Effect of brassinosteroid (Brassinolide) on seedling traits, morphology and metabolism in mungbean under salinity stress

The experiment was conducted in stressed and non stressed condition during kharif season 2014 at Department of Plant Physiology, Banaras Hindu University, Varanasi, India. Mungbean seeds were treated with different concentrations of brassinolide (BL) 0.01 mM and 0.05 mM in combination with sodium chloride (NaCl) 100 mM, BL 0.05 mM alone with control. The whole experiment was done in Petriplates and pots in growth chamber and net house, and was laid out in complete randomized design. The results of experiment revealed that plant growth regulator brassinolide (BL 0.05 mM) with salinity stress increased the germination percentage by three folds, root length by two folds, shoot height by two folds, SPAD value by one fold, nitrate reductase activity by seven folds and proline content by one fold when compared with salinity stressed condition (NaCl 100 mM) in both HUM-16 and HUM-12 genotypes at 30 days after sowing (DAS). The increase in above parameters was found at par with BL 0.01 mM concentration. Stressed plants exhibited poor growth and biochemical parameters were significantly reduced. However, the follow up application of BL (0.01 mM and 0.05 mM) neutralized the damaging effects of the salinity on the plants.