Histopathological features of onion tissues infected with Fusarium equiseti showed infection progress from the roots where the pathogen move through the vascular system to colonize the whole plant. At first, in the intercellular spaces of the root cortex but soon invaded the cells, followed by colonization of the cells by its hyphae and microconidia. At later stages, the cortex tissue became completely disorganized and decomposed as the pathogen advanced to the shoot system via the vessel elements.