Journal of Agronomy and Field Innovations

Background: Black gram (Vigna mungo (L.) Hepper) is an important crop legume grown in South and Southeast Asia for its high protein content and contribution towards sustainable agricultural practices. Drought stress is one of the significant abiotic factors affecting crop growth through adverse effects on water relations and excessive production of reactive oxygen species (ROS) causing oxidative damage to cellular membranes and biomolecules.
Objective: The objective of the present study was to investigate the growth, physiological and biochemical reactions in Vigna mungo seedlings subjected to progressive drought stress with special reference to the activities of antioxidant enzymes and accumulation of osmolytes.
Methods: The seedlings were raised in controlled environment in the greenhouse and subjected to treatments involving control, moderate drought and severe drought stress by withholding irrigation from the plants so that they were at 100% field capacity, 60% field capacity and 30% field capacity, respectively for three weeks. Growth parameters were assessed and also relative water content, chlorophyll content, antioxidant enzymes (SOD, CAT, POD, APX, GR), oxidative stress indicators (MDA, H2O2), and osmolytes (proline, glycine betaine, soluble sugars, soluble proteins) were determined by one-way ANOVA followed by Tukey's HSD post hoc test.
Results: Drought stress caused a considerable drop in parameters like plant height, biomass, relative water content, and chlorophyll content, while root length under normal conditions was long. Activity of antioxidant enzymes and osmolytes levels were growing continuously by the magnitude of stress, along with MDA and H2O2 accumulation which indicate the coordinated enzymatic and osmotic reaction for oxidative and water stress.
Conclusion: The coordinated induction of the antioxidant enzymes and accumulation of osmolytes is a critical adaptation mechanism that allows Vigna mungo plants to be resistant to oxidative stress and provides important physiological indices for developing drought-resistant black gram varieties.