Gray mold (Botrytis fruit rot)—Botrytis cinerea
Flattened black masses of sclerotia appear on the canes
of Botrytis-infested caneberry plants in late winter. In
spring, sclerotia germinate to form masses of spores. Opened
flowers may become infected, and the fungus will sporulate
on the blighted flowers. Infected berries left on the vine
become mummified. In storage, white mycelia can cover infected
berries.
Life cycle
Solutions
To promote air circulation and quicken drying of plant tissue,
allow berries to ripen in an open canopy. Open canopies can
be created by heavy pruning to maintain a narrow row of plantings,
removing the first flush of primocanes, minimizing nitrogen
fertilizer applic ation, and controlling weeds. Training
systems also help. Some red raspberry
cultivars are partially resistant. Pick fruit during cool
temperatures and refrigerate promptly. Remove fruit mummies
and dead leaves before tying up fruit canes in the fall. | 
Botrytis spores covering fruit
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