重金属污染胁迫对杂交狼尾草生理生化特性的影响

Effect of heavy metal stress on physiological and biochemical characteristics of Hybrid Pennisetum

为了探讨杂交狼尾草(Pennisetum americanum×P.purpureum)的耐重金属性,用杂交狼尾草为试验材料,就不同程度重金属污染胁迫对其叶片中叶绿体色素、可溶性蛋白质、丙二醛(MDA)质量浓度,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性以及叶膜电解质相对渗透率的影响进行了研究.结果表明,随着重金属胁迫的加重,杂交狼尾草叶片中的叶绿体色素、可溶性蛋白质质量浓度呈下降趋势,MDA质量浓度和叶膜电解质相对渗透率呈上升趋势,SOD、CAT和POD活性呈先上升后下降趋势.轻度重金属污染胁迫对杂交狼尾草生理生化指标影响不显著,中、重度重金属污染胁迫下其仍然可以生长,表明杂交狼尾草对重金属污染有一定的耐受性,其可被用作重金属复合污染地区土壤的修复植物.

In order to investigate the resistance of Hybrid Pennisetum to heavy metals , the mass concen-trations of chloroplast pigments , soluble protein and malondialdehyde （ MDA） , the activities of superox-ide dismutase （SOD）, peroxidase （POD） and catalase （CAT）, and the electrolyte relative permeabili-ty of leaf membrane were studied by using Hybrid Pennisetum as the experimental materials treated by different degree of heavy metal stress .The results showed that the mass concentrations of chloroplast pig-ments and soluble protein were decreased , the MDA mass concentration and the electrolyte relative per-meability of leaf membrane were increased , and that the activities of SOD , POD and CAT were increased first and decreased later with the aggravation of heavy metal stress .The physiological and biochemical in-dexes of Hybrid Pennisetum were not affected significantly under light heavy metal stress .It still could be grown under moderate and severe heavy metal stress , showing a certain degree of tolerance .Hybrid penn-isetum can be used as remediation plant in heavy metal compound pollution area .