Effects of complete plant submergence on vegetative growth,grain yield and some biochemical changes in rice plants

Summary Complete plant submergence for 6 or 9 days at 20 days after transplanting effected the same decrease in grain yield as submergence for 12 days at 40 days after transplanting. With increasing duration of submergence, tiller number, green leaves and dry weight of all varieties tested decreased. The decrease was less in the flood tolerant variety FR 13A than in other varieties. Contents of reducing sugars and amylase activity also decreased with increasing duration of submergence. The reducing sugar contents and amylase activity were higher and peroxidase activity was lower in flood tolerant variety FR 13A than in other varieties. The N contents increased and P and K contents decreased with duration of submergence.