title: Arbuscular mycorrhizal fungi enhance both absorption and stabilization of Cd by Alfred stonecrop (Sedum alfredii Hance) and perennial ryegrass (Lolium perenne L.) in a Cd-contaminated acidic soil.
abstract: A greenhouse pot experiment was conducted to compare the phytoextraction efficiencies of Cd by hyper-accumulating Alfred stonecrop (Sedum alfredii Hance) and fast-growing perennial ryegrass (Lolium perenne L.) from a Cd-contaminated (1.6 mg kg(-1)) acidic soil, and their responses to the inoculations of two arbuscular mycorrhizal (AM) fungal strains, Glomus caledonium 90036 (Gc) and Glomus mosseae M47V (Gm). Ryegrass and stonecrop were harvested after growing for 9 and 27 wk, respectively. Without AM fungal inoculation, the weekly Cd extraction by stonecrop (8.0 μg pot(-1)) was 4.3 times higher than that by ryegrass (1.5 μg pot(-1)). Both Gc and Gm significantly increased (P < 0.05) root mycorrhizal colonization rates, soil acid phosphatase activities, and available P concentrations, and thereby plant P absorptions (except for Gm-inoculated ryegrass), shoot biomasses, and Cd absorptions (except for Gm-inoculated stonecrop), while only Gc-inoculated stonecrop significantly accelerated (P < 0.05) the phytoextraction efficiency of Cd by 78%. In addition, both Gc and Gm significantly decreased (P < 0.05) phytoavailable Cd concentrations by 21-38% via elevating soil pH. The results suggested the potential application of hyper-accumulating Alfred stonecrop associated with AM fungi (notably Gc) for both extraction and stabilization of Cd in the in situ treatment of Cd-contaminated acidic soil.
authors.affiliation: Croucher Institute for Environmental Sciences and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, PR China; State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing 210008, PR China; Joint Open Laboratory of Soil and the Environment, Hong Kong Baptist University & Institute of Soil Science, Chinese Academy of Sciences, PR China. Electronic address: jlhu@issas.ac.cn.
authors.forename: Junli
authors.initials: J
authors.lastname: Hu
authors.forename: Shengchun
authors.initials: S
authors.lastname: Wu
authors.forename: Fuyong
authors.initials: F
authors.lastname: Wu
authors.forename: Ho Man
authors.initials: HM
authors.lastname: Leung
authors.forename: Xiangui
authors.initials: X
authors.lastname: Lin
authors.forename: Ming Hung
authors.initials: MH
authors.lastname: Wong
mesh_terms: D000042:Absorption; D001673:Biodegradation, Environmental; D002104:Cadmium / Q000378:metabolism*; D055137:Glomeromycota / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D008129:Lolium / Q000382:microbiology* / Q000502:physiology; D038821:Mycorrhizae / Q000502:physiology*; D018517:Plant Roots / Q000382:microbiology; D031963:Sedum / Q000382:microbiology* / Q000502:physiology; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium
keywords: DTPA-extractable Cd; Glomus caledonium; Glomus mosseae; Hyperaccumulator; Phytoremediation; Soil acid phosphatase