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

Magnesium deficiencies.

PHOTO 472. In the case of red grape cultivars, magnesium deficiencies are associated with an interveinal reddening of leaves.

PHOTO 473. In extreme cases, leaf edge necrosis may be induced by magnesium deficiencies, as can be seen in the 09:00 position in this example.

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