Effect of Plant Density and Nitrogen Fertilizer Dosage on Agronomic Characters and Yield of Spring Maize

In order to clarify the optimal application level of nitrogen and plant density in the growth process of spring maize in Heilongjiang province.The effects on the yield of maize and agronomic traits with different plant density and nitrogen fertilizer application were analyzed by a split-plot experiment.The results showed that the Max LAI and yield significantly increase with the increase of density,Increasing nitrogen fertilizer rate for maize could increase effective the Max LAI and yield,the highest yield was achieved at planting density of 90 000plant.hm-2 and nitrogen fertilizer 225kg.hm-2.