THE OCCURRENCE OF ANTAGONISTIC BACTERIA IN GLOMUS-MOSSEAE POT CULTURES

Biological control of root diseases, carried out by the manipulation o f resident microbes or by the introduction of antagonists, should take into account the role played by mycorrhizal fungi in the mycorrhizosp here. In this work we have detected many antagonistic bacteria within the different zones of the mycorrhizosphere of the arbuscular mycorrhi zal (AM) fungus Glomus mosseae, grown for 17 years in pot cultures. Th e selected bacteria were actively antagonistic against in vitro myceli al growth of species of the soil-borne pathogens Fusarium and Phytopht hora and on the germination and germ tube growth of Phytophthora paras itica zoospores. These results are evidence of the mycorrhizal compati bility of the antagonistic bacteria isolated from the mycorrhizosphere and suggest the possibility of using AM fungi as vehicles of selected microorganisms in biological control of soil-borne pathogens.