From March/1988 to July/1990, in 14 opportunities, it was collected 410 soil samples of rhizospheres of native plants from sandy soils of Ilha do Cardoso, SP, Brazil to investigate the occurrence of AM fungi. The studied plants were: Baccharis trimera DC., Blutaparon portulacoides (St. Hil.) Mears, Dalbergia hecastaphylla (L.) Taub., Hydrocotyle bonariensis Lam., Ipomoea pes-caprae (L.) Swett and Polygala cyparisseas St. Hil. It was observed 24 species of AM fungi. The results showed: a) a tendency to increase the number of spores in the soil with the increase of the temperature, rainfall and sunlight; b) different species of AM fungi occurred in different species of hosts, suggesting ecological specificity of AM fungi; c) it was observed higher abundance of spores of Acaulospora, Gigaspora and Scutellospora over spores of Glomus and Sclerocystis. It was not observed relatonships between the number of spores in the soil, taxa of colonization of the roots and the fenology of hosts plants.
AM fungi; sandy soil; ecology