title: [Effect of ectomycorrhizae on heavy metals sequestration by thermostable protein in rhizosphere of Pinus tabulaeformis under Cu and Cd stress].
abstract: Copper and cadmium in soil is a severe soil pollution problem in China. It is effective to remediate the soil by sequestrating Cu and Cd with tolerant plant and microorganism. Ectomycorrhizae could exude a large number of organic matter to reduce the biological effectiveness of heavy metals. Therefore, under Cu or Cd stress, thermostable protein in rhizosphere exuded by roots of pine seedling (Pinus tabulaeformis) associated with ectomycorrhizal fungi (Xerocomus chrysenteron) can have the potential of sequestration for heavy metals. The results illustrated that the association didn't impact on exudation of thermostable protein but treated with different concentrations of Cu, the total thermostable protein (TTP) and easily extracted thermostable protein (EETP) in mycorrhizal rhizosphere increased by 2.64 to 11.79 times compared with non-mycorrhizal one. While treated with Cd, it was 1.49 to 7.56 times. Further analysis of metal content in rhizosphere showed that association significantly increased the Cu sequestration in mycorrhizal rhizosphere where relative content of Cu was 1.81 to 2.75 times higher than those in non-mycorrhizal rhizosphere while most of Cu was sequestrated by thermostable protein, 4.19 to 43.00 times higher in protein than in root cell. Meanwhile results of Cd treatments showed a similar trend with Cu treatments. That indicated that under excessive heavy metals stress, ectomycorrhizal association facilitated the exudation of thermostable protein so as to extend the capacity of sequestration for excessive heavy metals and mitigate the phytotoxicity from heavy metals polluted soil.
authors.forename: Ying-Wei
authors.initials: YW
authors.lastname: Zhang
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Chai
authors.forename: Dong-Wei
authors.initials: DW
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Huang
mesh_terms: D002104:Cadmium / Q000032:analysis; D002681:China; D003300:Copper / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis*; D038821:Mycorrhizae; D028223:Pinus / Q000378:metabolism / Q000382:microbiology*; D018517:Plant Roots / Q000378:metabolism / Q000382:microbiology; D058441:Rhizosphere; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D003300:Copper