Study of enzymatic activity in rice (Oryza sativa L.) genotypes under different nitrogen levels

Abstract

The field experiment was laid out in a split plot design with three nitrogen levels of T1 (120 kg N ha-1), T2 (80 kg N ha-1) and T3 (120 kg N ha-1) as main plot treatments and twenty screend rice genotypes as sub plot treatments. To identify nitrogen use efficient cultivars enzymatic activity play an important role in the selection criteria. Nitrate reductase, Nitrite reductase and Glutamine synthetase activities were increased with higher level of nitrogen except Glutamate synthase activity, which showed opposite pattern, Glutamate synthase activity decreases with higher nitrogen levels. Genotypes which were recorded maximum enzymatic activities are DXD (124)-3-28, DXD (124)-17-192, DXD (124)-17-193, DXD (124)-15-164, DXD (124)-17-210, DXD (124)-11-133 and DXD (124)-9-91.