Stemphylium blight: Black fruiting bodies on leaves
Pathogen: Stemphylium vesicarium Symptoms Initially small, light yellow to brown, watery spots appears on the affected leaves which later...
Stemphylium blight: Affected onion plants in field
Pathogen: Stemphylium vesicarium Symptoms Initial infections on the leaves and leaf sheaths are small, light yellow to brown, and...
Stemphylium blight: Leaves dry at the edges with dark spots
Pathogen: Stemphylium vesicarium Symptoms Dark spots on the ends of dying stems can be seen. The leaves and leaf sheaths are small, light...
Stemphylium blight: Dark brown blotches on leaves
Pathogen: Stemphylium vesicarium Symptoms An attack begins with small, light yellow to brown, watery spots. After a while these develop...
Stemphylium blight: Lesions formation on leaves
Pathogen: Stemphylium vesicarium Symptoms Lesions are often more numerous on the sides of onion leaves facing the prevailing wind.The...
Stemphylium blight: A leaf miner scar
Pathogen: Stemphylium vesicarium Symptoms Since this fungus is usually found co-infecting with Alternaria porri, symptoms are identical...
Rust: Teliospores on onion leaf
Pathogen: Puccinia allii (synonym: P. porri) Symptoms Dark brown fungal teliospores( final stage in the life cycle of a rust fungus)...
Rust: Advance stage of infection
Pathogen: Puccinia allii (synonym: P. porri) Symptoms When disease pressure is severe, leaves turn yellow and die prematurely. Dark brown...
Rust Appearance of lesions on onion leaves
Pathogen: Puccinia allii (synonym: P. porri) Symptoms Small, circular, white to tan lesions appears along leaf veins. Lesions develop...
Rust: Yellowing of leaf tissue
Pathogen: Puccinia allii (synonym: P. porri) Symptoms The leaf tissue surrounding the pustules turns a pale yellow. Later on in the...