Effect of split nitrogen application on grain nitrogen, grain protein and nitrogen harvest of wheat (T. aestivum L.) genotypes

Abstract

A field experiment was conducted with different nitrogen regimes to assess amount of grain nitrogen (N), and N harvest index of wheat genotypes with high nitrate reductase activity (HNR) and low nitrate reductase activity (LNR). Both the N amount in grain and whole plant on unit area basis was higher in ‘HNR’ genotypes than in LNR’ genotypes. The ‘HNR’ genotypes had 21.8% more grain N amount, 7.5% more whole plant N and 14.5% more harvest N index than the ‘LNR’ genotypes. These genotypes also yielded 21.4% more grain protein amount than ‘LNR’ genotypes. An extra amount of nitrogen applied at the time of anthesis increased grain protein yield by 10.8% in ‘HNR’ genotypes, and 12.7% in ‘LNR’ genotypes. On an average, however, the grain protein yield in ‘HNR’ genotypes under this treatment, was 28.4% higher than in ‘LNR’ genotypes.