锌对小麦抗氧化酶活性的影响

Effect of Zinc on the Antioxidase Activity in Wheat

[目的]探讨内源抗氧化酶系统在作物抵抗外源重金属胁迫中的作用。[方法]用不同浓度锌溶液处理盆栽小麦幼苗,至幼苗生长缓慢时取材测定过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、丙二醛(MDA)等指标。[结果]20、50、100、200、400和800mg/L锌溶液处理的小麦POD活性分别比对照组提高了54.8%、58.2%、115.2%、157.8%、408.5%和564.0%。200、400和800mg/L锌溶液处理的小麦SOD活性分别是对照组的77.1%、68.4%和61.2%。20、50、100、200和400mg/L锌溶液处理的小麦CAT活性分别比对照组提高了1.7%、4.0%、13.2%、16.3%和22.8%。20和50mg/L锌溶液处理的小麦的丙二醛含量分别为对照的96.4%和97.5%。100、200、400和800mg/L锌溶液处理的小麦的丙二醛含量分别比对照组提高了57.7%、92.7%、235.4%和464.4%。[结论]在锌胁迫下的小麦活性氧清除系统中,POD是关键的抗氧化酶。

[Objective] The purpose of this research was to discuss the action of endogenous antioxidase system in resistance of crops to exogenous heavy metal stress.[Method] The potted wheat seedlings were treated with different concn.of zinc（Zn2＋）solution till the seedlings grew slowly,then the materials were fetched for determining the indexes,such as peroxidase（POD）,superoxide dismutase（SOD）,catalase（CAT）and malondialdehyde（MDA）.[Result] Compared with CK group,the POD activities in wheat treated with 20,50,100,200,400 and 800 mg/L Zn2＋ solution were enhanced by 54.8%,58.2%,115.2%,157.8%,408.5% and 564.0% resp.;the SOD activities in wheat treated with 200,400 and 800 mg/L Zn2＋ solution were 77.1%,68.4% and 61.2% resp.;the CAT activities in wheat treated with 20,50,100,200 and 400 mg/L Zn2＋ solution were enhanced by 1.7%,4.0%,13.2%,16.3% and 22.8% resp.;the MDA contents in wheat treated with 20 and 50 mg/L Zn2＋ solution were 96.4% and 97.5% resp.;the MDA contents in wheat treated with 100,200,400 and 800 mg/L Zn2＋ solution were enhanced by 57.7%,92.7%,235.4% and 464.4% resp.[Conclusion] In the scavenging system of active oxygen in wheat under Zn2＋ stress,POD was key antioxidase.