Hg~(2+)胁迫对菠菜幼苗叶绿素含量及抗氧化酶活性的影响

目的]探讨Hg2+胁迫与植物体内抗氧化酶变化的关系。方法]将菠菜种植于Hg2+浓度为5、152、5、35、45 mg/L的处理液中,研究Hg2+胁迫对菠菜幼苗叶绿素含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)及过氧化氢酶(CAT)活性的影响。结果]随着Hg2+浓度的增加,菠菜幼苗叶绿素含量总体呈减少趋势,当Hg2+浓度为5 mg/L时,叶绿素含量最大,为0.79 mg/g。随着Hg2+浓度的增加,SOD、POD、CAT活性呈先升后降趋势,当Hg2+浓度为15 mg/L时,SOD、POD、CAT活性达到最大值,分别为95.2 U/ml、0.24△OD470/(g.min)、0.11△OD240/(g.min)。结论]在逆境环境因子作用下,植物体通过自身的酶机制,可以对外界不良环境作出保护性反应。

Effects of Water Pollution Caused by Hg2 on the Chlorophyll Content and Antioxidase Activity in Spinach Seedlings

Objective] The research aimed to discuss the relationship between Hg2+ stress and the change of antioxidase in plant.Method] The spinaches were planted in treatment solutions with Hg2+ concn.at 5,15,25,35 and 45 mg/L to research the effects of Hg2+ stress on the chlorophyll content and the activities of superoxide dismutase(SOD),peroxidase(POD) and catalase(CAT) in spinach seedlings.Result] As Hg2+ concn.was increased,the chlorophyll content in spinach seedlings showed reducing trend totally and when it was 5 mg/L,the chlorophyll content was biggest,being 0.79 mg/g.As Hg2+ concn.was increased,the activities of SOD,POD and CAT showed first increasing and then decreasing trend and when Hg2+ was 15 mg/L,their activities reached their maximum values,being 95.2 U/ml,0.24 △OD470/(g·min) and 0.11 △OD240/(g·min) resp.Conclusion] Under the action of adversity environmental factors,the plant could make protective reaction to external bad environment through its own enzyme mechanisms.