endomycorrhiza: (pl. endomycorrhizae; syn. vesicular-arbuscular mycorrhiza)
symbiotic association between a nonpathogenic or weakly pathogenic fungus and the roots of plants in which fungal hyphae invade cortical cells of the root (see ectomycorrhiza)
(vesicles of an endomycorrhizal fungus in alfalfa root stained with trypan blue)