Cross talk among hormones during growth of Mung Bean [Vigna radiata (L.) Wilczek] seedlings under water stress

Plant growth, most sensitive to drought stress, showed differential responses when subjected to simulated water stress. Present study was aimed to elucidate the hormonal basis and their possible cross talk involved in differential responses of plants under water stress induced by PEG-6000 solution by using Vigna radiata seedlings. Plant hormones like ABA, GA and ethylene (ethrel) and their biosynthesis inhibitors- fluridone, paclobutrazole and cobalt chloride, respectively, were used for such study. Both exogenous ABA (10µM) and mild PEG-induced stress (?w -0.5MPa) promoted root growth, which was not due to suppression of ethylene biosynthesis. On the other hand GA, though inhibited root growth, was associated with shoot (hypocotyl) growth but could not overcome stress-induced shoot growth inhibition. Ethylene appeared to have no role in water stress-induced growth responses either in roots or hypocotyls.