Rust
Crop: Onion Disease: Fungal Pathogen: Puccinia allii (synonym: P. porri)
SYMPTOMS AND SIGNS
DISEASE DEVELOPMENT
DISEASE MANAGEMENT
- Rust brown clusters of spores (pustules) forms all over the leaf. The leaf tissue surrounding the pustules turns a pale yellow. Later on in the season dark brown spores can form.
- The disease first appears as small, circular, white to tan lesions along leaf veins. Lesions develop into orange to red circular or elongate uredial pustules that are often surrounded by chlorosis.
- The leaf tissue surrounding the pustules turns a pale yellow. Later on in the season dark brown spores can form. When disease pressure is severe, leaves turn yellow and die prematurely.
- Small, circular, white to tan lesions appears along leaf veins. Lesions develop into orange to red circular or elongate uredial pustules that are often surrounded by chlorosis.
- When disease pressure is severe, leaves turn yellow and die prematurely. Dark brown teliospores may form in the pustules later in the season.
- Dark brown fungal teliospores( final stage in the life cycle of a rust fungus) forming in the pustules later in the season.