| "candidatus phytoplasma americanum", a phytoplasma associated with a potato purple top wilt disease complex. | potato purple top wilt (ppt) is a devastating disease that occurs in various regions of north america and mexico. at least three distinct phytoplasma strains belonging to three different phytoplasma groups (16sri, 16srii and 16srvi) have been associated with this disease. a new disease with symptoms similar to ppt was recently observed in texas and nebraska, usa. two distinct phytoplasma strain clusters were identified. one belongs to the 16sri phytoplasma group, subgroup a, and the other is a n ... | 2006 | 16825635 |