'Incurable' grape disease devasting French vineyards

French winemakers demand action on 'incurable' grape disease devastating vines

"French winemakers have demanded emergency funding to deal with an "incurable" grape disease which they fear could become as devastating as a 19th-century plague that almost destroyed the nation's vineyards...The fungal disease, esca, has infected 13 per cent of France's vines this year, costing the industry more than €1 billion (£790 million). "

More on the Esca (Grape Measles)
Pathogen: Nine species of fungi in the genus Phaeoacremonium.

SYMPTOMS

Affected leaves display small, chlorotic interveinal areas that enlarge and dry out. Foliage symptoms are frequently called "esca." In red varieties dark red margins surround the dead interveinal areas. Severely affected leaves may drop and canes may dieback from the tips. Symptoms may occur at any time during the growing season but are most prevalent during July and August. On berries, small, round, dark spots, each bordered by a brown-purple ring, may occur. These spots may appear at any time between fruit set and ripening. In severely affected vines the berries often crack and dry on the vine or are subject to spoilage.

What if esca disease of grapevine were not a fungal disease?
This article takes a systemic view "Consequently the presumed esca-associated fungal pathogens are most likely saprobes decaying already senescent or dead wood resulting from intensive pruning, frost or other mecanical injuries as grafting. The cause of esca disease therefore remains elusive and requires well executive scientific study. These results question the assumed pathogenicity of fungi in other diseases of plants or animals where identical mycota are retrieved from both diseased and healthy individuals."