水分胁迫对3种苗木叶片渗透调节物质与保护酶活性的影响

Effects of Water Stress on Osmotic Adjustment and Activity of Protect Enzymes in the Leaves of Three Sorts of Seedlings

以1 a生刺槐(Robinia pseudoacacia)、元宝枫(Acer truncatum)和侧柏(Platycladus ori-entalis)苗木为材料,通过盆栽控水试验研究了水分胁迫对3种苗木叶片丙二醛含量、渗透调节物质和保护酶活性的影响,并探讨了这些生理指标与其抗旱性的关系。结果表明,随胁迫强度增大,3种苗木的渗透调节物质游离脯氨酸和可溶性糖含量增加,而可溶性蛋白含量降低;丙二醛(MDA)含量随水分胁迫程度的加剧呈递增趋势;超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性随干旱强度增大,开始增加,而在重度胁迫时,酶活性下降,但水分胁迫时的酶活性始终高于正常水分时。

Effects of water stress on the content of malondialdehyde （MDA）, osmotic adjustment and protect enzymes in the leaves of one-year-old Robinia pseudoacacia, Acer truncatum and Platycladus orientalis seedlings were studied to determine the relationship between the physiological indices and drought resistance. The results indicated that with the aggravation of water stress, the content of free proline and soluble sugar in the leaves of the three seedlings increased, whereas that of soluble protein decreased; the content of malondialdehyde （MDA） in the leaves tended to be increased with the aggravation of water stress. The activities of superoxide dismutase （SOD）, catalase （CAT）and peroxidase （POD） with the aggravation of water stress increased at beginning and then dropped under severe water stress, but the activities of three protect enzymes were always higher than those under normal water condition.