施肥深度对旱地小麦氮素利用及产量的影响

本文用土柱栽培法研究了施肥深度对旱地小麦氮素利用及产量的影响 ,结果表明 :较深层次 (2 0～ 40cm)施肥 ,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 ,土壤残留率和损失率少 ,回收率高 ,从而提高了产量 ;施肥过浅 (0～2 0cm)和施肥过深 (6 0～ 80cm)则相反 ,由此可以认为旱地小麦最佳施肥深度应在 2 0～ 40cm左右 ,可据此制定施肥管理方案 ,以获得高产高效。

EFFECTS OF FERTILIZER APPLICATION DEPTH ON NITROGEN UTILIZATION AND YIELD IN DRY LAND WHEAT

The effects of fertilizer application depth on nitrogen utilization and yield of wheat in dry land have been studied by using soil column method. The results showed that with fertilizer applying in subsurface layer of 20～40cm more nitrogen absorbed was distributed in kernel and less in root system, the utilization ratio and recovery ratio of fertilizer nitrogen increased, the ramainder ratio in soil and loss ratio of fertilizer nitrogen decreased, and yield of wheat increased. However, when the fertilizer applied in surface layer of 0～20cm and deep layer of 60～80cm, the results were contrary. It is concluded that the depth of 20～40cm fertilizer application is the best for gainning higher yield and nitrogen fertilizer utilization efficiency in dry land wheat.