POD activities and proline content, while decreasing MDA content; the opposite trends were observed in mutants. Overall, these results demonstrated that BnPUB12 positively regulates drought tolerance in B. napus during both the germination and seedling stages. Full article

Increasingly frequent and severe drought events restrict global agricultural productivity. As sessile organisms, cereal crops have evolved phenotypic plasticity, drawing on drought escape (DE) and drought avoidance (DA) strategies to balance survival and reproduction. While the mechanisms governing photoperiodic flowering and drought responses are well characterized individually, their molecular intersection remains poorly understood. This review summarizes recent advances in the crosstalk between these two pathways. We highlight the divergent roles of core genetic hubs, such as florigen regulation, GIGANTEA (GI), DELLA proteins, and dual-function transcription factors (e.g., ZmCCT, Ghd7, Ppd-H1), and the breeding-selected alleles, including Green Revolution variants, that can partly uncouple stress tolerance from developmental penalties, though trade-offs often remain. Furthermore, we examine the internal networks driving this crosstalk, including circadian clock phase shifts, sugar and energy signaling through the trehalose-6-phosphate (T6P)-SNF1-related protein kinase 1 (SnRK1) module, and the antagonistic balance within phytohormone networks centered on abscisic acid (ABA). Finally, we propose that integrating epigenetic stress memory, systemic root-to-shoot signaling, and targeted CRISPR/Cas promoter engineering provides a useful conceptual framework for breeding climate-resilient, yield-stable crops. Full article

Climate change is increasingly constraining agricultural productivity by intensifying drought, accelerating soil degradation, and increasing pest and disease pressure. In this context, biostimulants are emerging as sustainable tools to improve crop resilience and maintain yield under suboptimal conditions. This study evaluated the effects of microbial and non-microbial biostimulants on chickpea (Cicer arietinum L.) growth, grain yield, seed quality, root traits, and soil properties under low-fertility and water-limited conditions in a marginal field in southern Italy. Treatments included an untreated control and biostimulants based on microelements, arbuscular mycorrhizal fungi (AMF), microbial consortia, ozonated oil, and humic substances. Biostimulants significantly affected agronomic traits. Humic substances increased plant height, while microelements markedly enhanced reproductive performance, with pod number increasing from 13 in the control to 23 pods plant⁻¹. Root traits were also improved, particularly under microbial, humic, and AMF treatments. Grain yield was highest in the ozonated oil treatment (430.6 kg ha⁻¹), whereas seed nutritional composition showed only limited variation among treatments. Biostimulants also induced treatment-specific changes in soil fertility indicators. Overall, the results indicate that selected biostimulants can improve chickpea performance and modulate soil fertility under marginal conditions, although multi-year studies are needed to confirm the stability of these responses under variable environments. Full article

Cucumber (Cucumis sativus L.) is an economically important vegetable crop worldwide, but its yield and quality improvement are often constrained by drought stress. To investigate the physiological and molecular mechanisms by which exogenous allantoin enhances drought tolerance in cucumber, cucumber seedlings were sprayed with 6 mM allantoin solution once (A1), three times (A3), or five times (A5), while control plants were sprayed with distilled water (CK1, CK3, CK5). Each treatment consisted of three biological replicates. After treatment, drought stress was simulated by irrigating with 20% polyethylene glycol 6000 (PEG-6000) solution. The results showed that the protective effect of exogenous allantoin against drought stress was cumulative. After five applications (A5), the net photosynthetic rate (Pn) and water-use efficiency (WUE) of the plants were significantly higher than those of the corresponding control (CK5) (p < 0.01). The detached leaf water loss rate progressively decreased with an increasing number of allantoin applications, while the total leaf wax content increased approximately 2-fold (p < 0.01). Measurements of wax content in different plant tissues indicated that allantoin mainly induced wax accumulation in aboveground organs (leaf, stem, and fruit epidermis), and this effect was validated in three commercial varieties. Integrated transcriptomic and metabolomic analyses revealed that the cucumber CsCER1 gene (encoding a very-long-chain aldehyde decarbonylase) is a core allantoin-responsive gene. After silencing CsCER1 using virus-induced gene silencing (VIGS), the allantoin-induced wax accumulation and drought tolerance were almost completely lost: the wilting severity and detached leaf water loss rate of the silenced plants were comparable to those of the empty vector control, and no significant increase in wax content was observed. This study reveals a novel mechanism by which exogenous allantoin enhances drought tolerance in cucumber through activating CsCER1-mediated cuticular wax synthesis, providing a theoretical basis for the chemical regulation of drought tolerance in cucurbit crops. Full article

