Vesicular-Arbuscular Mycorrhizae as Modifiers of Soil Fertility

Abstract

It has become clear that microbial activity must be considered a key component among those conferring “soil fertility,” i.e., the ability of a given soil to support plant development and nutrition (Pauli, 1967). The major components interacting to determine “soil fertility” are depicted in Figure 1. Accordingly, “fertility” can be considered an inherent property of a given soil. However, the plant itself is able to modify soil fertility in two different ways. One is based on the “rhizosphere effect” exerted by the plant, which can alter the fluxes of energy and the supply of substrates for soil microorganisms. The other way is based on the inherently different growth rates and metabolism of the different plant species that are known to “change” the capacity of the soil to provide each particular plant with nutrients (Hayman, 1975).