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

Downy mildew.

PHOTO 45. The first signs of shrivelling of slightly larger berries are visually perceptible while fungal growth continues unabated.

PHOTO 46. Downy mildew is often associated with purplish colour hues (without prominent shrivelling) of berries at a fairly advanced growing stage.

36 • A Guide to Grapevine Abnormalities in South Africa