ABSTRACT Biofuels can play an important role to reduce fossil fuels consumption and decrease carbon dioxide emissions. However, current biofuels derived from food crops can exacerbate food security concerns due to their competition for cropland and resources. Second‐generation biofuels obtained from non‐food crops can represent a promising opportunity to overcome this conflict. Safflower ( Carthamus tinctorius L .), an under‐utilised crop (UUC), shows promise for biofuel production due to its oil properties and resilience in extreme/unsuitable environments. In this study, we evaluated the response of two safflower genotypes CWL990L (CWL) and Oscar (OS) under two different water treatments: well‐watered (100% of ETc) and half‐watered (HW) (50% of ETc) across three locations in Southern Italy. CWL maintained high shoot biomass, seed yield and oil yield under HW conditions in the two deepest soils, whereas OS showed reductions up to 75% and 62% in biomass and seed yield, respectively. CWL had a reduced relative water content by only 6% (vs. 20% in OS), increased leaf mass per area by 26%, and developed a root system with 70% steeper root angle. In contrast, OS showed a much more limited plasticity in these traits. However, we observed significant variations in productivity across locations due to the different pedoclimates. In conclusion, safflower holds great potential as a sustainable biofuel feedstock. These results also demonstrate that resilient genotypes that require moderate agronomic inputs can maintain good yields while adapting to diverse environmental conditions.

ABSTRACT Cowpea ( Vigna unguiculata L. Walp.) is a climate‐resilient legume essential for food security and dryland farming in semi‐arid regions of India. This study delineates climate‐smart suitability zones by integrating Ensemble Species Distribution Modelling (ESDM) with Analytic Hierarchy Process–Multi‐Criteria Evaluation (AHP–MCE) to incorporate climatic, soil, and land‐use determinants. Seven modelling algorithms (GLM, GAM, MARS, CTA, RF, ANN, SVM) were applied under baseline, 2050, and 2070 climates (RCP 4.5 and 8.5), achieving strong ensemble performance (AUC = 0.84–0.88; TSS = 0.62–0.67). Precipitation variables dominated current suitability, while temperature extremes shaped future patterns. Integrating soil and LULC data through AHP–MCE substantially improved spatial precision, expanding optimum suitability zones and identifying new target regions in central, southern and eastern India. The integrated framework offers practical value for breeding programs (identifying heat‐ and drought‐prone target environments), agricultural policy and investment (site‐specific irrigation, diversification, climate‐risk planning), and farm‐level decision making. By quantitatively combining climatic, soil and land‐use predictors in a unified GIS‐based ensemble system, an advancement over existing legume suitability studies, this work provides a scalable tool for climate‐resilient crop planning and adaptive agricultural development.

ABSTRACT The impact of climate change, as evidenced by increasingly higher temperatures and decreasing precipitation, presents a substantial threat to wheat crops globally. In the Indo‐Gangetic Plains (IGP), which is the breadbasket of India, it is evolving as the biggest threat to food security and livelihoods for the farming fraternity. A 3‐year field study evaluated the effects of drought and heat stress on wheat yield and how these effects interact with morphophysiological traits. This study deployed staggered sowing and controlled irrigation to simulate droughts synchronising with vegetative and reproductive stages of the crop across 13 wheat cultivars selected based on their prevalence among farmers. Principal component analysis (PCA) and Pearson's correlation matrices were used to reduce data dimensionality for shortlisting independent morphophysiological variables before measuring average treatment effects. Findings highlighted a decline in levels of relative water content (RWC), chlorophyll and carotenoid under stress treatments. A sharp reduction of almost 50% in grain yield was observed when the crop encountered drought and heat stress simultaneously. Another finding revealed that RWC, chlorophyll content and proline accumulation were strongly associated with resilience to these stresses. The study identified two wheat cultivars (HD 2967 and HI 1531) that demonstrated superiority in coping with stress conditions consistently under both timely and late sowing conditions. These findings are insightful for wheat breeders, highlighting potential plant traits for climate‐resilient breeding programmes. The study also generated important evidence that can potentially inform policy makers around sowing time, irrigation scheduling and seed systems of wheat in eastern India and similar agroecological regions.

