Zn^(2+)和Hg^(2+)对小麦幼苗某些生理生化指标的影响

Effects of Zn^(2+) and Hg^(2+) on Some Physiological and Biochemical Indices of Wheat Seedling

[目的]为研究Zn和Hg对植物的毒害机理提供理论依据。[方法]以辽春14小麦为材料,研究不同浓度Zn2+(0、10、50、100、200、400 mg/L)和Hg2+(0、10、20、40、80、120 mg/L)对其生理特性的影响。[结果]10、50、100、200、400 mg/L Zn2+处理的小麦叶片SOD活性分别为对照的115.93%、98.90%、126.37%、141.21%、157.14%,叶绿素和可溶性蛋白质含量均显著降低;10 mg/L Zn2+处理的小麦叶片MDA含量低于对照;随着Zn2+浓度的升高,POD活性呈升高趋势。随着Hg2+浓度的增大,叶绿素含量呈下降趋势,SOD和POD活性总体呈升高趋势;40 mg/LHg2+处理的小麦叶片可溶性蛋白质含量与对照差异最大,为对照的79.15%;10 mg/L Hg2+处理的小麦叶片MDA含量为对照的70.85%。[结论]随Zn2+和Hg2+浓度增加,小麦细胞膜损伤加重,SOD和POD活性升高。

[ Objective ] The aim was to provide the theoretical basis for the study on toxicity mechanism of Zn and Hg on plants. [ Method ] With wheat variety Liaochun 14 as the material, the effects of Zn^2＋ with different concn. [0 （CK）, 10, 50, 100,200,400 mg/L]and Hg^2＋ with different concn. [0（CK）, 10, 20, 40, 80, 120 mg/L] on its physiological characteristics were studied. [ Result] The SOD activities of wheat leaves in treatments with Zn^2＋ at 10, 50, 100,200,400 mg/L were 115.93% , 98.90% , 126.37%, 141.21%, 157.14% of that of CK resp. , and the contents of chlorophyll and soluble protein was decreased significantly. The MDA content in treatment with Zn^2＋ at 10 mg/L was lower than that of CK. With the increase of Zn^2＋ concn., the POD activity showed an increasing trend. With the increase of Hg^2＋ conch. , the chlorophyll content showed descending trend and the activities of SOD and POD generally showed an increasing trend. The soluble protein content in wheat leaves in treatment with Hg^2＋ at 40 mg/L had the biggest difference with that of CK, being 79.15% of that of CK. The MDA content in wheat leaves in treatment with Hg^2＋ at 10 mg/L was 70.85% of that of CK. [ Conclusion] With the increase of Zn^2＋ and Hg^2＋ conch. , the injury of wheat cell membrane was aggravated, and the activities of SOD and POD was increased.