Zinc distribution and speciation in Arabidopsis halleri x Arabidopsis lyrata progenies presenting various zinc accumulation capacities.
The purpose of this study was to investigate the relationship between the chemical form and localization of zinc (Zn) in plant leaves and their Zn accumulation capacity. An interspecific cross between Arabidopsis halleri sp. halleri and Arabidopsis lyrata sp. petrea segregating for Zn accumulation was used. Zinc (Zn) speciation and Zn distribution in the leaves of the parent plants and of selected F(1) and F(2) progenies were investigated by spectroscopic and microscopic techniques and chemical analyses. A correlation was observed between the proportion of Zn being in octahedral coordination complexed to organic acids and free in solution (Zn-OAs + Zn(aq)) and Zn content in the leaves. This pool varied between 40% and 80% of total leaf Zn depending on the plant studied. Elemental mapping of the leaves revealed different Zn partitioning between the veins and the leaf tissue. The vein : tissue fluorescence ratio was negatively correlated with Zn accumulation. The higher proportion of Zn-OAs + Zn(aq) and the depletion of the veins in the stronger accumulators are attributed to a higher xylem unloading and vacuolar sequestration in the leaf cells. Elemental distributions in the trichomes were also investigated, and results support the role of carboxyl and/or hydroxyl groups as major Zn ligands in these cells.
Sarret
Géraldine
G
Environmental Geochemistry Group, LGIT, University J. Fourier and CNRS, BP 53, 38041 Grenoble Cedex 9, France.
Willems
Glenda
G
Laboratoire de Génétique et Evolution des Populations Végétales, UMR 8016, CNRS, Université Lille 1, F-59655 Villeneuve d'Ascq, France.
Isaure
Marie-Pierre
MP
Environmental Geochemistry Group, LGIT, University J. Fourier and CNRS, BP 53, 38041 Grenoble Cedex 9, France.
Marcus
Matthew A
MA
Advanced Light Source, Lawrence Berkeley Lab, 1 Cyclotron Road, Berkeley, CA 94720, USA.
Fakra
Sirine C
SC
Advanced Light Source, Lawrence Berkeley Lab, 1 Cyclotron Road, Berkeley, CA 94720, USA.
Frérot
Hélène
H
Laboratoire de Génétique et Evolution des Populations Végétales, UMR 8016, CNRS, Université Lille 1, F-59655 Villeneuve d'Ascq, France.
Pairis
Sébastien
S
Institut Néel CNRS-UJF, Dept Matière Condensée, Matériaux et Fonctions, Pôle Instrumentation, 25 av. des Martyrs, BP 166, F-38042 Grenoble Cedex 9, France.
Geoffroy
Nicolas
N
Environmental Geochemistry Group, LGIT, University J. Fourier and CNRS, BP 53, 38041 Grenoble Cedex 9, France.
Manceau
Alain
A
Environmental Geochemistry Group, LGIT, University J. Fourier and CNRS, BP 53, 38041 Grenoble Cedex 9, France.
Saumitou-Laprade
Pierre
P
Laboratoire de Génétique et Evolution des Populations Végétales, UMR 8016, CNRS, Université Lille 1, F-59655 Villeneuve d'Ascq, France.
D000143:Acids / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D006824:Hybridization, Genetic; D008855:Microscopy, Electron, Scanning; D010641:Phenotype; D018515:Plant Leaves / Q000378:metabolism; D013045:Species Specificity; D013052:Spectrometry, X-Ray Emission; D014018:Tissue Distribution; D015032:Zinc / Q000737:chemistry / Q000378:metabolism*
D000143:Acids; D015032:Zinc