旱地春小麦对有限灌水高效利用的研究

High Efficient Use of Limited Irrigationn Water by Dryland Spring Wheat

在宁夏南部半干旱山区的研究结果表明，满足籽粒产量最大时所需的补充灌水量为２００ｍｍ；满足作物水分利用效率最高时所需的补充灌水量为１００ｍｍ；满足灌水效率最高时所需的补充灌水量为６０ｍｍ。６０ｍｍ补充灌水条件下可使春小麦的耗水量从２４０ｍｍ增加到３２０ｍｍ左右，同时明显地使作物产量、水分利用率和灌水效率得以同步提高，作物对土壤储水的利用程度也相应增强。据此认为，旱地春小麦有限灌水量的适宜下限为６０ｍｍ。对不同生育期有限灌水的研究结果表明，拔节期是春小麦有限供水的最佳时期。

Theresearchresultsshowedthatinthesemiaridmountainareaofthe Southpart of Ningxia ,the maximum supplementary irrigation water to meet withthe highest grain yields of spring wheat was 200 mm;and the supplementary irrigation wa- ter to satisfy the highest crop water use efficiency was 100 mm;and the supplementary irrigation water required to satisfy the highest irrigation efficiency was 60 mm. In the case of 60 mm supplementary irrigation water,the water consumption of spring wheat increased from 240 mm to 320 mm or so. Meanwhile,crop water consumption,water use efficiency and irrigation efficiency were much improved synchronously.And also,stored soil water use efficiency by crops was improved correspondingly, on the basis of which it can be considered that the limited irrigation water for dryland spring wheat was the lower limitation. Also,the results from research on the limited irrigation water in different and developing stages indicated that the best period of limited water supply should be the jointing stage.