Effects of Nitrogen Fertilizer Rates on Yield and Yield Components of Maize (Zea mays L.)

Maize is one of the most important cereal crops in the world. To investigate the effects of nitrogen fertilizer rates on growth and yield of maize and to determine the suitable nitrogen fertilizer rate, an experiment was conducted by using Randomized complete block design (RCBD) with four replications at Shwe Baho village, Zayarthiri Township, Nay Pyi Taw in post monsoon season and monsoon season. The treatments were T1 (no nitrogen application), T2 (90 kg N ha-1), T3 (120 kg N ha-1), T4 (150 kg N ha-1) and T5 (180 kg N ha-1) treatments. The tested maize variety was pacific-789 hybrid. According to the results, application of nitrogen gave the significant effect on grain yield and yield components of maize in both seasons. The superior maize yield was observed in all nitrogen treatments compared to control. The use of the highest nitrogen fertilizer rate (180 kg N ha-¹) in T5 gave the significant highest grain yield (7696.6 kg ha-¹) in post monsoon season and (8764.5 kg ha-¹) in monsoon season, respectively. In both seasons, the grain yield in T5 treatment was significantly increased about 62% over T1 treatment. Therefore, the application of nitrogen with the rate of T5 (180 kg ha-1) might be the appropriate rate to maximize the maize production. Considering the increased grain yield of the hybrid maize, nitrogen rate of T5 (180 kg ha-1) could be achieved in this study area.