为增强土壤保水续墒，改善土壤质地和团粒结构，提高土壤水分利用效率，以定薯3号为材料，设计玉米秸秆量0、5 000、10 000、15 000、20 000 kg/hm2 5个处理，3次重复，小区面积33 m2(6.0 m×5.5 m)，研究了玉米秸秆还田量对土壤水分含量、容重、马铃薯产量品质及水分利用效率的影响。结果表明，与对照相比，施用秸秆处理的马铃薯块茎中淀粉含量提高0.04～0.92百分点，干物质提高0.18～0.60百分点，商品薯率提高5.2～21.5百分点，产量提高10.68%～54.33%，水分利用效率提高5.93%～30.66%，不同处理对马铃薯产量影响差异显著，施入量为0～15 000 kg/hm2时，马铃薯产量呈上升趋势，超过15 000 kg/hm2产量呈下降趋势，建议推广施用量为15 000 kg/hm2。

In order to improve the soil moisture retention， improve soil texture and aggregate structure， and improve soil water use efficiency， the effects of corn straw returning amount on soil water content， bulk density， potato yield and quality， and water use efficiency were studied， with Dingshu 3 as material， with an experimental design of five treatments of 0 kg/hm2， 5 000 kg/hm2， 10 000 kg/hm2， 15 000 kg/hm2 and 20 000 kg/hm2 of corn straw， three replications and the plot area of 33m2(6.0 m×5.5 m). The results showed that with straw mulching， the starch content， the dry matter content， the commodity potato rate， the potato productivity and the water utilization efficiency of potato tubers increased 0.04～0.92 percent point， 0.18～0.60 percent point， 5.2～21.5 percent point， 10.68%～54.33% and 5.93%～30.66%， respectively， compared with control groups. The effects of different treatments on potato yield were significant. The potato yield showed an upward trend when the application amount ranged from 0 to 15 000 kg/hm2， and a downward trend when it exceeded 15 000 kg/hm2. The recommended application amount was 15 000 kg/hm2.

S532

甘肃省农业科学院院地科技合作项目“旱地马铃薯立旋深松技术研究与示范”(2017GAAS61)；甘肃省引导科技创新发展专项；甘肃省新型肥料创制工程实验室开放基金。