Expert Problem Solver

Anthracnose Spot

(Black Spot)

Anthracnose Spot
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Bonide Solutions:
 
Black Spot fungus or anthracnose, is a serious disease of grapevines. Grapes appear as small, black dots. Purple to black, sunken lesions may also appear on young shoots and stems. Symptoms on fruit appear when the grapes are half grown. First, small brownish spots appear on fruit. These spots enlarge very quickly, rotting the entire berry within a few days. The infected fruit shrivels, becomes hard, black, and wrinkled. These shriveled, infected fruits are called mummies. Black spot can also attack all green parts of the vine.
Cool wet weather during spring and early summer particularly favors outbreaks of the disease, as surface moisture is essential for the spread of fungal spores and infection.
Timing of key early season sprays for control of back spot should be as follows starting at 50% budburst continuing 3-weeks after bud-burst.
Use preventive control before signs of disease starts.