International survey on grapevine yellows
Grapevine yellows corresponds to a group of diseases including grapevine flavescence dorée MLO (EPPO A2 quarantine pest transmitted by Scaphoideus titanus), bois noir disease (not transmitted by S. titanus), Vergilbungskrankheit, and other yellows observed in different parts of the world. These diseases cause similar symptoms, which in certain cases may be extremely serious. A specific ELISA test for grapevine flavescence dorée using polyclonal and monoclonal antibodies, was applied to try to clarify this complex situation of grapevine yellows in the world and to check whether some of these yellows are due to grapevine flavescence dorée MLO or are serologically related to it. Grapevine stems or leaves showing symptoms of grapevine yellows were collected from several parts of the world: France (138 samples), Italy (13), Switzerland (39), Israel (9), North America (31), South Africa (24) and Australia (26). The results showed that grapevine flavescence dor‚e MLO is only present in Southern France and Northern Italy (Friuli). In France, it was possible to clarify a very confusing situation, as all the symptomatic vines in the north-east of France (Bourgogne) reacted negatively, suggesting that the disease observed in this region is probably bois noir. No positive results were obtained from samples showing symptoms of grapevine yellows from Sicilia (IT), Emilia-Romagna (IT), Switzerland (western part and Ticino), Israel, USA (New York State), South Australia, or from samples showing symptoms of Shiraz decline disease (similar to other yellows but possibly related to a closterovirus) from South Africa. In addition, these results suggest that grapevine flavescence dorée is not serologically related to other yellows. The authors stress that their results do not guarantee the absence of grapevine flavescence dorée MLO from the areas where other yellows were found. They also stress that the other yellows are economically important and do present a phytosanitary risk.
Sources
Kuszala, C.; Cazelles, O.; Boulud, J.; Credi, R.; Granata, G. Kriel, G.; Magarey, P.; Magnien, C.; Pearson, R.C.; Refatti, E.; Tanne, E.; Caudwell, A. (1993) Contribution … l'étude des jaunisses de la vigne dans le monde. Prospection par test ELISA spécifique du mycoplasma-like organism (MLO) de la flavescence dorée.
Agronomie, 13 (10), 929-933.