Onions - Stemphyllium Blight
Stemphyllium Blight
(fungus - Stemphyllium vesicarium): Lesions are initially light yellow to
brown and water-soaked. They elongate, often reaching the leaf tips, and
become dark brown to black. The disease can become serious following periods
of more than 24 hours of rainy weather. Fungicides used to control purple
blotch will also control this disease.