INTERACTIONS BETWEEN SAPROTROPHIC FUSARIUM STRAINS AND ARBUSCULAR MYCORRHIZAS OF SOYBEAN PLANTS

We studied the effect of inoculation with the saprotrophic fungi Fusar ium concolor-2183, F, equiseti-91, F. graminearum-122, F. lateritium-2 317, F, moniliforme-379, F, oxysporum-93, F. oxysporum-738, F. oxyspor um-126, F, solani-51, F. solani-339, F, solani-2584 and F. stilboide-2 169 on soybean (Glycine max) in unsterile and sterilized soils and in soils with or without arbuscular mycorrhizal (AM) inoculation with Glo mus mosseae, in a greenhouse trial. Plant dry weight of non AM soybean was unaffected by the presence of any Fusarium. In contrast, AM colon ization increased under all experimental conditions when F. oxysporum- 738, F. oxysporum-126 or F. stilboide-2169 was used, and AM plant shoo t dry weight increased in the presence of F, oxysporum-93, F, oxysporu m-738, F, oxysporum-126 or F. solani-51. Synergistic effect of some Fu sarium strains on G. mosseae but not effect of the AM fungus on the sa protrophic fungi were found.