ABSTRACT The cultivation strategy of ‘postponed nitrogen with increased panicle fertilization (PNIPF)’ boosts rice yield but the balance between lodging remains unclear. We evaluated three panicle nitrogen ratios (0%, 20% and 40% of total 165 kg N ha −1 ) in two late indica rice varieties ( Meixiangzhan 2 and Taiyou 871 ) to assess this trade‐off. Results demonstrated that: (1) Compared to R 0 , PNIPF to 20% showed no difference on yield, while R 4 raised grain yield by 4.84% and 8.69% but increased lodging index by 30.5% and 35.8% in TY871 and MXZ2. (2) Relative to R 0 , R 4 induced taller plants with elevated center of gravity, reduced culm diameter, diminished culm mechanical strength, and decreased structural carbohydrate content (cellulose −29.2%, lignin −23.8%). The effect of R 2 is weaker than R 4 on plant morphology. (3) Compared to R 0 , R 4 manifested more profound anatomical deterioration than R 2 . (4) Significant variety differences existed; PNIPF exhibited a more profound impact on MXZ2 than TY871 by inferior morphological, physiological and anatomical traits. We recommend limiting panicle nitrogen to below 20% to achieve synergistic improvement of yield and lodging resistance in high‐quality late indica rice production.

ABSTRACT Drought stress prior to anthesis slows down maize silk extension and thus causes the greater anthesis and silking interval, resulting in a significant reduction in grain set. This study aims to characterise the transcriptional and physiological responses of silk elongation to moderate drought stress. A trial of two hybrids with contrasting drought tolerance, AN591 and ZD909, under well‐watered (WW) and moderate flowering drought stress (FDS) conditions was performed. Compared to the WW group, the silking under FDS was delayed by 1 day in AN591 and by 3.3 days in ZD909, suggesting that AN591 exhibits greater resilience to FDS than ZD909. The comparative transcriptomic profiling between FDS and WW for both hybrids highlighted the significance of sugar metabolism in promoting silk elongation, while also identifying phenylalanine metabolism and phytohormone signalling as inhibitory factors. Pathways exclusive to AN591 were largely linked to carbon and energy metabolism, while those in ZD909 were primarily associated with stress defence, suggesting AN591 was better adapted to FDS. Physiological assays confirmed that stronger sucrose decomposition in AN591, regulated by cell wall invertase, alleviated FDS‐induced suppression on silk elongation. This may also explain its reduced lignin synthesis and other defence responses. Conversely, the unique phytohormone signalling in ZD909, characterised by negative auxin response and positive abscisic acid response, may further exacerbate the inhibitory effect on silk elongation by driving more sugar consumption. Together, combined transcriptomic and physiological analyses revealed that the trade‐off between growth and defence was mediated through adjustments in sucrose metabolism, phytohormone signalling and secondary metabolic pathways.

ABSTRACT The cultivation of soybean ( Glycine max (L.) Merr.) is becoming more widespread for its desirable high protein content and versatile use as a feed crop and key ingredient for transformed food products. However, high temperatures attributed to climate change continue to present challenges for crop productivity and yield, thus impacting global food security. Seed set in soybean requires fertilisation, and the performance of the male gametophyte (pollen) is thus a fundamental element determining yield. Pollen is highly susceptible to heat stress and in particular the progamic phase—the growth of the pollen tube through the female flower tissues—is highly sensitive even to short and moderate temperature shocks. To determine the impact of high temperature stress on soybean reproduction in early maturing varieties, pollen from three different soybean lines in MG00 was exposed to high temperature treatments. Mean cardinal temperatures ( T min , T opt , T max ) were established to be 10.3°C, 30.2°C, and 50.1°C, respectively, for coupled pollen tube length and 12.0°C, 33.7°C and 55.4°C, respectively, for uncoupled pollen tube length. T opt and T max for pollen germination were at 21.6°C and 54.6°C, respectively. This suggests that high temperature stress affects all stages of the progamic phase in early maturing soybean varieties with pollen germination being more susceptible than pollen tube growth. A decrease in both pollen germination rate and pollen tube length was observed in vitro at temperatures above optimum ( T opt ). Pointing at cellular processes particularly affected by temperature stress were observations of aberrant callose accumulation at the growing tip of heat‐stressed pollen tubes while cellulose distribution was unaltered.

