Physiological & Biochemical changes in Rice crop in Submergence Stress

Field experiment was conducted in Adaptive Research Station, Sakhigopal, Puri during kharif 2012 to screen out the rice varieties for their relative tolerance to submerged condition basing upon the morpho-physio-biochemical characters. The varieties such as Sarala, Hanseswari, Varshadhan, Bankoi, and Champa & CR-925-2 were taken in transplanting condition in lowland where the water depth ranged from 50 cm to 100 cm during its vegetative to reproductive stage. The highest yield was recorded in Varshadhan as compared to susceptible variety Bankoi under submerged condition due to higher value of number of grains/panicle, number of matured grains /panicle, more number of effective tillers per plant .The defense mechanism contributed by the enzymes like peroxidase, catalase & SOD was found to be 18.20%, 18.75% &14.88% respectively increase in Varshadhan as compared to Bankoi under anoxia developed due to post submerged condition. Similarly the carbohydrate, sugar & sucrose content of Varshadhan exhibited highest value both before & after the submergence among the varieties. It was concluded that the survival percentage of Varshadhan was highest as compared to the other varieties.