Mitigation of Drought Stress by 24-Epibarassinolide and 28-Homobrassinolide in Pigeon Pea Seedlings

Abstract

This article encompasses the results on the effects of 24-epibrassinolide (EBL) and 28-homobrassinolide (HBL) on germination, seedling growth and antioxidative defense of pigeon pea (Cajanuscajan(L.) Millsp.)under Polyethylene glycol 6000 (PEG) induced drought stress. Drought stress significantly decreased seed germination, growth and dry mass of pigeon pea. However, both EBL and HBL treatments alleviated the negative effects of drought on germination, growth and increased the dry mass accumulation. Drought stress induced hydrogen peroxide production, lipid peroxidation and electrolyte leakage was significantly counteracted by both EBL and HBL treatments. Supplementation of EBL and HBL enhanced the activities of antioxidative enzymes viz., catalase, peroxidase, superoxide dismutase glutathione reductase and ascorbate peroxidase in both unstressed and drought stressed seedlings. Further, BRs increased the proline, Glycine betaine and ascorbic acid levels in stressed seedlings. The present study demonstrated the ameliorating ability of EBL and HBL on the drought stress induced inhibition of germination and seedling growth of C. cajanby improving the antioxidative defense system.