ABSTRACT Climate‐induced increases in temperature and water scarcity threaten global soybean production. While the individual effects of drought or heat stress on yield are well documented, their combined impact on specific yield components remains poorly defined. To address this gap, we conducted a two‐year study in Japan using a temperature gradient chamber and a single soybean cultivar. The study applied four temperature gradients under well‐watered and drought stress conditions to examine seed yield and its components. Combined drought and heat stress reduced total yield more than either stress alone. In 2024, average yield under combined stress declined by 19.4% compared to 2023, coinciding with an increase of 1.5 kPa in maximum vapour pressure deficit and 2.5°C in maximum temperature. This yield reduction was primarily attributed to lower seed weight on branches rather than on the main stem. Pearson correlation and multiple regression analyses identified the number of nodes per branch as the key yield determinant under stress conditions. We further found that the transition from vegetative growth to beginning bloom was the most stress‐sensitive stage. During this period, maximum temperature and vapour pressure deficit reached 53.3°C and 10.7 kPa, significantly inhibiting node formation on branches and limiting subsequent pod and seed set. These findings advance understanding of how concurrent drought and heat stress constrain soybean yield through specific developmental pathways, and underscore the need to incorporate branch‐level traits into stress‐resilient breeding strategies.

ABSTRACT Water stress considerably impairs rice growth and reduces grain yield. Brassinolide (BR) can mitigate the detrimental impacts of various stresses on rice growth. However, the effects of BR on rice root growth under water stress have yet to be studied. This research investigated the impacts of BR application on root morphological and physiological traits, nitrogen accumulation and utilisation, photosynthesis and grain yield in rice subjected to water deficiency. A pool experiment was conducted with two irrigation regimes, namely, continuous watering (W) and water deficit (D) conditions, and four BR concentrations, namely, 0 (B0), 0.1 (B1), 1 (B2) and 5 (B3) μmol L −1 , over 2 years. Under the W regime, the application of BR increased the grain yield by 9.6%–54.2% compared with that under WB0. At the same BR level, the grain yield under the D treatment was significantly lower than that under the W treatment. However, compared with DB0, BR application at 0.1 μmol L −1 significantly increased the length, surface area, volume, diameter, activity and total and active absorbing area of the roots; increased the activities of nitrate reductase and glutamine synthetase in the roots; and promoted nitrogen accumulation and utilisation and photosynthesis. Compared with DB0, DB1 resulted in a significantly greater rice yield, with an increase of 67.2%–68.4%. Moreover, the grain yield of DB1 was significantly greater than that of WB0. The grain yield of DB2, which was significantly greater than that of DB0, was similar to that of WB0. DB3 did not result in any yield improvement over DB0. These results suggest that the application of BR at a low concentration promotes the morphological and physiological traits of rice roots under water‐deficient conditions, thereby increasing nitrogen uptake, use efficiency and grain yield.

ABSTRACTClimate‐driven heat stress increasingly threatens waxy maize production, particularly during the jointing stage. Although exogenous salicylic acid (SA) and nitric oxide (NO) are known to improve heat tolerance in plants, their combined (SA‐NO) mechanisms in waxy maize remain unclear. This study investigated the effects of exogenous SA, NO and SA‐NO co‐application on alleviating heat stress in waxy maize during the jointing stage. Results revealed that high temperature (HT) severely impaired plant growth, elevating leaf oxidative damage, disrupting photosynthetic systems and reducing shoot dry weight by 42.7%, compared with the control. Exogenous application of SA, NO and SA‐NO mitigated these adverse effects, with the SA‐NO combination being most effective. Compared with HT, the SA‐NO reduced malondialdehyde and reactive oxygen species levels and increased shoot dry weight by 33.3%. Transcriptomic analysis revealed that SA‐NO upregulated photosynthesis‐related genes, stabilised starch and sucrose metabolism and glycolysis/gluconeogenesis pathways and enhanced activities of antioxidant enzymes. These changes helped reverse the HT‐induced declines in photosynthetic parameters. Additionally, SA‐NO restored hormonal balance by modulating ABA, IAA and CTK pathways, upregulating PYR/PYL and CRE1 while downregulating PP2C and SnRK2. These results demonstrate that SA‐NO synergistically improves thermotolerance through enhanced antioxidant capacity, restored photosynthetic and hormonal regulation. This strategy offers a promising approach to protect heat‐stressed crops in a climate of change.