ABSTRACT

Overexploitation of forest resources resulting from excessive industrial exploitation, clearing for industrial purposes, and collection of fi rewood has led to a dramatic deforestation during recent decades in the Mediterranean and tropical areas (Piéri 1991). One of the detrimental effects of deforestation is soil degradation and desertifi cation processes resulting in alterations of

1UMR 113 CIRAD/INRA/IRD/SUP-AGRO/UM2, Laboratoire des Symbioses Tropicales et Méditerranéennes (LSTM). TA A-82/J, Campus International de Baillarguet. Montpellier Cedex 5, France. 2Laboratoire Commun de Microbiologie (LCM) IRD/UCAD/ISRA, Centre de Recherche de Bel Air, BP. 1386, CP. 18524 Dakar, Sénégal. *Corresponding author: Robin.Duponnois@ird.fr

major physicochemical and biological soil properties (Requena et al. 2001). The disturbances in plant cover largely contribute to increase soil erosion and decrease soil fertility and microbial activities (Garcia et al. 1997). Numerous studies have reported that in such conditions, indigenous inoculum levels of mycorrhizal fungi were signifi cantly altered (Duponnois et al. 2001, Azcon-Aguilar et al. 2003). The mycorrhizal symbiotic establishment takes up and transports nutrients to plant roots, improves soil aggregation in eroded soils, and reduces water stress (Smith and Read 2008).