中文摘要：

以黑种皮大豆（黑豆）和黄种皮大豆（黄豆）为材料，在水培条件下用聚乙二醇（PEG）模拟干旱胁迫处理大豆，分析大豆叶片生理特性和质膜H^＋-ATP酶活性的变化。结果表明：2％、5％和10％PEG处理条件下，随处理浓度和时间的增加，2种大豆植株失水率上升，叶片蒸腾速率降低，气孔传导率下降。在所有相同处理条件下，黄豆植株失水率小于黑豆，而叶片蒸腾速率和气孔传导率下降幅度大于黑豆，说明黄豆的耐旱性较黑豆强。在相同处理下黄豆叶片可溶性蛋白、可溶性糖含量高于黑豆，而黑豆叶片中游离脯氨酸含量高于黄豆；在抗氧化酶体系中，黄豆叶片过氧化氢酶（CAT）活性下降幅度显著快于黑豆，其叶片中H2O2含量高于黑豆，干旱胁迫下黄豆叶片质膜H^＋-ATPase磷酸化水平及其与14-3-3蛋白的结合受到的抑制较黑豆强。这说明，黄豆主要通过增加可溶性蛋白、可溶性糖含量以及调节抗氧化酶系活性增强耐旱性，而黑豆通过调节H^＋-ATPase活性增强其耐旱性。

英文摘要：

Using a black soybean （BS） cultivar and a yellow soybean （YS） cultivar as the materials, changes in physiological characteristics and function of plasma membrane （PM） H^＋-ATPase were analyzed in the two soybean cultivars treated with polyethylene glycol （PEG） simulation drought stress under hydroponic conditions. The results indicated that under the treatment conditions of 2 %, 5 % and 10 % PEG, with an increase in PEG concentration and treatment time, an elevation in the water loss rate, a decrease in leaf transpiration rate and stomatal conductance were observed in the two soybeans. Under all the same treatment conditions, the water loss rate in YS was lower than that of BS, whereas, the reduction in YS leaf transpiration rate and stomatal conductance was larger than those of BS, indicating that the tolerant ability of YS to drought stress was stronger than that of BS. Under the same treatment conditions, the leaf soluble protein and soluble sugar content in YS was higher than those in BS while the leaf free proline content in BS was higher than that in YS. In the antioxidant enzyme system, the decrease speed in CAT activity in YS leaves was significantly faster than that in BS, leading to a higher H2O2 content in YS leaves than that in BS leaves. As a result, under drought stress conditions, the inhibition in the PM H^＋-ATPase phosphorylation level and its interaction with 14-3-3 protein in YS leaves was stronger than those in BS leaves. The PM H^＋-ATPase and proton pump activity in YS leaves were lower than those in BS leaves. Consequently, the stomata aperture in YS leaves was less than that in BS leaves. Leaf transpiration rate and stomatal conductivity in YS were lower than those in BS leaves. This might be an important mechanism underlying the stronger drought tolerance in YS. Soybean is mainly enhance its drought resistance by the means of increasing permeability material soluble protein, soluble sugar and regulating the activity of antioxidant enzyme system.