Changes of activated oxygen O2 and H2O2, malondialdehyde (MDA) content and activity of enzymes involving cell defense in leaves of Korean pine (Pinus koraiensis Sieb. et. Zucc) seedling under different time of low temperature stress were studied. With the increase of stress time，the rate of O2 generation and H2O 2 content increased to a certain degree and then decreased. The increase of MDA content fluctuated as well as its decrease after the low-temperature stress was removed. The activity of cell defense enzymes, viz. superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascrobate peroxidase (ASP) were gradually decreased. However, after cold pre-treatment of the seedlings all these indexes showed marked changes and different ways of adaptivity to cold stress; thus enhanced the cold tolerance of the plant.
低温胁迫下红松幼苗活性氧的产生及保护酶的变化
李晶 阎秀峰 祖元刚*
（东北林业大学森林植物生态学开放研究实验室， 哈尔滨150040）
摘要：在不同低温胁迫时间下 ,对红松 (Pinuskoraiensis Sieb .et.Zucc)幼苗针叶中H2 O2 、O-·2 、膜脂过氧化产物丙二醛 (MDA)、组织自动氧化速率及保护酶超氧化物歧化酶 (SOD)、过氧化物酶 (POD)、过氧化氢酶 (CAT)和抗坏血酸过氧化物酶 (ASP)的动态变化过程进行了测定。结果表明 ,随着低温胁迫时间的延长 ,O-·2 产生速率和H2 O2 含量先上升后下降 ;MDA的含量呈波动性增加 ,解除低温胁迫后的组织自动氧化速率波动性下降 ;保护酶SOD、POD、CAT及ASP酶活性均逐渐下降。经过低温锻炼 ,植株上述各项指标均发生明显变化 ,并以各自不同的方式增加对低温的适应性 ,抗寒能力明显提高。
关键词： 红松幼苗；低温胁迫；活性氧；保护酶；丙二醛；组织自动氧化速率
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