钙对紫云英铜害的解毒作用  

Antidotal function of calcium to resist copper toxicity during the Growth of Astragalus Sinicus L.

作　　者：倪才英[1] 曾珩[2] 黄玉源[3] 简敏菲[1] 朱笃[1] 

机构地区：[1]鄱阳湖湿地与流域研究教育部重点实验室//江西师范大学,江西南昌330022 [2]江西省土地开发整理中心,江西南昌330002 [3]仲恺农业工程学院,广东广州510225

出　　处：《生态环境学报》2009年第3期920-924,共5页Ecology and Environmental Sciences

基　　金：国家"973"子项目(2005CCA05100);江西省科技厅重点科技攻关项目([2006]188号)

摘　　要：以南方广泛栽种的绿肥紫云英(Astragalus sinicus L.)为研究对象,尝试研究常用化学肥料中钙离子对铜离子毒害的缓解作用,为此,设计水培实验,研究了不同钙浓度(CK、2000、3000、5000、7000μmol·L-1)对紫云英在铜胁迫下(50μmol·L-1)生长发育的影响。考察指标为生物量、根干质量、地上部干质量、株高、根长、结瘤情况、根色、叶色、地上部及根的铜和钙含量、根和叶中MDA含量等,以探讨钙对铜胁迫下紫云英的植株长势、对铜的吸收和转运以及膜脂过氧化作用的影响。结果表明:钙对遭受铜害的紫云英长势有促进作用,主要表现为根色转淡和生物量、株高、根长增加,而且这种作用随着培养时间的延长和钙浓度的提高愈来愈明显。进一步的分析发现,紫云英根中铜浓度和叶片MDA含量均随着钙浓度提高而显著减少,这说明钙对紫云英铜害的缓解主要是因为钙抑制了紫云英根对铜的吸收和减轻了叶片膜脂过氧化作用所致。该研究结果可为农业上治理土壤铜污染,减轻农作物铜害的影响提供思路和科学依据。Based on a large amount of literature review, this study makes an attempt to investigate calcium＇s function to resist toxicity derived from copper ion during the growth of Astragalus sinicus L., a green manure extensively planted in south China. Water culture experiments are done to study the effects of different calcium concentration （CK, 2 000, 3 000, 5 000, 7 000 μmol·L-1） has on the growth of Astragalu sinicus L. under copper stress （50 μmol·L-1）. The growth indicators include biomass, dry weight of root and shoot, plant height, root length, nodulation, root color, leaf color, contents of the copper and calcium in shoot and root, content of MDA in root and leaf. The purpose of this study is to explore whether calcium has impact on the plant under copper stress, especially on its growth potential, on its uptake and transportation of copper, and on the membrane peroxidation during its growth. The results show that Ca2＋ can facilitate the growth ofAstragalus sinicus L., as is indicated by an increased amount of shoot and root biomass, a growing shoot height and root length, and the fact that root color turned from dark brown to light brown. With the increase of time and Ca2＋ concentration, such ameliorating effect appears more noticeable. Further analysis shows that both Cu2＋ content of the root and MDA content of the leaf reduce significantly as copper concentration increases. This suggests that the reason why calcium is capable of alleviating copper toxicity is that it prevents Astragalus sinicus L. roots from uptaking copper and that it reduces the peroxidation of leaf membrane. The findings of this study may serve as scientific basis to reduce copper contamination in soil, or to alleviate copper stress on crops.

关 键 词：铜毒害 钙 紫云英 MDA 解毒 

分 类 号：X173[环境科学与工程—环境科学]