ULTRASTRUCTURAL STUDIES ON SPORES OF GLOMUS INTRARADICES

Studies were conducted to determine the morphology and ultrastructure of spores of Glomus intraradices, a species of arbuscular mycorrhizal fungus that usually produces its spores inside the host root. Differen t wall structures are observed and wall development is described with both light microscopy and TEM. In mature spores the wall is formed by two zones: an outer, disintegrating zone and an inner zone with severa l layers. Mature spores have large centrally located lipid droplets an d a peripheral layer of cytoplasm containing numerous nuclei, mitochon dria, polyphosphate granules, and small lipid droplets.