Rice, a staple food for over half of the global population, faces significant threats from environmental stressors such as heavy metal (HMs) contamination, notably cadmium (Cd) and arsenic (As), and increasing drought severity, exacerbated by climate change. These challenges not only compromise rice yield and quality but also pose serious food safety risks due to HM accumulation in grains, endangering human health. Modified biochar (MBC), a carbon-rich material derived from the pyrolysis of organic matter with post-treatment enhancements, has emerged as a strategy to address these dual stressors. MBC application (typically 5–20 t ha⁻¹) reduces Cd and As bioavailability in paddy soils by 40–60% and decreases metal accumulation in rice grains by 20–85% compared to the control. Under drought conditions, MBC improves soil water-holding capacity by 11–45% and enhances crop water use efficiency by 15–24%, leading to yield improvements of 20–50% under moderate water deficit. Furthermore, MBC supports nutrient availability, fosters robust root systems, and enhances soil aeration, collectively improving rice growth under adverse conditions. Beyond its agronomic benefits, MBC provides a framework for addressing multiple challenges by integrating scientific innovation, policy alignment, and community participation. This approach not only reduces heavy metal toxicity and strengthens plant resilience but also enhances food security and advances Sustainable Development Goals (SDGs 2, 3, 4, 12, 13, 15, 17). By promoting environmentally sustainable agriculture and contributing to climate change mitigation, MBC represents a transformative tool for ensuring sustainable rice production in the face of global challenges. Full article

To address yield uncertainties from contrasting hydrothermal events in black soil regions, this study developed a universal estimation framework integrating multi-dimensional features. The universal yield estimation framework leveraged data from contrasting flood (2024) and drought (2025) scenarios in Youyi Farm in the Northeast Black Soil Region. And we fused multi-dimensional environmental features, including remote sensing, soil, and micro-topography factors, to identify “Regime Shifts” in yield-driving mechanisms across contrasting years. We evaluated four ML algorithms (RF, XGBoost, MLP, and TabNet) using Recursive Feature Elimination with Cross-Validation (RFECV) for variable optimization. Results showed the following: (1) The Universal RF model achieved superior robustness (R² = 0.80), overcoming inter-annual fluctuations. (2) Mechanistic analysis identified a “Regime Shift” in yield drivers, transitioning from micro-topography-governed “drainage limitation” during flooding to soil-texture-dominant (SAND) “linear limitation” during drought. (3) Dynamic growth-stage differential features successfully corrected asymmetric spectral responses, resolving slope inversion and overestimation driven by “non-productive greenness” during flooding. (4) Spatio-temporal yield mapping revealed a transition from topography-constrained linear distributions (2024) to soil-moisture-driven “patchy mosaic” structures (2025). Moran’s I increased from 0.21 to 0.45, reflecting intensified yield clustering and intensified spatial clustering under drought. This study provides a robust tool for food security monitoring and site-specific management in climate-vulnerable intensive agricultural zones. Full article

Drought is one of the major abiotic stress factors limiting crop yield and quality, posing a significant threat to sensitive species like cucumber (Cucumis sativus L.). This study evaluated the potential of bitter melon (Momordica charantia cv. Nusret F₁) and squash (Cucurbita pepo cv. Aygır F₁) as rootstocks to improve drought-related performance in cucumber scions (Akıncı F₁ and Baymali F₁). Grafted and non-grafted plants were grown under two irrigation regimes for 21 days: well-watered control (100% field capacity) and a water-withholding drought treatment. Drought stress significantly reduced morphological parameters across most experimental groups. Under drought conditions, the Akıncı F₁/Aygır F₁ combination showed the highest proline accumulation. This biochemical response was accompanied by pronounced reductions in dry leaf and dry biomass. This pattern suggests that proline accumulation is more closely associated with stress severity than with growth maintenance under drought conditions. Conversely, the Baymali F₁/Aygır F₁ combination maintained relatively higher leaf dry weight under drought, suggesting better growth maintenance under drought. Plants grafted onto Nusret F1 generally produced the lowest biomass but showed enhanced proline synthesis, indicating a stronger stress response despite reduced growth. In conclusion, while Aygır F₁ supports higher growth and biomass maintenance under well-watered conditions, drought responses are strongly influenced by scion-rootstock compatibility and distinct physiological strategies, highlighting the importance of distinguishing growth performance from biochemical stress indicators such as proline accumulation. Full article

Regionally, compound agroecological stress arising from both natural and anthropogenic emergy inputs may influence maize transcriptomic responses; however, evidence across multiple scales remains limited. We developed a reproducible five-step framework integrating a macro-level compound stress index, molecular response modules, cross-scale coupling, spatial continuity, and independent field validation. Nine variables (emergy indicators ELR, Fn, and NEYR; climate; soil; and terrain) were PCA-weighted into a Composite Abiotic Stress Intensity Index (CASI; first three PCs = 83.7%; and prefecture-level Moran’s I = 0.463). Across 15 public RNA-seq datasets (286 samples), WGCNA identified five separable modules (drought–heat, reproductive stage heat, low nitrogen/phosphorus, osmotic salt, and chronic compound), 270 core genes, and four cross-module hubs (ZmDREB2A, ZmHSFA2, ZmWRKY33, and ZmNRT2.1). With n = 21, the sCCA (r₁ = 0.81, permutation p = 0.003; LOO-CV r = 0.71), random forest, and spatial error model all confirmed coupling between ELR and the drought–heat module (β = 0.51, p = 0.008). PLS-DA four-zone partitioning (Q² = 0.548) and a county-level second-order trend surface (R² = 0.67) verified spatial continuity. GSVA on five independent field RNA-seq datasets yielded 74.4 to 82.8% core gene directional consistency and Cliff’s δ of 0.59 to 0.68 (large effect), avoiding circular reasoning. The framework enables molecular analysis for precision agriculture and climate-resilient breeding. Full article