Abstract
Phosphorus is one of the most important limiting nutrients in Brazilian grasslands. Therefore, the function of soil microorganisms, especially arbuscular mycorrhizal fungi (AM fungi), has been attracted considerable attention, because AM fungi can absorb phosphorus from soil and supply it to host plants. To clarify their function in the Agropastoral system, the AM fungi in some fields in the Agropastoral system experiment in Brazil was investigated. The colonization of AM fungi was higher in soybean roots in the Continuous Crop field than in grass roots in Continuous Pasture and Degraded Pasture. Spore density was higher in the Continuous Crop field, where soybean was cultivated, than in the Pastures. Especially, Gigaspora sp. was abundantly found in the Continuous Crop field. These results suggest that even if the fields are close to each other, the dynamics of AM fungi is different probably due to different host plant species and fertilizer conditions.
