为确定固定道垄作栽培方式下小麦适宜的氮肥投入量，分别设置4个施氮水平(0、120、180、240 kg/hm2)，研究了固定道垄作栽培方式下不同施氮量对小麦干物质积累、产量和氮肥利用率等的影响。结果表明，氮肥能够明显促进小麦生长发育，显著提高小麦产量及氮肥利用率。施氮量为180 kg/hm2时，小麦叶面积指数、干物质积累量较高；籽粒产量最高，为5 883.3 kg/hm2；氮肥吸收利用率高达52.10%，氮肥农学利用率为18.77 kg/kg，均显著高于施氮量240 kg/hm2的处理。综合分析认为，河西绿洲灌区固定道垄作栽培方式下小麦的适宜施氮量为180 kg/hm2。

Four nitrogen levels(0， 120， 180， 240 kg/hm2) were set to determine the appropriate n fertilizer input in wheat under fixed ridge cultivation. The effects of different nitrogen application rates on dry matter accumulation， yield and n fertilizer use efficiency of wheat under fixed ridge cultivation were studied. The results showed that nitrogen fertilizer could significantly promote the growth and development of wheat， and increase the yield and nitrogen use efficiency of wheat. Leaf area index(LAI) and dry matter accumulation were higher in wheat when nitrogen application was 180 kg/hm2. The grain yield was the highest(5 883.3 kg/hm2) . The utilization rate of nitrogen fertilizer was up to 52.10% and the utilization rate of agriculture is 18.77 kg/kg， respectively， which were significantly higher than that of 240 kg/hm2 treatment. In a comprehensive analysis， the optimum nitrogen application rate of wheat was 180 kg/hm2 under fixed ridge cropping in Hexi Oasis Irrigation Area.

S512.1

国家重点研发计划项目(2018YFD0800806)；甘肃省农业科学院科技创新专项(2019GAAS12和2017GAAS25)。