Nitrogen and phosphorus effects on the growth, phenology, heat and nutrients accumulation and yield of winter maize (Zea mays) in western Indo-Gangetic Plains

Abstract

The results show that plant height, dry weight, crop growth rate (CGR) and leaf area index (LAI) of winter maize were increased with the increase in N levels, the highest values observed at the highest dose of 240 kg/ha. Nitrogen stress delayed tasseling and silking, but hastened maturity of maize. Nitrogen application at each dose tested caused a significant increase in grain yield over control, the highest increase was at 240 kg/ha. The effect of P on grain yield was also significant, and the highest yield was obtained at 26.4 kg/ha after which further increase in P level declined the yield. Thus, N and P individually and interactively influenced growth variables, appearance of phenological stages, heat and nutrient accumulation and yield in winter maize. The interaction between N and P for LAI, nutrient content and dry matter and heat accumulation was observed across physiological stages with higher values of most of these parameters observed at N 240 kg/ha and P 26.4 kg/ha. It is, therefore, concluded that, a combination of N 240 or 160 (being comparable with 240 kg/ha) kg/ha and P 26.4 kg/ha may be recommended for a significant improvement in winter maize growth, yield and nutrient and heat accumulation over a longer growing period under the western IGP conditions.