Abstract
Eight short statured mutants viz. DM-16-5-1, DM-2, DM-107-4, DM-15-4, DM-15-11, DM-24, DM-38 and DM-179-1 and two standard varieties, Basmati 370 and IR 6 were studied for the activities of amylase and nitrate reductase (NR). Amylase (alpha and beta) was studied at seedling stage whereas nitrate reductase activity was estimated at 4 different growth stages; seedling, tillering, flowering and maturity. There was no significant difference between the mutants and the tall variety with respect to amylase activity. However, a clear cut difference was observed between all the mutants and varieties with respect to alpha and beta amylase activities. Alpha amylase activitywas higher than beta amylase activity in Basmati 370, IR 6, DM-16-5-1, DM-15-4, DM-15-11, DM-24, DM-38 and DM-179-1 whereas beta amylase activity was slightly higher in DM-2 and DM-107-4. Nitrate reductase activity decreased from seedling stage with the progress of growth. Maximum activity of nitrate reducatse was observed in mutants DM-24 and minimum in DM-179-1. Semidwarf mutants DM-24 DM-2, DM-16-5-1 and DM-38 by virtue of their showing consistently high activity at all the stages seem to be promising and could be used in the hybridization programme for inducting nitrate reducatse activity.
