DUAL AXENIC CULTURE OF SHEARED-ROOT INOCULA OF VESICULAR-ARBUSCULAR MYCORRHIZAL FUNGI ASSOCIATED WITH TOMATO ROOTS

Surface-sterilized sheared-root inocula of two vesicular-arbuscular my corrhizal (VAM) fungi (Glomus intraradices and G. versiforme) from pot cultures associated with excised tomato roots showed significant spor ulation and the production of an extensive hyphal biomass. As many as 10(2)-10(3) axenic mature spores were recovered in Petri dishes during 3 months incubation in the dark. Propagules of both species were able to complete their vegetative life cycle in vitro and efficiently colo nize Acacia albida roots after 1 month under greenhouse conditions. Th e effectiveness of 0.5-cm pieces of VAM roots as starter inocula indic ates the high inoculum potential of intravesicle propagules.