A Guide to Grapevine Abnormalities in South Africa - P.G. GOUSSARD

Downy mildew.

PHOTO 38. Infection of young, green shoots with downy mildew results in the shoots’ blackening, whereafter they turn brown, burst and dry out.

PHOTO 39. Young vines can be wiped out entirely following downy mildew infection of young, green shoots.

PHOTO 40. A typical example of flower clusters being wiped out as a result of downy mildew infection.

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