Abstract
A new disease of aster was found in Yamanashi Prefecture, Japan, 1989. Dark brown or tan-colored spots with dark margin appeared on the leaves, stems and flower buds of the host. A species of Stemphylium isolated from the lesions was pathogenic to asparagus, tomato, soybean, stone leek and onion as well as aster. The pathogen was identified as S. vesicarium from its conidial morphology and host range. The fungus is new in Japan and aster is new host for it.
