Ectomycorrhization of Acacia mangium, Willd. and Acacia holosericea, A.!Cunn ex G.!Don in Senegal.: Impact on plant growth, populations of indigenous symbiotic microorganisms and plant parasitic nematodes

The ectomycorrhization of two Australian Acacia species (A. mangium and A. holoscricea) with two basidiomycetes (Pisolithus and Scleroderma) was studied in sterilized and unsterilized soils. The three fungal isolates, two exotic strains (Pisolithus COI 007 and COI 024) and one indigenous (Sclerodermal) enhanced the development of the Acacia species. In the unsterilized soil, the number of nodules per plant of indigenous rhizobia was increased when the plants had associated mycorrhizae. The plant parasitic nematode community was reduced by the fungal strains, especially for H. pararobustus with A. holosericea. The ectomycorrhizal associations of the Australian Acacias, mostly unknown in West Africa, appears to be very promising for use of these trees in afforestation programs. (C) 2002 Elsevier Science Ltd.