|Common names:||flavescence dorée of grapevine|
|Causal agents:||Candidatus Phytoplasma vitis|
|Distribution:||Europe (France, Swizerland, Germany, Italy), United States, Australia|
Flavescence dorée (from French "Flavescence" : yellowing and "dorée" : golden) is a bacterial disease of the vine with the potential to threaten vineyards. The bacterial agent has recently been named Candidatus Phytoplasma vitis, and its vector is the leafhopper, Scaphoideus titanus. Infection may kill young vines and greatly reduce the productivity of old vines. It is classified as a phytoplasma disease belonging to the group generically termed grapevine yellows. Occurrences are in sporadic epidemics, and varieties vary in their sensitivity to it.
There is no cure for the moment and the way to manage the spreading is the uprooting of the infected plants.
Leaves become red or yellow depending on variety. Twigs stay soft. There is no cold hardening.
Ca. Phytoplasma vitis is part of the 16SrV group (group name: Elm yellows) in the Phytoplasma taxonomy.
Flavescence dorée first appeared in 1949 in the Armagnac region of south west France. Its insect vector, S. titanus, was originally native to the Eastern United States and Canada and is believed to have been introduced to Europe during World War II. Spreading steadily throughout France, by 1987 it had reached the wine growing regions of Cognac, Languedoc and northern and southern Rhône, and by 1992 the Loire Valley, and Bordeaux. Variants of the disease are found in Switzerland, Germany, Italy, New York state, and Australia.
Symptoms on German variety Scheurebe
- List of grape diseases
- black wood of grapevine or "Stolbur" or "Bois noir", another vine disease due to a Phytoplasma species