调亏灌溉对于玉米生理指标及水分利用效率的影响

Effects of Regulated Deficit Irrigation on Physiological Indices and Water Use Efficiency of Maize

依据在渭北黄土高原区的大田玉米调亏灌溉试验资料，分析了不同亏水处理对光合速率、气孔导度，蒸腾速率、根冠比、产量与耗水量以及水分利用效率等因素的影响，从亏水处理引起的气孔反应能提高光合与蒸腾之比，揭示了调亏灌溉的节水增产机理。最后，从既提高产量又提高水分利用效率的双重目的出发，得到了苗期土壤含水率为５０％～６０％田间持水量、拔节期土壤含水率为６０％～７０％田间持水量是最佳的调亏灌溉方案。

This paper analyzed the effect of Regulated Deficit Irrigation(RDI) on photosynthesis,transpiration,stomatal conductance, the ratio of dry root weight to the matter weight above ground, yield and consumptive use of water as well as water use efficiency of maize in the field. It reveals the mechanism of yield improved using the optimum RDI regime by which the change of stomatal behavior can improve the ratio photosynthesis and transpiration. The experiment result demonstrated that the moderate water stress in seedling (soil moisture content is 50 %￣60 % of field capacity) and the light water stress in jointing stage (soil moisture content is 60 %￣70 % of field capacity) is considered as the optimum irrigation schedule in order to obtain high yield and high water use efficiency.