Molecular detection and identification of potato phytoplasmas in Russia
In Russia, phytoplasma diseases of potatoes have long been suspected to occur in several potato-growing regions on the basis of symptoms and the presence of insect vectors. Symptoms of Potato stolbur phytoplasma (‘Candidatus Phytoplasma solani’ – EPPO A2 List) are most prevalent, but round leaf disease, potato witches’ broom and potato purple top wilt also occur. During summer 2006, 33 potato plants showing symptoms of phytoplasma diseases (e.g. purple top, stunting, bud proliferation, aerial tubers) were collected from the regions of the Volga River, Central Russia and Northern Caucasus. PCR tests with different sets of primers detected the presence of phytoplasmas in 12 samples out of 33. RFLP analysis showed that among the 12 PCR positive potato samples, 10 presented identical or very similar RLFP profiles to stolbur phytoplasma and 2 presented profiles similar to those of the aster yellows phytoplasma group. According to the authors, this is the first confirmation by molecular procedures that stolbur phytoplasma ‘Ca. P. solani’ and phytoplasmas of the aster yellows group occur on potato crops in Russia.
Sources
Girsova N, Bottner KD, Mozhaeva KA, Kastalyeava TB, Owens, RA, Lee IM (2008) Molecular detection and identification of Group 16SrI and 16SrXII phytoplasmas associated with diseased potatoes in Russia. Plant Disease 92(4), p 654.