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Summary: In Canada, seven phytoplasma taxa have been detected in various crops. Aster yellows, the primary vector of which is the leafhopper Macrosteles quadrilineatus, is the most common and widespread. Ash yellows and pear decline have caused economic problems for several decades, while bois noir, a quarantinable disease in Canada, was detected in Ontario and British Columbia for the first time only recently. Because of their cryptic nature, phytoplasmas are difficult to manage; quarantine measures and insecticide sprays remain the most common control measures. However, integrated pest management techniques using beneficial insects, biotechnology, and plant resistance are emerging.

Link: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8443758&fileId=S0008347X00000687