Studies on some biomarkers for submergence tolerance in rice cultivars

Abstract In the present study, three rice varieties namely Swarna, Swarna Sub1A, and FR13A were evaluated on the basis of their antioxidative responses to screen submergence tolerance capabilities. Fourteen-day- old seedlings were completely submerged for 7 days and were observed to have a significant variation in reactive oxygen species like H2O2 and O2-. The variety Swarna recorded maximum accumulation of H2O2 and O2- and showed more susceptibility to submergence. On the other hand, chlorophyll content did not show highly significant variation among the varieties thus proving its uncertainty to be a trait under submergence. The activity of superoxide dismutase (SOD) had declined throughout the submergence period irrespective of varieties, being maximum in Swarna Sub1A and minimum in Swarna. Almost similar phenomenon was recorded in other two varieties showing their submergence susceptibility however with insignificant variation in terms of APX and CAT. The results from the present experiment point at the fact of submergence tolerance with the view of oxidative sensitivity in rice varieties and finally their possible roles as screening indices for submergence tolerance are discussed.