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

Shiraz disease.

PHOTO 234. Small and poorly developed flower clusters may be considered some of the most important contributing factors to reduced yields (associated with Shiraz disease).

PHOTO 235. Dieback of an allocated two-bud spur during winter pruning contributes royally to the development of infertile water shoots the following growing season – obviously resulting in drastic reductions in crop size.

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