Diseases

Fusarium Wilt of Onion

Allium cepa L.

Fusarium wilt of onion, or Fusarium basal rot, is a dangerous disease caused by the specialized fungus Fusarium oxysporum f. sp. cepae. The disease affects the crop both during the growing season in the field and during storage, leading to tissue decay and the death of the root system.

In the reference 111 varieties crop Onion, where this is mentioned in the description.

The primary causative agent of the disease is Fusarium oxysporum f. sp. cepae, although the pathogen complex may include other fungal species of the genus Fusarium, such as F. acuminatum, F. annulatum, and F. proliferatum. SIX effector genes play a significant role in the pathogenicity of the fungus, although a clear classification into races for this form of the pathogen is poorly developed in onion breeding, and preference is given to assessing the aggressiveness of strains.

Symptoms of infection in growing plants manifest as yellowing and wilting of leaves from the tips, growth retardation, and browning of the roots. A white or pink mycelium often forms on the basal plate of the bulb. During storage, the infection provokes tissue softening and the development of mycelium between the bulb scales.

In breeding practice, specific gene markers for resistance to onion Fusarium wilt are virtually absent. The resistance of cultivars and hybrids is determined primarily by the results of phytopathological tests and is assessed through disease severity indices or general HR and IR categories for the pathogen.

General information about the subject — on the page Fusarium wilt and blight.

Sources8

Varieties of Onion mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.