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

Yellow mosaic/veinbanding (173); confusing spots (174).

PHOTO 173. Discolouration patterns can at times be very confusing, thereby creating the impression that yellow mosaic and veinbanding occur in combination.

PHOTO 174. Another example where the incidence of chlorotic spots may cause confusion – thereby emphasising the necessity of subjecting suspect material to specific virus detection techniques.

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