水分胁迫下钙对大豆叶片膜脂过氧化程度的影响

Effect of Calcium on the Membrane Lipid Peroxidation of Soybean Leaes Under Water Stress

用控制营养钙量（0、5、14mmol／L）的方法，培养大豆幼苗，以获得3种钙水平的大豆叶片作为材料，研究水分胁迫（－0．5MPa）下，不同钙水平大豆叶片中质膜透性、膜脂过氧化程度以及膜脂脂肪酸的组成、脂肪酸不饱和指数的变化。结果表明：水分胁迫下，细胞质膜透性增大，以缺钙叶片变化幅度最大，MDA含量的变化趋势与膜透性变化一致．叶片内源抗氧化物质ASA随胁迫时间延长，其含量逐渐下降，但高钙叶片ASA一直维持在较高水平．无论正常供水还是水分胁迫下，钙处理的饱和脂肪酸含量均降低，而不饱和脂肪酸含量增加。

The soybean seedlings grown in the solution with different calcium concentration (0, 5, 14mmol· L-1) were used to study the effects of water stress on the plasma membrane permeability (PMP),membrane lipid peroxidation and composition of membrane lipid and the index of unsaturated fatty acid (IUFA). The results showed that under water stress, the PMP of [ Ca2+] -treated leaves increased and no - Ca2+ -treaed had the greatest change in PMP. The contents of MDA changed in the same tendency as PMP. ASA content deceased gradually witLh water stress, but the highest ASA content was observed in the high Ca2+ treated leaeves. linolenic acid content of leaves was decreased hy Ca2+ treatment, but palmitic acid content and IUFA increased under both conditions.