Zinc adsorption and desorption characteristics in root cell wall involving zinc hyperaccumulation in Sedum alfredii Hance.
- Author:
Ting-qiang LI
1
;
Xiao-e YANG
;
Fan-hua MENG
;
Ling-li LU
Author Information
1. Ministry of Education Key Laboratory of Environmental Remediation and Ecosystem Health, Zhejiang University, Hangzhou, China. litq76@163.com
- Publication Type:Journal Article
- MeSH:
Adsorption;
Biodegradation, Environmental;
Cells, Cultured;
Kinetics;
Metabolic Clearance Rate;
Plant Roots;
cytology;
metabolism;
Sedum;
cytology;
metabolism;
Zinc;
pharmacokinetics
- From:
Journal of Zhejiang University. Science. B
2007;8(2):111-115
- CountryChina
- Language:English
-
Abstract:
Radiotracer techniques were employed to characterize (65)Zn adsorption and desorption in root-cell-wall of hyperaccumulating ecotype (HE) and non-hyperaccumulating ecotype (NHE) species of Sedum alfredii Hance. The results indicated that at the end of a 30 min short time radioisotope loading period, comparable amounts of (65)Zn were accumulated in the roots of the two ecotypes Sedum alfredii, whereas 2.1-fold more (65)Zn remains in NHE root after 45-min desorption. At the end of 60 min uptake period, no difference of (65)Zn accumulation was observed in undesorbed root-cell-wall of Sedum alfredii. However, 3.0-fold more (65)Zn accumulated in desorbed root-cell-wall of NHE. Zn(2+) binding in root-cell-wall preparations of NHE was greater than that in HE under high Zn(2+) concentration. All these results suggested that root-cell-wall of the two ecotypes Sedum alfredii had the same ability to adsorb Zn(2+), whereas the desorption characteristics were different, and with most of (65)Zn binding on root of HE being available for loading into the xylem, as a result, more (65)Zn was translocated to the shoot.
