Effect of different doses of nitrogen on growth, yield and yield attributes of spring maize in Madichaur, Rolpa, Nepal

The significantly highest plant height (198.06 cm) was measured for treatment 120 kg N/ha and the lowest plant height (162.6 cm) was measured for treatment 0 kg N/ha at 95 days after sowing. Likewise, significantly shortest period to tasseling (74.3 days) and silking (78.0 days) under the application of 120 kg N/ha but at par with treatment 90 kg N/ha (75.1 days) and (78.7days) respectively and longest period to tasseling (79.7 days) and silking (85.4 days) under the application of 0kg N/ha but at par with treatment 30 kg N/ha (78.7) and (84.6 days) respectively was obtained. Similarly, the highest grain yield (3.7 t/ha) was obtained for treatment 120 kg N /ha which was significantly higher than all other treatments but at par with treatment 90 kg N/ha (3.5 t/ha) and the lowest grain yield (1.5 t/ha) was obtained for treatment 0 kg N/ha which was significantly lower than all other treatments but at par with treatment 30 kg N/ha (1.8t/ha). Overall study shows that almost all parameters of spring maize increase significantly with the increasing dose of nitrogen up to 90kg/ha. But no significant difference was observed on yield and yield attributes while increasing the nitrogen dose from 90 to 120 kg/ha. Thus, for the optimum and sustainable production of spring maize, 90 kg N/ha can be used as a recommended dose in Madichaur, Rolpa.