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

Snails (349); fruit fly (350).

PHOTO 349. Typical feeding patterns on leaves are depicted, in conjunction with the snails’ appetite for young tendrils. With regard to identification procedures, note the slimy tracks and characteristic excretions in the 16:00 position.

PHOTO 350. Direct damage caused by the feeding activities of fruit fly larvae is associated with brown- coloured tunnels under the skin of ripening berries. Indirect damage also occurs as a result of the entry provided to secondary rotting organisms by fruit fly stings during the laying of their eggs.

A Guide to Grapevine Abnormalities in South Africa • 223