title: Rhizosphere bacteria enhance the accumulation of selenium and mercury in wetland plants.
abstract: The role of rhizosphere bacteria in facilitating Se and Hg accumulation in two wetland plants, saltmarsh bulrush (Scirpus robustus Pursh) and rabbitfoot grass (Polypogon monspeliensis (L.) Desf.), was studied. Ampicillin-amended plants (i.e., with inhibited rhizosphere bacteria) supplied with Na(2)SeO(4) or HgCl(2) had significantly lower concentrations of Se and Hg, respectively, in roots than plants without ampicillin. These results were confirmed by inoculating axenic saltmarsh bulrush plants with bacteria isolated from the rhizosphere of plants collected from the field; these plants accumulated significantly more Se and Hg compared to axenic controls. Therefore, rhizosphere bacteria can increase the efficiency of Se and Hg phytoremediation by promoting the accumulation of Se and Hg in tissues of wetland plants.
authors.affiliation: University of California, Berkeley, Department of Plant and Microbial Biology, 111 Koshland Hall, Berkeley, CA 94720-310, 2, USA
authors.lastname: de Souza MP
authors.initials: CP
authors.lastname: Huang
authors.initials: N
authors.lastname: Chee
authors.initials: N
authors.lastname: Terry