In this study, potted maize was subjected to three grades of soil water content, and we observed and compared stoma density, stoma open, stoma length and width of new developing leaves, and assayed the effects of different soil water content on stomatal conductance, water transpiration consumption and biomass of different organs. The experiment results showed that the decrease of soil water content led to an increase of the stomatal density and a decrease of the stomatal conductance. The reduction of stoma width under soil drought stress was more significant than the length. The mild water stress and medium water stress resulted in a decrease in water transpiration consumption by about 16.3％ and 36.9％, while the biomass decreased by 17.8％ and 40.2％, whereas root/shoot ratio increased by 5.9％ and 17.7％. Under mild water stress and moderate water stress, compared to control, the yield of maize decreased by 3.92％ and 69.6％, while the water use efficiency increased by 13.6％ and decreased 51.8％ respectively. This research indicated that mild soil water stress increased the water use efficiency in the case of no reduction of corn yield, whereas the medium water stress decreased the yield significantly, and tasseling stage is the period at which the daily water consumption was the maximum.%以盆栽玉米为材料,采用三个水分梯度进行处理,显微观察和比较了新生叶的气孔密度、气孔器的长度和宽度、气孔开张度,测定了水分胁迫对气孔导度、植株蒸腾耗水量和各个器官生物量的影响.结果表明:土壤水分含量降低使得玉米叶片气孔密度增大,气孔导度减小,气孔器宽度的降低幅度明显大于长度的降低.轻度和中度土壤水分胁迫使得全生育期单株蒸腾耗水量分别降低16.3%和36.9%,单株生物量分别降低了17.8%和40.2%,根冠比分别增加了5.9%和17.7%,籽粒产量分别减少了3.92%和69.6%,水分利用率分别提高了13.6%和降低了51.8%.因此,轻度的减少水分供应可以在不明显降低产量的情况下提高玉米的水分利用效率,但中度水分胁迫则显著的降低玉米籽粒产量.抽雄期是日蒸腾耗水量最大的时期.
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