限量灌溉对冬小麦抗旱增产和水分利用的影响

Effects of Limited Irrigation upon Yield Increase in Wheat by Drought Resistance and Water Use

在渭北旱塬长武试验基点进行了三年冬小麦限量灌溉的田间试验。结果表明,底墒状况对冬小麦苗期生长、抗旱增产和水分利用效率的影响特别大。底墒不足的干旱年份,如有条件,应进行限量灌溉使1m土层的有效水含量达到130mm以上,根系用水层的底墒蓄积总量超过350mm,低于这一水平,产量将锐减。一般情况下,拔节孕穗阶段的生长期灌溉效果不如播前灌溉。

Field trials of limited irrigation on winter wheat was carried out in Changwu Ex-periment base on the Rainfed Weibei Highland in three years.The results indicated thatbase soil moisture had a great bearing upon wheat growth in the stage seedling,yield in-crease by drought resistance and water use efficiency.In the dry years with shortage ofbase soil moisture,in case of limited irrigation conducted,the available water contents inone-meter soil layer reaches over 130 mm,and base water content stored in water uselayer by root system is over 350 mm,wheat yield increases greatly,while below this waterlevel,wheat yield decreases significantly.In common case,the effects of irrigation in thegrowing stage of shooting and elogation is no better than that before planting.