Philippe Jourand1, Laure Hannibal2, Clarisse Majorel2, Stéphane Mengant3, Marc Ducousso4, Michel Lebrun5. 1. IRD, UR040 LSTM, TA A-82/J Campus International de Baillarguet, 34398 Montpellier Cedex 5, France. Electronic address: philippe.jourand@ird.fr. 2. IRD, UR040 LSTM, TA A-82/J Campus International de Baillarguet, 34398 Montpellier Cedex 5, France. 3. Université de Nouvelle-Calédonie, Laboratoire insulaire du vivant et de l'environnement, B.P. R4, 98851 Nouméa Cedex, New Caledonia. 4. CIRAD, UR 82 LSTM, TA A-82/J Campus International de Baillarguet, 34398 Montpellier Cedex 5 France. 5. Université Montpellier 2, UMR28 LSTM, TA A-82/J Campus International de Baillarguet, 34398 Montpellier Cedex 5, France.
Abstract
Ectomycorrhizal fungi (ECM) isolates of Pisolithus albus (Cooke and Massee) from nickel-rich ultramafic topsoils in New Caledonia were inoculated onto Acacia spirorbis Labill. (an endemic Fabaceae) and Eucalyptus globulus Labill. (used as a Myrtaceae plant host model). The aim of the study was to analyze the growth of symbiotic ECM plants growing on the ultramafic substrate that is characterized by high and toxic metal concentrations i.e. Co, Cr, Fe, Mn and Ni, deficient concentrations of plant essential nutrients such as N, P, K, and that presents an unbalanced Ca/Mg ratio (1/19). ECM inoculation was successful with a plant level of root mycorrhization up to 6.7%. ECM symbiosis enhanced plant growth as indicated by significant increases in shoot and root biomass. Presence of ECM enhanced uptake of major elements that are deficient in ultramafic substrates; in particular P, K and Ca. On the contrary, the ECM symbioses strongly reduced transfer to plants of element in excess in soils; in particular all metals. ECM-inoculated plants released metal complexing molecules as free thiols and oxalic acid mostly at lower concentrations than in controls. Data showed that ECM symbiosis helped plant growth by supplying uptake of deficient elements while acting as a protective barrier to toxic metals, in particular for plants growing on ultramafic substrate with extreme soil conditions. Isolation of indigenous and stress-adapted beneficial ECM fungi could serve as a potential tool for inoculation of ECM endemic plants for the successful restoration of ultramafic ecosystems degraded by mining activities.
Ectomycorrhizal fungi (ECM) isolates of n>an class="Species">Pisolithus albus (Cooke and Massee) from nickel-rich ultramafic topsoils in New Caledonia were inoculated onto Acacia spirorbis Labill. (an endemic Fabaceae) and Eucalyptus globulus Labill. (used as a Myrtaceae plant host model). The aim of the study was to analyze the growth of symbiotic ECM plants growing on the ultramafic substrate that is characterized by high and toxic metalconcentrations i.e. Co, Cr, Fe, Mn and Ni, deficient concentrations of plant essential nutrients such as N, P, K, and that presents an unbalanced Ca/Mg ratio (1/19). ECM inoculation was successful with a plant level of root mycorrhization up to 6.7%. ECM symbiosis enhanced plant growth as indicated by significant increases in shoot and root biomass. Presence of ECM enhanced uptake of major elements that are deficient in ultramafic substrates; in particular P, K and Ca. On the contrary, the ECM symbioses strongly reduced transfer to plants of element in excess in soils; in particular all metals. ECM-inoculated plants released metalcomplexing molecules as free thiols and oxalic acid mostly at lower concentrations than in controls. Data showed that ECM symbiosis helped plant growth by supplying uptake of deficient elements while acting as a protective barrier to toxic metals, in particular for plants growing on ultramafic substrate with extreme soil conditions. Isolation of indigenous and stress-adapted beneficial ECM fungi could serve as a potential tool for inoculation of ECM endemic plants for the successful restoration of ultramafic ecosystems degraded by mining activities.
Authors: Gabriela C Canton; Amanda A Bertolazi; Antônio J D Cogo; Frederico Jacob Eutrópio; Juliana Melo; Sávio Bastos de Souza; Cesar A Krohling; Eliemar Campostrini; Ary Gomes da Silva; Arnoldo R Façanha; Nuno Sepúlveda; Cristina Cruz; Alessandro C Ramos Journal: Mycorrhiza Date: 2016-02-10 Impact factor: 3.387
Authors: Guillaume Losfeld; Laurent L'Huillier; Bruno Fogliani; Tanguy Jaffré; Claude Grison Journal: Environ Sci Pollut Res Int Date: 2014-07-29 Impact factor: 4.223