Effect of nitrogen and zinc fertilization on quality and productivity of maize (Zea mays L.)

A field experiment was conducted to study four levels of nitrogen and three levels of zinc on quality and yield of maize. The results revealed that application of N up to 100 kg/ha recorded significantly higher leaf area index at all the growth stages and was superior in increasing relative growth rate (RGR) and not assimilation rate (NAR) between 25 and 50 days compared to 60 kg/ha. Application of 100 and 120 kg N/ha was statistically at par and these were found significantly superior in increasing cob/plant and shelling per cent over 60 and 80 kg N/ha. Application of 80 and 100 kg N/ha significantly increased grain and stover yield over 60 kg N/ha. A significant increase in N, P and Zn content and their uptake was also recorded in these treatments. Protein content in grain and chlorophyll in leaves increased significantly with successive increase in nitrogen doses up to 100 N/ha. Application of zinc up to 5.0 kg/ha significantly enhanced leaf area index and shelling per cent compared to 2.5 kg zinc/ha. Application of 5.0 kg Zn/ha significantly increased grain and stover yields of maize over 2.5 kg Zn/ha. A significant increase in N and P content and their uptake was also recorded at 5.0 kg Zn/ha. Application of 5.0 kg Zn/ha also recorded significantly higher chlorophyll (1.81 mg/g 50 DAS) and protein content of grain (10.01%).