Combinations of different arbuscular mycorrhizal fungi improve fitness and metal tolerance of sorghum in ultramafic soil

International audienceResearch on arbuscular mycorrhizal fungi (AMF) in ultramafic soils has principally focused on ecological restorationwhereas little attention has been given to agriculture. The present study aims at understanding ifmixtures of different AMF species from a New Caledonian ultramafic soil induced a better plant fitness and lowercontents of potentially toxic metals in aerial parts of a crop plant than single species inoculants. Sorghum vulgareplants were inoculated using six AMF species separately and in different mixtures of these species in a glasshouseexperiment in ultramafic soil. The tested inocula showed very different effects on plant fitness. Results highlightthat, when sorghum is grown in ultramafic soil, AMF mixes were more efficient than single species inoculation inalleviating abiotic stresses by reducing translocation of potentially toxic metals to the aerial part of the plant andthereby improving the fitness of the plants. Our findings point out the utility of arbuscular mycorrhizal biotechnologyfor agricultural ultramafic soils