Integrative multivariate analysis of morphological, physiological, and biochemical responses of upland cotton to water deficit at the reproductive stage

Salicylic Acid Improves Morpho-Physiological Traits and Biomass of Kale under Drought Stress

Drought stress in agricultural land disrupts the physiological processes, growth, and yield of kale (Brassica oleracea L. var. acephala). This study evaluated the physiological responses, growth, and yield of kale treated with salicylic acid, a potential strategy to enhance plant tolerance to drought stress, in a greenhouse at the Department of Agriculture, Universitas Diponegoro, Semarang. A 4 × 4 factorial experiment was arranged in a Completely Randomized Design (CRD) with three replications. The first factor was drought level (100%, 80%, 60%, and 40% field capacity). The second factor was salicylic acid (SA) concentration 0, 0.75, 1.5, and 2.25 mM). The results indicated that physiological responses (chlorophyll a, chlorophyll b, total chlorophyll, relative water content, and electrolyte leakage) remained largely stable under moderate drought stress (60% FC), whereas plant growth parameters (plant height, leaf number, and leaf area) were reduced by 14.5–20.7% compared with the control (100% FC). At 40% FC, both physiological and growth responses were more severely affected; electrolyte leakage increased markedly, and plant height, leaf area, and dry biomass weight decreased by 24.4%, 47.2%, and 60.5%, respectively, compared with the control (P < 0.05). The best treatment was the application of 1.5 mM salicylic acid, which increased the relative water content by 4.13% and decreased the electrolyte leakage by 34.70% compared to untreated plants (P < 0.05). This concentration was likely more effective due to optimal stomatal regulation, increased antioxidant enzyme activity, and maintained membrane integrity, indicating that 1.5 mM SA has potential as a biostimulant to improve kale water status and membrane stability. However, field validation across locations and seasons is needed before recommending it for dryland farming.

Pre-breeding for drought tolerance in Lotus tenuis under saline-sodic soil conditions

Developing drought-tolerant forage legumes adapted to saline-sodic soils is essential to sustaining livestock production in marginal environments. Pre-breeding programs allow the identification of useful genetic variation within naturalized populations for this purpose. This study aimed to (i) compare the performance of half-sib families (HSFs) from a naturalized population of Lotus tenuis, with a commercial cultivar under drought stress, and (ii) identify key traits and promising materials for breeding. Twenty HSFs and one cultivar were evaluated under controlled conditions in a factorial design with two water regimes (field capacity and drought). Morphological, physiological and biochemical traits were measured, including aerial dry biomass, number of branches, leaf temperature, ion concentrations (Na+, K+), relative water content and oxidative stress indicators. Narrow-sense heritability and genetic correlations were estimated, and multivariate analyses were performed. Drought significantly reduced growth and altered physiological traits, with differential responses among genotypes. Some HSFs matched or exceeded the cultivar for aerial biomass production under stress. High heritability (h2 > 0.8) was observed for aerial biomass, number of branches, leaf temperature and ion concentrations under drought. Growth traits were positively correlated and negatively associated with leaf temperature and Na+. Five HSFs (9, 12, 13, 16, and 20) were identified as promising materials on the basis of their performance for aerial biomass, leaf temperature, and Na+ concentration, traits identified as reliable selection criteria for drought tolerance under saline-sodic soil conditions in L. tenuis. These families provide valuable resources for breeding drought-tolerant cultivars for saline drylands, although further selection and recombination are required.

Differential response of wild and domesticated Solanum genotypes to water stress

Identification of adaptive traits and mechanisms in tropical soybean lines under drought stress from flowering to pod formation1

ABSTRACT Drought stress reduces soybean [Glycine max (L.)] yield stability in tropical environments, particularly from flowering to pod formation. This study aimed to identify adaptive traits and underlying mechanisms of tropical soybean lines under water-limited conditions, as well as to assess the selection potential under non-stress environments. Twenty-five high-yield soybean genotypes carrying the long juvenile (lj) and pod dehiscence1 (pdh1) genes were selected and evaluated under normal (± 80 % of the field capacity - FC) and water-deficit (± 50 % FC) conditions. Two potentially tolerant (which demonstrated a higher capacity to maintain physiological performance and metabolic stability under water deficit) and two susceptible genotypes were identified for further in-depth evaluation. Proline and malondialdehyde (MDA) were negatively and significantly correlated with grain yield under normal and water-deficit conditions. Both characters showed high broad-sense heritability across the environments, indicating strong genetic control and stable phenotypic expression. The simultaneous increase of proline and MDA is associated with reduced grain yield, indicating a stress-induced metabolic trade-off in which carbon and energy are redirected from reproductive development toward cellular protection mechanisms in the soybean genotypes.

Physiological responses of some ancient walnut genotypes to drought: implications for germplasm utilization

Plant Breeding as a tool to cope with drought using the HvFSDI gene

Drought stress is a major constraint to wheat and barley production, causing oxidative damage, metabolic disturbances, and reduced crop productivity under changing climatic conditions. Understanding the physiological and biochemical mechanisms associated with drought tolerance is essential for identifying resilient cultivars and supporting the development of climate resilient cereal production systems. The physiological, biochemical and agronomic responses of two varieties of barley to two irrigation periods: P1 - irrigation every 15 days and P2 – irrigation every 20 days) were evaluated in the winter season 2024 at the University of Baghdad, using a randomised complete block design with factorial arrangement and three replications. Growth characters, activities of antioxidant enzymes (CAT, SOD and GPX) and yield attributes and grain yield were measured. Variety 1 was superior to variety 2 in agronomic performance. Variety 2 had significantly higher plant height (79.6 cm), leaf area (10.95 cm2), number of spikes (250.08 spikesm2), kernels per spike (48.9) and grain yield (4.63 t/ha) than variety 1. The second irrigation period (P2) improved plant height, number of spikes, number of kernels per spike and grain yield and the activities of SOD and GPX, indicating better antioxidant responses against oxidative stress. However, CAT activity was higher in P1, indicating higher detoxification of hydrogen peroxide in shorter irrigation intervals. In general, the interaction between Variety 2 and P2 yielded the highest values of growth, antioxidant activity and yield. These results indicated that Variety 2 had better physiological and biochemical mechanisms to cope with drought stress and produced more under prolonged irrigation interval.