title: Spatial imaging and speciation of Cu in rice (Oryza sativa L.) roots using synchrotron-based X-ray microfluorescence and X-ray absorption spectroscopy.
abstract: Knowledge of elemental localization and speciation in rice (Oryza sativa L.) roots is crucial for elucidating the mechanisms of Cu accumulation so as to facilitate the development of strategies to inhibit Cu accumulation in rice grain grown in contaminated soils. Using synchrotron-based X-ray microfluorescence and X-ray absorption spectroscopy, we investigated the distribution patterns and speciation of Cu in rice roots treated with 50 μM Cu for 7 days. A clear preferential localization of Cu in the meristematic zone was observed in root tips as compared with the elongation zone. Investigation of Cu in the root cross sections revealed that the intensity of Cu in the vascular bundles was more than 10-fold higher than that in the other scanned sites (epidermis and cortex) in rice roots. The dominant chemical form of Cu (79.1%) in rice roots was similar to that in the Cu-cell wall compounds. These results suggest that although Cu can be easily transported into the vascular tissues in rice roots, most of the metal absorbed by plants is retained in the roots owing to its high binding to the cell wall compounds, thus preventing metal translocation to the aerial parts of the plants.
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China.
authors.forename: Lingli
authors.initials: L
authors.lastname: Lu
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China.
authors.forename: Ruohan
authors.initials: R
authors.lastname: Xie
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Liu
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China.
authors.forename: Haixing
authors.initials: H
authors.lastname: Wang
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China.
authors.forename: Dandi
authors.initials: D
authors.lastname: Hou
authors.affiliation: Institute of Chemical & Engineering Sciences, Agency for Science, Technology and Research (ASTAR), Jurong Island, Singapore 627833, Singapore.
authors.forename: Yonghua
authors.initials: Y
authors.lastname: Du
authors.affiliation: University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Fort Pierce, FL 34945, USA.
authors.forename: Zhenli
authors.initials: Z
authors.lastname: He
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China; University of Florida, Institute of Food and Agricultural Sciences, Indian River Research and Education Center, Fort Pierce, FL 34945, USA.
authors.forename: Xiaoe
authors.initials: X
authors.lastname: Yang
authors.affiliation: Ningbo Agriculture Bureau, Ningbo 315012, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Sun
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China. Electronic address: tiansk@zju.edu.cn.
authors.forename: Shengke
authors.initials: S
authors.lastname: Tian
mesh_terms: D001692:Biological Transport; D003300:Copper / Q000032:analysis* / Q000378:metabolism; D018519:Meristem / Q000737:chemistry / Q000378:metabolism; D008962:Models, Theoretical; D012275:Oryza / Q000737:chemistry* / Q000378:metabolism; D018517:Plant Roots / Q000737:chemistry* / Q000378:metabolism; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism; D013052:Spectrometry, X-Ray Emission; D017356:Synchrotrons; D056928:X-Ray Absorption Spectroscopy
chemical_list: D012989:Soil Pollutants; D003300:Copper
keywords: Copper; Localization; Rice; Root; Speciation