干旱胁迫对麻疯树幼苗抗氧化代谢的影响

Effects of Drought Stress on Antioxidant Metabolism of Jatropha curcas Seedlings

采用盆栽控水的方法,研究了不同程度干旱胁迫下麻疯树幼苗叶片相对含水量(LRWC)、质膜透性、相对电导率(REC)、丙二醛(MDA)含量及抗氧化酶活性的变化。结果表明,麻疯树幼苗叶片相对含水量随胁迫时间的增加呈极显著(p<0.01)下降趋势;相对电导率、丙二醛含量随胁迫时间的增加而呈极显著(p<0.01)增加趋势,胁迫初期和中期二者增加幅度相对较小,胁迫后期急剧增加;超氧化物歧化酶(SOD)活性随胁迫时间的增加而持续升高,过氧化物酶(POD)活性和过氧化氢酶(CAT)活性随胁迫时间的增加呈先升高后下降的趋势,在W 7(干旱35d)时POD和CAT活性达到最大值。

Pot experiment was carried out to study the leaf relative water content （LRWC） , membrane permeability of cell, malondialdehyde （MDA） content and antioxidase activity of Jatropha curcas seedlings under different degrees of drought stress. The results showed that LRWC decreased significantly （p 〈 0. 01 ） with the increment of stress and relative conductivity and MDA content increased significantly （p 〈 0. 01 ）. The increasing was relatively small in both the early and mid-stress, there was a sharp increase in the post-stress. Superoxide dismutase （SOD） activity continued to rise with the increase of stress time. Peroxidase （POD） activity and peroxide catalase （CAT） activity increased with the lapse of stress time until in the W7 （ drought for 35 days） where they reached the peak of activity ,followed by a sharp reduction of the protective antioxidant enzyme system in the W7 maximum capacity.