EFFECTS OF SALINITY STRESS ON ANTIOXIDANT ENZYME ACTIVITY LEVELS IN RICE CULTIVARS

摘要

Salinity is one of the most important abiotic stresses especially for rice, which is grown under irrigated conditions. To elucidate the effects of salinity stress in rice, three different salinity tolerant varieties laya, Dandi, CSR-27 and one sensitive variety GR-3, were selected. Fifteen days old Seedlings were exposed to 0,100,150,200 mM of Nacl for.24, 48 and 72 hrs. In these four cultivars enzyme activity of superoxidedismutase, catalase and perixidase were studied. Enzyme activity increased with salinity stress. Tolerant varieties showed high antioxidant levels than sensitive cultivar. From this investigation it can be concluded that antioxidants scavenging the reactive oxygen species induced by salt stress. SOD is a major scavenger of O_2 andits enzymatic action results in the formation of H_2O_2 and O_2. Stressed plants can withstand due to the production of these antioxidants.