Black Rot of Grapes
Guignardia bidwellii
Grapefungal
A destructive fungal disease that shrivels berries into hard black "mummies".
Symptoms
Small tan leaf spots with dark borders, and berries that shrivel into hard, black "mummies".
Favorable conditions
- •Warm, wet weather from bud break through veraison
- •Overwintering mummified berries and infected canes
Management
- 1Apply a fungicide program from bud break through veraison
- 2Remove mummified berries and infected canes
- 3Improve canopy airflow
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