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

Dead-arm.

PHOTO 54. A typical example of black tissue discolouration which accompanies the longitudinal cracks on basal internodes of Gamay noir shoots.

PHOTO 55. In this instance practically the entire circumference of the shoot has been invaded by dark brown to black tissue discolouration, while longitudinal cracks appear less prominent.

42 • A Guide to Grapevine Abnormalities in South Africa