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在植物生长箱与田间条件下研究了冻害和热害对油菜植株抗氧化酶活性、脂质过氧化及膜损伤的影响．冻害处理使油菜叶片膜脂不饱和程度提高，而热害则使膜脂不饱和程度下降．冻害能使叶片ＳＯＤ活性显著提高，而ＣＡＴ与ＰＯＤ活性下降；热害则使叶片ＳＯＤ与ＰＯＤ活性下降，而对ＣＡＴ活性影响不大．冻害或热害处理均能提高油菜内源游离脯氨酸含量、电解质外渗率及脂质过氧化作用，而叶片叶绿素含量与根系活力则显著下降．热害和冻害引起的叶片脂肪酸组分变化、抗氧化酶活性与膜完整性的丧失以及叶绿素的降解，表明植株体内有氧自由基积累，从而引起植物伤害．冻害处理的油菜能缓慢地恢复生长，而热害处理的植株生长较差，热害处理两个月后逐渐死亡．
Effects of frost damage and heat damage on antioxidant enzyme activities, lipid peroxidation and membrane damage of rapeseed plants were studied under plant growth chamber and field conditions. Frost damage treatment rape leaves membrane lipids increased the degree of unsaturation, while the heat harm is the degree of membrane lipids decreased. Frost damage can significantly increase the SOD activity of leaves, while the activities of CAT and POD decrease. However, the activities of SOD and POD decrease while the activities of CAT decrease. Frost damage or heat injury treatment could increase endogenous free proline content, electrolyte extravasation rate and lipid peroxidation, while the content of chlorophyll and root activity decreased significantly. Changes in fatty acid composition, loss of antioxidant enzyme activity and membrane integrity, and chlorophyll degradation caused by heat injury and frost damage indicate the accumulation of oxygen free radicals in the plant, causing plant damage. Frost damage treatment of rapeseed can slowly restore growth, and heat treatment plant growth is poor, heat treatment gradually died after two months.