title: Arbuscular mycorrhizal symbiosis influences arsenic accumulation and speciation in Medicago truncatula L. in arsenic-contaminated soil.
abstract: In two pot experiments, wild type and a non-mycorrhizal mutant (TR25:3-1) of Medicago truncatula were grown in arsenic (As)-contaminated soil to investigate the influences of arbuscular mycorrhizal fungi (AMF) on As accumulation and speciation in host plants. The results indicated that the plant biomass of M. truncatula was dramatically increased by AM symbiosis. Mycorrhizal colonization significantly increased phosphorus concentrations and decreased As concentrations in plants. Moreover, mycorrhizal colonization generally increased the percentage of arsenite in total As both in shoots and roots, while dimethylarsenic acid (DMA) was only detected in shoots of mycorrhizal plants. The results suggested that AMF are most likely to get involved in the methylating of inorganic As into less toxic organic DMA and also in the reduction of arsenate to arsenite. The study allowed a deeper insight into the As detoxification mechanisms in AM associations. By using the mutant M. truncatula, we demonstrated the importance of AMF in plant As tolerance under natural conditions.
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Bai-Hui
authors.initials: BH
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Song-Lin
authors.initials: SL
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Yu-Qing
authors.initials: YQ
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Ge
authors.initials: G
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: bdchen@rcees.ac.cn.
authors.forename: Bao-Dong
authors.initials: BD
authors.lastname: Chen
mesh_terms: D001151:Arsenic / Q000032:analysis / Q000378:metabolism* / Q000493:pharmacokinetics*; D018053:Arsenites / Q000378:metabolism; D018533:Biomass; D046913:Medicago truncatula / Q000378:metabolism*; D038821:Mycorrhizae / Q000502:physiology*; D010084:Oxidation-Reduction; D010758:Phosphorus / Q000032:analysis; D018517:Plant Roots / Q000737:chemistry; D018520:Plant Shoots / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000494:pharmacology*; D013559:Symbiosis
chemical_list: D018053:Arsenites; D012987:Soil; D012989:Soil Pollutants; D010758:Phosphorus; C015001:arsenite; D001151:Arsenic
keywords: Arbuscular mycorrhizal fungi; Arsenic speciation; Medicago truncatula; Mutant; Phosphorus