ABSTRACT
In the ecosystem concept, agroecosystems are characterized by major dependence on and influence by factors external to the system such as energy and agricultural chemicals and their residues. The soil module of agroecosystems is a prime arena for enhancement of internal control mechanisms because it is a biologically dynamic, rather than static resource. Management of agroecosystems often involves inputs which have a negative impact on mycorrhizosystem function. At global and agroecosystem scales, the interactions of soil parent material, water, and air have led to large areas where soil moisture, texture, fertility and the micro- and macro-fauna associated with the fertility status, are favorable for establishment of Vesicular-arbuscular mycorrhizal (VAM) symbiosis. AM fungi and VAM fungal biomass are integral parts of soil-plant productivity because of their roles in: amelioration of environmentally induced plant stress; soil structure development; and carbon, nitrogen, and phosphorus cycling.
