干旱胁迫及复水对豌豆苗期保护酶活性及膜脂过氧化的影响

Effect of drought stress and rewater on protective enzyme activity and membrane lipid peroxidation in pea leaves during seedling stage

采用盆栽控水试验法,研究了干旱胁迫及复水对豌豆苗期叶片超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性及丙二醛(MDA)含量、质膜相对透性(RC)的影响,对豌豆苗期抗氧化能力进行了综合评价。结果表明:干旱胁迫降低了SOD活性,随胁迫程度加重和历时延长降幅增大。轻度干旱胁迫10 d或重度干旱胁迫提高了POD和CAT活性,随胁迫程度加重和历时延长增幅加大。复水5 d对CAT、SOD活性产生部分补偿效应,对POD活性产生等量补偿效应。复水10 d对SOD活性产生等量补偿效应,对CAT、POD活性产生等量或超补偿效应;干旱胁迫增加了MDA含量,随胁迫程度加重增幅加大、胁迫历时延长增幅减少。复水5 d、10 d对干旱胁迫5 d豌豆叶片MDA含量分别产生部分和等量补偿效应。干旱胁迫导致膜脂透性增大,随胁迫程度加重和历时延长增幅加大。复水5 d、10 d可分别产生部分和等量补偿效应。

A pot experiment was conducted to investigate the effect of soil water on protective enzymes of superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD） activity, and as well as on membrane lipid peroxidation in- eluding malonaldehyde （MDA） content and plasma membrane permeability （RC） in pea （Pisum sativum Linn. ） leaves during seedling stage under drought stress and rewater conditions. The comprehensive evaluation on antioxidant capability of pea during seedling stage was also made. The results showed that drought stress declined SOD activity, and more re- markably with increasing stress intensity and time. Light drought stress for 10 d and serious drought stress all increased POD and CAT activity, and more obviously with increasing stress intensity and time. Rewater for 5 d produced partial compensation to CAT and SOD activity, and equal compensation to POD activity. Rewater for 10 d produced equal compensation to SOD activity and equal or over compensation to CAT and POD activity. Drought stress increased MAD content, and increased more with increasing stress intensity, and increased less with time. Rewater for 5 d and 10 d pro-duced partial and equal compensation respectively to MDA content of pea leaves under drought stress for 5 d. Drought stress enhanced RC and more significantly with increasing stress intensity and time. Rewater for 5 d and 10 d produced partial and equal compensation respectively.