在大田条件下研究了深耘断根对旱地高产小麦氮素利用及产量的影响 ,结果表明 :冬前深耘断根 ,植株将吸收的氮素较多分配至籽粒 ,分配至根系少 ,肥料氮利用率高 ,土壤残留率和回收率低 ,损失率高 ,产量提高 ;而冬前和起身期都深耘断根与不断根则正好与此相反 ,因而在旱地高产麦田应推广冬前深耘断根 Under field conditions, the effect of deep root cutting on nitrogen utilization and yield of high-yielding wheat in dryland was studied. The results showed that the nitrogen uptake by plant was distributed to the kernel more in winter, High rate of soil residue and recovery rate, the loss rate is high, the yield increased; and winter before and during the deep deep root and roots are just the opposite, so in the dry land high yield wheat field should promote winter deep root