水分胁迫对元宝枫膜脂过氧化作用的影响

Effect of Water Stress on Menbrane Lipid Peroxidation in Maple

采用盆栽控水法和ＰＥＧ６０００处理法研究了在水分胁迫条件下元宝枫膜脂过氧化作用的变化与抗旱性的关系，结果发现，随胁迫时间的延长和胁迫程度的加深，ＭＤＡ含量和质膜相对透性逐渐增大，但在轻度和中度水分胁迫条件下增幅不显著。ＳＯＤ和ＣＡＴ活性随胁迫程度加深缓慢降低，但在同一胁迫程度下随时间延长，两种酶活性呈增高趋势，并逐渐接近正常水平。这表明元宝枫对干旱有较强的适应能力，在缺水条件下体内的保护酶仍能维持较高的活性水平，减轻了由膜脂过氧化引起的膜伤害。

Relationship between membrane lipid peroxidation and drought resistance of maple(Acer truncatum) was studied through one year old pot cultured seedlings growing under different soil water contents and seven year old trees treated with different water potential solution of PEG6000.The results showed that the lengthening and deepening of water stress,permeability of plasma membrane and content of MDA increased gradually,but the increase was not remarkable under light and moderate water stress.The activity of SOD and CAT decreased slowly with the deepening of water stress,while under the same grade of water stress,SOD and CAT activity increased with lengthening of water stress and near normal level finally.This indicated that the maple has a powerful adaptability to drought.Under water stress the protective enzymes could maintain a relatively high activity and eased the damage of membrane caused by lipid peroxidation.