the present book entitled "variation in occurrence of Arbuscular Mycorrhizal fungi" clearly indicated the existence of variation in their occurrence, association and diversity in Arbuscular mycorrhizal fungi species with respect to different group of crops viz., cereals, pulses, spices and vegetables studied during kharif and rabi season.AM symbiosis is the oldest, most important and ubiquitously associated with the large majority of plant families in different ecosystem across the world, ranging from the tropic or arctic alpine habitats to masic and arid habits.AM fungi benefit their host principally by increasing uptake of relatively immobile phosphate ion, nutrients such as zinc, phosphorus and copper. Its transport and absorption can also increase biomass production in soil with low potassium, calcium and magnesium.Other benefit to the host that have been identified include: improved drought resistance, increased tolerance to salinity and heavy metals, increased resistance to soil pathogens and folior feeding insects