ABSTRACT
It is now very well documented that arbuscular mycorrhizal fungi (AMF) improve fitness and growth of plants that are important in agriculture, horticulture and forestry. The soil hyphal network produced by AMF during association with the plant host provides a greater absorptive surface than root hairs alone and thus increases significantly the absorption of relatively immobile ions such as phosphate, copper and zinc. In most tropical soils, available phosphorus is very low and thereby limiting for plant development. In addition, mycorrhizally infected plants have been shown to have greater tolerance to toxic metals, to root pathogens, to drought, to high soil temperature, to saline soils, to adverse soil pH and to transplant shock than non-mycorrhizal plants (Mosse et al, 1981; Bagyaraj, 1990; Bagyaraj and Varma, 1995). AMF have been reported from natural ecosystems such as deserts, sand dunes, tropical forests, salt marshes and managed systems such as pastures, orchards and field crops (Brundrett, 1991).
