Biochemistry Laboratory Department of Botany, Utkal University, Bhubaneswar
The rate of nitrate uptake, nitrate content and nitrate reductase induction of 5 cultivars of rice seedlings were studied. The nitrate uptake was initially low but increased subsequently following 2 hours of induction. The rate of nitrate influx during the period of induction was correlated with the pattern of nitrate reductase activity in shoots but not in roots. The total nitrate content in both root and shoot tissue were not markedly different compared to nitrate, reductase activity. Some adaptive cultivars like DR-LK-41, Jaya and SR-26B had higher nitrate content and enzyme activities compared to others. Studies with inhibitors indicated that nitrate reductase synthesis was aided by nitrate uptake.
