Evaluation of blackgram genotypes for drought tolerance based on root dynamics and gas exchange parameters

Ninety four genotypes of black gram were evaluated under rainfed condition for their biometric characters viz., plant height, number of pods plant-1, number of seeds pod-1, 100 seed weight and seed yield plant-1 for preliminary screening to identify the best performing genotype. Based on their yield performance, eight genotypes viz., RU8-705, PALAVAYALLOCAL, T9, PHM 8, ADT 3, CBG-09-06, VANNIYUR-LOCAL and CBG-09-13 were selected and raised in three environments. Among them, two genotypes viz., T 9 and CBG-09-13 were selected and their root parameters viz., root and shoot length, shoot length, number of roots, root diameter, fresh weight of root, fresh weight of shoot, dry weight of root, dry weight of shoot, root volume and gas exchange characters viz., net photosynthetic rate, leaf temperature, stomatal conductance and intercellular CO2 were studied to identify the best genotype among them suitable for moisture stress condition. Based on the results, it was found that CBG-09-13 performed well under moisture stress condition.