Incursion of bois noir phytoplasma on grapevine in Canada
During summer and autumn 2006, a survey on grapevine phytoplasma was carried out in Canadian vineyards. Grapevines imported from Europe and established grapevines were observed for the presence of typical symptoms of grapevine yellows. Samples were collected and tested from 155 grapevines. One plant located in the lower Okanagan Valley in British Columbia tested positive for the presence of a phytoplasma. Further analysis confirmed the presence of the bois noir phytoplasma (Stolbur phytoplasma – EPPO A2 List) which is of quarantine significance to Canada. No other phytoplasmas (i.e. flavescence dorée or Western X disease) was detected. This infected grapevine was part of a lot of 1;965 plants which had been imported from Europe in 2006. The whole lot was destroyed.
In 2007, 2 grapevines were also found infected by bois noir in Ontario. These plants had been imported from France, before mandatory hot water treatments were required for imports of grapevines to Canada. All infected plants were destroyed in November 2007. Further surveys carried out in the vicinity of these infected plants did not detect other infections. It is also noted that the known vector of bois noir, Hyalesthes obsoletus, does not occur in North America. It is felt that bois noir has been eradicated from Canada but surveys will be carried out during successive growing seasons to verify its absence.
The pest status of bois noir phytoplasma (Stolbur phytoplasma) in Canada is officially declared as follows: Absent, pest eradicated.
Rott M, Johnson R, Masters C, Green M (2007) First report of bois noir phytoplasma in grapevine in Canada. Plant Disease 91(12), p 1682.
INTERNET (last retrieved in 2008-04)
NAPPO Phytosanitary Alert System. Canada Official Pest Reports (2007-12-21) Bois noir phytoplasma infected plants found in Ontario, Canada. http://www.pestalert.org/oprDetail.cfm?oprID=303