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

Paraquat phytotoxicity.

PHOTO 486. A further example of harmful interventions in these leaves resulting from direct contact with spray-drift of paraquat.

PHOTO 487. Although less invasive, phytotoxicity (yellowing/browning) of partial or total leaf surfaces may also be induced by paraquat fumes, especially when application takes place during warm weather conditions.

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