title: Nickel tolerance of serpentine and non-serpentine Knautia arvensis plants as affected by arbuscular mycorrhizal symbiosis.
abstract: Serpentine soils have naturally elevated concentrations of certain heavy metals, including nickel. This study addressed the role of plant origin (serpentine vs. non-serpentine) and symbiosis with arbuscular mycorrhizal fungi (AMF) in plant Ni tolerance. A semi-hydroponic experiment involving three levels of Ni and serpentine and non-serpentine AMF isolates and populations of a model plant species (Knautia arvensis) revealed considerable negative effects of elevated Ni availability on both plant and fungal performance. Plant growth response to Ni was independent of edaphic origin; however, higher Ni tolerance of serpentine plants was indicated by a smaller decline in the concentrations of photosynthetic pigments and restricted root-to-shoot Ni translocation. Serpentine plants also retained relatively more Mg in their roots, resulting in a higher shoot Ca/Mg ratio. AMF inoculation, especially with the non-serpentine isolate, further aggravated Ni toxicity to host plants. Therefore, AMF do not appear to be involved in Ni tolerance of serpentine K. arvensis plants.
authors.affiliation: Institute of Botany, Academy of Sciences of the Czech Republic, 252 43, Průhonice, Czech Republic, dbp@centrum.cz.
authors.forename: Pavla
authors.initials: P
authors.lastname: Doubková
authors.forename: Radka
authors.initials: R
authors.lastname: Sudová
mesh_terms: D049917:Dipsacaceae / Q000187:drug effects* / Q000382:microbiology* / Q000502:physiology; D005658:Fungi / Q000502:physiology*; D038821:Mycorrhizae / Q000502:physiology*; D009532:Nickel / Q000494:pharmacology*; D010944:Plants / Q000187:drug effects* / Q000382:microbiology / Q000469:parasitology; D013559:Symbiosis
chemical_list: D009532:Nickel