Abstract: The present paper deals with the productivity and utilization efficiency of fertilizer - N in maize sown in different season in Mengzi, Yunnan province. The results are as follow: There are different utilization of fertilizer - N including the absorbing amount,transferring rate and productivity in the plants sown in different season. They have a depressive trend of utilization efficiency from that sown in Winter(64.7%), in Spring (61.2%), in Summer(49.6%),in Autumn(41.4%).

Key words: Different sowing - season maize

摘要： 本文在云南省蒙自县对不同季节播种玉米的氮肥利用率和生产力进行了研究,结果表明:不同季节播种玉米氮肥的利用率、吸收量、转移率和生产力存在差异.氮肥的利用率由冬玉米(64.7%)、春玉米(61.2%)、夏玉米(49.6%)到秋玉米(41.4%)有降低的趋势,并且与氮肥吸收量存在显著的正相关(r=0.9997).花丝期营养器官的含氮量与氮在籽粒中的分配和收获指数紧密相关(分别为r=0.9714和r=0.9848),表明籽粒中累积的氮来源于花丝期前茎和叶中累积的氮.根据试验结果,提出各季播种玉米的施氮技术.

关键词: 不同播期玉米, 氮转移率, 氮利用率, 氮生产力