PHYSIOLOGICAL RESPONSE OF DIFFERENT ACCESSIONS OF SESBANIA SESBAN AND CYAMOPSIS TETRAGONOLOBA UNDER WATER DEFICIT CONDITIONS

Identification of leguminous crops and screening of accessions for drought tolerance are effective approaches to ensure food security and hence to increase soil fertility. To appraise the physiological response of Sesbania sesban L. Merril. and Cyamopsis tetragonoloba L. Taub., their different accessions were evaluated under different field capacities. The accessions were grown in pots, and irrigation was managed to attain 100%, 80%, and 60% field capacity. The photosynthetic attributes and biochemical markers such as photosynthetic pigments, proline, soluble sugars, total soluble proteins, amino acids, glycine betaine, and nutrient contents were employed for evaluation of drought tolerance of all accessions of both crops. All these attributes were adversely affected due to soil moisture deficit conditions, and the response of different accessions to water deficit varied significantly. The soil moisture deficiency significantly reduced the gas exchange attributes, chlorophyll contents, soluble proteins, free amino acids, and N and P contents, while it significantly increased carotenoids, proline, glycine betaine, and K contents. Accession BR99 of Cyamopsis tetragonoloba and accessions Sahianwala and Shahpur of Sesbania sesban showed better performance under soil moisture deficit conditions as compared to the other accessions, so these accessions could be cultivated under semiarid and arid conditions.