Mechanism of anoxic tolerance in backcross lines developed through Jyothi x Swarna-Sub 1 under submergence stress.

Rice varieties adapted to flash flood exhibit submergence tolerance by maintaining reduced shoot elongation under submerged conditions. This study focuses on the two main physiological traits leading to flash flood tolerance- high survival percentage with reduced shoot elongation under submergence and increased rate of alcoholic fermentation. Sub1introgressed BC3F2 lines exhibited higher survival percentage with moderate shoot elongation under submergence stress for fourteen days similar to the donor parent Swarna- Sub1. Enzymatic activities of alcohol dehydrogenase and pyruvate decarboxylase were monitored for fourteen days under submergence stress. The developed Sub1 introgressed lines and the donor parent Swarna-Sub1 showed higher rates of alcohol dehydrogenase and pyruvate decarboxylase activities under submergence stress thereby maintaining optimum rates of alcoholic fermentation. The findings of this study confirmed the expression of tolerance mechanism in the Sub1introgressedJyothi Backcross Inbred lines under submergence stress.