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

2,4-D phytotoxicity (492); 2,4,5-T toxicity (493).

PHOTO 492. In this instance severe damage was caused where the grapevine in question was subjected to direct contact with the spray-drift of a herbicide with 2,4-D as its active ingredient. Note the curling effect of shoots, as well as the incidence of cracks in the trunk.

PHOTO 493. Serious toxicity interventions may occur where grapevines are exposed to spray-drift/ fumes of herbicides where 2,4,5-T is the active ingredient. Cracks on shoots, petioles and peduncles, as well as the shrub-like appearance of short and thick aerial roots, are considered characteristic in such cases.

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