title: The role of metal nanoparticles in influencing arbuscular mycorrhizal fungi effects on plant growth.
abstract: A knowledge gap still remains concerning the in situ influences of nanoparticles on plant systems, partly due to the absence of soil microorganisms. Arbuscular mycorrhizal fungi (AMF) can form a mutualistic symbiosis with the roots of over 90% of land plants. This investigation sought to reveal the responses of mycorrhizal clover (Trifolium repens) to silver nanoparticles (AgNPs) and iron oxide nanoparticles (FeONPs) along a concentration gradient of each. FeONPs at 3.2 mg/kg significantly reduced mycorrhizal clover biomass by 34% by significantly reducing the glomalin content and root nutrient acquisition of AMF. In contrast, no negative effects of AgNPs at concentrations over 0.1 mg/kg were observed; however, AgNPs at 0.01 mg/kg inhibited mycorrhizal clover growth. In response to the elevated AgNPs content, the ability of AMF to alleviate AgNPs stress (via increased growth and ecological behaviors) was enhanced, which decreased Ag content and the activities of antioxidant enzymes in plants. These results were further supported by X-ray microcomputed tomography. Our findings suggest that in soil ecosystem, the influence of nanometals on plant systems would be more complicated than expected, and more attention should be focused on plant responses in combination with those of soil microorganisms.
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, PR China.
authors.forename: Youzhi
authors.initials: Y
authors.lastname: Feng
authors.forename: Xiangchao
authors.initials: X
authors.lastname: Cui
authors.forename: Shiying
authors.initials: S
authors.lastname: He
authors.forename: Ge
authors.initials: G
authors.lastname: Dong
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Junhua
authors.initials: J
authors.lastname: Wang
authors.forename: Xiangui
authors.initials: X
authors.lastname: Lin
mesh_terms: D018533:Biomass; D005290:Ferric Compounds / Q000633:toxicity; D005656:Fungal Proteins / Q000737:chemistry; D006023:Glycoproteins / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D038821:Mycorrhizae / Q000187:drug effects*; D012834:Silver / Q000633:toxicity; D013312:Stress, Physiological; D013559:Symbiosis / Q000187:drug effects*; D029921:Trifolium / Q000187:drug effects* / Q000254:growth & development
chemical_list: D005290:Ferric Compounds; D005656:Fungal Proteins; D006023:Glycoproteins; C573268:glomalin; C000499:ferric oxide; D012834:Silver