外源多胺对低氧胁迫下黄瓜幼苗根系活性氧及保护酶活性变化的影响

Effects of exogenous spermidine on ROS content and antioxidant enzyme activities in root of cucumber seedlings under root-zone hypoxia stress

摘要: 用亚精胺(Spd)处理了低氧胁迫下的黄瓜幼苗，并对根系中的活性氧及保护酶进行了检测。结果表明，低氧处理后黄瓜幼苗根系的脂质过氧化产物丙二醛(MDA)含量显著升高，活性氧生成速率含量和保护酶活性，都有一个先升后降的过程；Spd处理后，低氧胁迫下的黄瓜幼苗根系中的MDA、活性氧含量显著下降，过氧化物歧化酶(SOD)和过氧化物酶(POD)都保持较高的活性，而过氧化氢酶(CAT)活性较弱。超氧阴离子(O^-₂)生成速率的变化与SOD活性的变化有一定的相关性，H₂O₂的含量变化与过氧化物酶(POD)有一定的相关性。

Abstract: The effects of exogenous Spermidine on antioxidant enzyme activities and ROS content in root of cucumber under hypoxia-stress were investigated. The results showed that under hypoxia stress, MDA content obviously increased, ROS content and antioxidant enzyme activities in cucumber seedlings roots increased significantly in the early period of treatment and then decreased in the later period. Exogenous Spd treatment could decrease MAD and ROS contents, maintain greater activities of superoxide dismutase (SOD), peroxidase (POD), while lower catlase (CAT) activity. It indicate the relation between O^-₂ productive rate and SOD activity (R²=0.643～0.7532), as well as H₂O₂ content and POD activity(R²=0.384～0.7705).