Powdery mildew of cherry
Disease
Powdery mildew of cherry
Podosphaera clandestine (Wallr.:Fr.) Lév.
Distribution: Occurs all along the east coast.
Photos
Near the end of the season, small, black fungal bodies are visible.
Thomas Burr, Cornell Univ.
B
The fungus attacks young leaves and shoots and tends to cause more damage on sour cherry than sweet cherry. Infections appear as white circular lesions or patches of powdery growth on either side of the leaf or on the terminal ends of shoots (A). Severely infected leaves curl upward or blister but eventually drop as infection progresses. Towards the end of the season, small, black fungal bodies (cleistothecia) are visible within powdery mildew colonies (B). Infected fruit are deformed when infected young, or develop circular, slightly sunken lesions when infection occurs on mature fruit.