Improved cadmium uptake and accumulation in the hyperaccumulator Sedum alfredii:the impact of citric acid and tartaric acid  

作　　者：Ling-li LU Sheng-ke TIAN Xiao-e YANG Hong-yun PENG Ting-qiang LI 

机构地区：[1]Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health,College of Environmental and Resource Sciences,Zhejiang University

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2013年第2期106-114,共9页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：Project supported by the National Natural Science Foundation of China(No.31000935);he Fundamental Research Funds for the Central Universities(No.2012FZA6008);the Department of Science & Technology of Zhejiang Province(No.2011C22077),China

摘　　要：The elucidation of a natural strategy for metal hyperaccumulation enables the rational design of technologies for the clean-up of metal-contaminated soils.Organic acid has been suggested to be involved in toxic metallic element tolerance,translocation,and accumulation in plants.The impact of exogenous organic acids on cadmium(Cd) uptake and translocation in the zinc(Zn)/Cd co-hyperaccumulator Sedum alfredii was investigated in the present study.By the addition of organic acids,short-term(2 h) root uptake of 109 Cd increased significantly,and higher 109 Cd contents in roots and shoots were noted 24 h after uptake,when compared to controls.About 85% of the 109 Cd taken up was distributed to the shoots in plants with citric acid(CA) treatments,as compared with 75% within controls.No such effect was observed for tartaric acid(TA).Reduced growth under Cd stress was significantly alleviated by low CA.Long-term application of the two organic acids both resulted in elevated Cd in plants,but the effects varied with exposure time and levels.The results imply that CA may be involved in the processes of Cd uptake,translocation and tolerance in S.alfredii,whereas the impact of TA is mainly on the root uptake of Cd.The elucidation of a natural strategy for metal hyperaccumulation enables the rational design of tech- nologies for the clean-up of metal-contaminated soils. Organic acid has been suggested to be involved in toxic metallic element tolerance, translocation, and accumulation in plants. The impact of exogenous organic acids on cadmium （Cd） uptake and translocation in the zinc （Zn）/Cd co-hyperaccumulator Sedum alfredii was investigated in the present study. By the addition of organic acids, short-term （2 h） root uptake of ^109Cd increased significantly, and higher ^109Cd contents in roots and shoots were noted 24 h after uptake, when compared to controls. About 85% of the ^109Cd taken up was distributed to the shoots in plants with citric acid （CA） treatments, as compared with 75% within controls. No such effect was observed for tartaric acid （TA）. Reduced growth under Cd stress was significantly alleviated by low CA. Long-term application of the two organic acids both resulted in elevated Cd in plants, but the effects varied with exposure time and levels. The results imply that CA may be involved in the processes of Cd uptake, translocation and tolerance in S. alfredii, whereas the impact of TA is mainly on the root uptake of Cd.

关 键 词：HYPERACCUMULATION CADMIUM Organic acid Sedum alfredii TRANSLOCATION UPTAKE 

分 类 号：X173[环境科学与工程—环境科学]