Combined Effect of Nitrogen and Phosphorus Fertilizer on the Activity of the Nitrate Reductase Enzyme in Different Wheat Cultivars

Abstract

Some characteristics of nitrogen metabolism were observed in the flag leaf on the main branch of wheat (Triticum aestivum L. and Triticum durum L.) In the current study, nine varieties were chosen and planted as test crop using split plot design and replicate at three times, with nutrient dose as the main plot and varieties as the sub plot treatment cultivated at three different soil nitrogen and phosphorus levels (0, 60, and 120 kg/hac) and (0, 30, and 60 kg/hac). These nitrogen and phosphorus levels were handled using four different treatments, where T1 served as the control, T2 as the nitrogen and phosphorus dose at its optimal level, and T3 as the half-nitrogen and full-phosphate fertilizer doses. Fertilizer dosages of T4 that were half nitrogen and half phosphorus were studied. Flag leaf blades were seen to be engaged in NO-3 assimilation. The flag leaf blade had the highest nitrate reductase activity, free amino acid content, and soluble protein content among all the leaf blades. The activity of nitrate reductase was markedly increased by the addition of nitrogen to the soil. The presence of substrate-dependent enzyme activity was demonstrated inflag leaf tissue. A coincidental association between enzyme activity and the buildup of reduced nitrogen in the plant shown the rise in nitrate reductase activity in response to more nitrogen and the increase vegetative reduced nitrogen. A substantial positive connection was discovered between nitrate reductase activity (expressed as molesN/hac.each season) and grain nitrogen (kg N/hac) at maturity because the transfer of vegetative nitrogen to the grain was homogeneous across treatments. Additionally, there was a strong and positive correlation between seasonal nitrate reductase and grain yields (kg/hac.). In cultivars resistant to lodging, maintaining nitrate reductase activity during the reproductive period might boost grain protein production and avoid the decrease of grain protein percentage that is usually seen when grain yields are high.