摘要： 以提高夏玉米氮肥利用率、减少氮肥污染为着眼点,研究了不同施氮时期(三叶期施氮、大喇叭口期施氮、三叶期施氮结合大喇叭口期展追氮)对夏玉米植株碳氮运转及氮肥利用率的影响.结果表明,与不施氮相比,施氮降低了茎鞘、叶片等营养器官花前贮藏物质运转量和运转率以及总运转量和运转率,减弱了玉米各营养器官花前贮藏物质向籽粒的再运转能力.施氮降低了植株花前贮藏氮素总运转量和运转率,提高了籽粒全氮含量.三叶期施氮结合大喇叭口期追氮处理下夏玉米的氮肥利用率最高,较三叶期施氮和大喇叭口期施氮分别提高了21.8个百分点和22.8个百分点,较好的提高了夏玉米当季氮肥利用率,能够有效地降低因氮素损失而造成的农田污染.

关键词: 夏玉米, 施氮时期, 物质运转, 氮肥利用率

Abstract: Aimed to reduce pollution of nitrogen fertilizer(NF)and heighten nitrogen use efficiency(NUE)in summer maize,effects of nitrogen application time(applied nitrogen in 32leaf stage,applied nitrogen in 122leaf stage,applied nitro2 gen in 32leaf stage and 122leaf stage)on carbon assimilate and nitrogen translocation and NUE were studied in 2007. The main results as follows,nitrogen application reduced the amounts and remobilization rate of per2anthesis stored assimilates and total amount of pre2anthesis stored assimilate,weakened the ability of per2anthesis stored assimilates re2transportation to grain.Nitrogen application reduced the amounts and remobilization rate of per2anthesis stored nitrogen,increased the content of nitrogen in grain. In treatments of three nitrogen application time,the NUE of treatment of applied nitrogen in 32leaf stage and 122leaf stage was top,and increased 2118 percent pionts and 2218 persent points than the others,it im2 proved the NUE of summer maize in the stage,and reduced the farm pollution by losing of nitrogen.

Key words: Summer maize, N application time, Assimilate transportation, NUE

中图分类号: 

• S513

• S143