The fungus is seen most often as a root and lower stem pathogen. Fusarium has a wide host range. It may act alone or more often is association with other soilborne pathogenic fungi, such as Rhizoctonia or Pythium . Necrosis of roots often beginning with lateral roots. A red-pinkish discoloration is often associated with infected tissue.
Infection generally moves upward through the plant.
Conidiophores may be single or branched with conidia produced at the tips. Macroconidia can vary greatly in size and shape. Microconidia are colorless, small, oval to short cylindrical and one or two-celled. Chlamydospores are thick walled, rounded cells typically found in older mycelium. They are fungal survival structures.