不同氮肥分配对夏玉米个体生产能力的影响

In view of the existing problems which in conventional practice of applying fertilizer during the summer maize growth stage in Hebei province, we taked Xianyu335 (XY335) and Weike702 (WK702) as the experimental material and eight treatments (N1-N8) were designed in a field experiment to explore effects of nitrogen that was applied by the way of nitrogen fertilizer application by stages in different proportion on the net photosynthetic (Pn), the dry matter accumulation, the grain-filling and the yield of summer maize. The results indicated that N5 showed the highest content of Pn and chlorophyll; the dry matter accumulations of N2, N3, N4, N5 were higher than N1 and N5 took the highest place; both yield and dry matter accumulation of WK702 were greater than XY335. These implied that topdressing would increase the dry matter accumulation, the grain-filling and yield of summer maize obviously when seed fertilizer service was enough.