外源有机酸对马蔺幼苗生长、Cd积累及抗氧化酶的影响  

Effects of exogenous organic acids on the development,Cd accumulation and antioxidative enzyme of Iris lactea var. chinensis

作　　者：原海燕[1] 黄苏珍[1] 郭智[1] 韩玉林[1] 

机构地区：[1]江苏省中国科学院植物研究所(南京中山植物园),江苏南京210014

出　　处：《生态环境》2007年第4期1079-1084,共6页Ecology and Environmnet

基　　金：国家自然基金资助项目(30270940);江苏省农业高新技术项目(BG2003308)

摘　　要：植物修复环境重金属污染仍然受多种因素制约,而通过有机酸辅助植物修复技术提高修复效率逐渐成为治理重金属污染的有效途径之一。采用溶液培养研究了Cd胁迫下2种不同浓度外源有机酸EDTA、柠檬酸对马蔺(Iris lactea var.chinensis)幼苗生长、Cd积累及抗氧化保护酶的影响。结果表明,与单独Cd胁迫(CK)相比,Cd胁迫下溶液中添加0.5和5mmol·L-1EDTA和相同浓度柠檬酸后马蔺地上部Cd质量分数无明显变化,而马蔺地下部Cd质量分数显著增加,0.5mmol·L-1低浓度EDTA和柠檬酸分别使马蔺根系Cd质量分数比对照增加55.6%、137.1%,柠檬酸的促进效果较明显。而溶液中添加2种有机酸对马蔺生物量的影响与对马蔺吸收Cd的效应不同,EDTA和柠檬酸使马蔺地上部生物量略有下降,但与对照相比差异不显著,而5mmol·L-1高浓度EDTA、柠檬酸使根系生物量明显下降,分别比对照下降17.2%、25.7%。同时,2种不同浓度有机酸均使马蔺叶片MDA含量增加,而马蔺叶片SOD和POD酶活性的增加表明马蔺体内抗氧化保护能力的增强,一定程度上可减轻氧化胁迫对马蔺造成的伤害。实验结果说明EDTA和柠檬酸对促进马蔺修复Cd污染具有一定的潜力。　The remediation of heavy metal-contaminated sites using plants was limited by many factors at present. However,the improving of efficiency of phytoremediation by means of organic acid become an effective way to alleviate the pollution of heavy metal. The Effectss of two exogenous organic acids on the development,Cd accumulation and antioxidant enzymes of Iris lactea var. chinensis under Cd stress was carried out by hydropinic culture. The results showed that Cd contents in the shoots of Iris lactea var.chinensis treated with 0.5 and 5 mmol·L^-1 EDTA and citric acid were no obvious difference with the control,while Cd contents in the roots increased significantly at same treatments. Cd contents in the roots exposed to 0.5 mmol·L^-1 EDTA and citric acids increased by 55.6%and 137.1%,respectively,than that of control. While the effects of two organic acids on the shoot dry weight and Cd contents in shoots and roots were different. The shoot dry weights of Iris lactea var. chinensis in all the treatments of organic acids decreased not obviously different compared with that of control,while root biomass under 5 mmol·L^-1 organic acids reduced significantly and decreased by 17.2% and 25.7%,respectively. Malondialdehyde （MDA） contents in the shoots were increased in all treatments of organic acids compared with control. The increases of activities of superoxide dismutase （SOD） and peroxidase（ POD） treatments of organic acids showed the strengthen of antioxidant protective ability and relieving the harm caused by oxidant stress. So,EDTA and citric acids have potential ability to promote the remediation the pollution of Cd using Iris lactea var. chinensis.

关 键 词：马蔺(Iris lactea var.chinensis) CD EDTA 柠檬酸 抗氧化物酶 

分 类 号：X173[环境科学与工程—环境科学]