镉、铅及其复合污染对大麦幼苗部分生理指标的影响

Effects of Cd,Pb and Their Combined Pollution on Physiological Indexes in Leaf of the Hordeum vulgare Seedling

以Cd、Pb为胁迫因子,以大麦为试验材料,采用室内培养法,研究了重金属Cd、Pb及复合污染不同时间(3、5 d)对大麦幼苗叶片部分生理指标的影响。结果表明,随着Cd、Pb及Cd+Pb处理浓度的增加,大麦幼苗叶片中可溶性糖的含量表现为先升后降。在Cd、Pb单一处理条件下,不同浓度Cd、Pb均可造成叶细胞膜透性增大,叶片的相对电导率和脯氨酸含量上升。不同浓度的Cd+Pb复合处理对叶细胞膜的损伤均大于单一处理,低浓度Cd+Pb(5+50 mg.L-1)复合处理组的可溶性糖含量比单一处理高。在不同处理时间(3、5 d)内,所有Cd+Pb复合处理组叶中脯氨酸含量均高于单一处理组,Cd、Pb复合处理对脯氨酸的积累有促进作用。单一处理中Cd对大麦幼苗的毒性比Pb大,而复合处理(Cd+Pb)对大麦幼苗的损伤和毒害作用比单一处理更为严重,其交互作用机理值得进一步研究。

Effects of Cd, Pb and their combined pollution on physiological indexes in leaf of the Hordeum vulgare seedling were studied by the indoor cuhivation experiments. The results showed that with the increase of Cd, Pb and Cd ＋ Pb concentrations, content of soluble sugar increased first and decreased afterwards. In Cd,Pb single treatment condition, different concentrations Cd,Pb can make cellular membrane penetration（CMP） in leaf increase, relative conductance of leaf exosmosis liquids and content of proline ascended. Damnification of Cd ＋ Pb combined treatment on CMP was higher than those of Cd, Pb single treatment, effect of low concentrations （5 ＋ 50 mg·L^-1 ） combined treatment on content of soluble sugar was higher than those of Cd, Pb single treatment. In different treatment time （3, 5 d）, Effects of all Cd ＋ Pb combined treatment on content of proline in leaf were higher than those of Cd, Pb single treatment, toxicity of Cd in H. vulgare seedling was higher than that of Pb. However, toxicity of Cd ＋ Pb combined treatment in H. vulgare seedling was higher than that of Cd, Pb single treatment, interaction mechanism of Cd, Pb was deserved further study.