Black Foot Disease

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In California, Cylindrocarpon causes "black foot disease" in grape, affecting mainly young vines up to eight years old.

Cylindrocarpon is known to occur in all major viticulture regions of the world, but the disease is not well understood. It's importance in B.C.'s vineyards remains to be seen.

Cylindrocarpon spp. was found in B.C. for the first time during a 2007-2009 survey of grape decline problems by Agriculture and Agri-Food Canada (O'Gorman, Haag & Sholberg). It was isolated from vines ranging from 3-15 years old in several vineyards. Infection was associated with both a gradual and rapid decline of vines.

The following information is based on information from California and other viticultural areas.

Symptoms

Roots show black, sunken, necrotic lesions. In a cross section, the base of the trunk appears necrotic, and xylem vessels may be black in colour. Leaves may appear to be water stressed or scorched, and vines may be stunted and/or killed.

Cylindrocarpon may occur in combination with other plant pathogens.

Spread

Cylindrocarpon is a common soil-borne fungus that causes root rot in many plant species. It survives in soil as mycelium and also produces conidia (spores) and chlamydospores (spores that can survive adverse conditions).

Research in South Africa has shown that nursery soils can be a source of inoculum and that the disease can be carried on nursery plants.

Management

• Plant healthy vines with no sign of root deterioration or discolouration in the vascular tissue.
• In South Africa, hot water treatment has been shown to reduce the level of Cylindrocarpon infection in nursery stock. (Hot water treatment at a similar temperature and duration is required for vines imported from France or Germany for the prevention of phytoplasma diseases.)
• There are no fungicide treatments for Cylindrocarpon available in Canada.