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作 者 ：赵士诚, 裴雪霞, 何萍, 张秀芝, 李科江

期 刊 ：植物营养与肥料学报 2010年 16卷 2期 页码：492-497

关键词：氮肥后移；夏玉米；氮肥利用率；硝态氮；

Keywords:postponing N application, summer maize, N use efficiency, NO-3-N,

摘 要 ：采用田间试验研究了氮肥减量后移对土壤氮素供应和夏玉米氮素吸收利用的影响。结果表明，与农民习惯施肥（N 240 kg/hm²，基肥和大喇叭口追肥为1∶2）相比，氮肥减量后移（N 168 kg/hm²，基肥、大喇叭口肥和吐丝肥为1∶3∶1）处理的产量、植株干物质积累量、植株氮积累量和积累速率均没有降低，而氮肥利用率显著增加。氮肥减量后移可使耕层无机氮供应较好地与作物吸收同步，降低收获期0—100 cm土层硝态氮积累，减少氮素的田间表观损失。基于夏玉米不同生育阶段的氮素吸收特征进行氮肥减量后移可节省氮肥30%，是较为理想的氮素施用方式。

Abstract:Field experiment was conducted to investigate effects of reducing and postponing N application on soil N supply, plant N uptake and utilization of summer maize. The results show that N accumulation rate is increased under the reducing and postponing N application (N 168 kg/ha, 1/5 basal, 3/5 topdressing at stalk enlongation stage and 1/5 topdressing at silking stage, respectively) compared with farmers‘ practice (N 240 kg/ha, 1/3 basal and 2/3 topdressing at booting stage, respectively), while N use efficiency, dry biomass accumulation, yield and N accumulation amount are not decreased. Moreover, the reducing and postponing N application can improve synchronization of soil N supply and crop demand during the maize growth stages, decrease NO^-₃-N accumulation of 0-100 cm soil profile, and reduce field apparent N loss at maturity. Therefore, the reducing and postponing N application based on summer maize N uptake at different growth stages is a feasible N management practice, and nitrogen fertilizer could be saved by 30% as compared with farmers‘ practice.

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