First record of A and B type Beet necrotic yellow vein virus in sugar beets in Sweden

Natural infections of sugar beet with Beet necrotic yellow vein virus (BNYV V), the causal agent of rhizomania, have been detected for the first time i n Sweden in two small areas, one on the island of Oland and one in the Sout heastern part of Scania. Single strand conformation polymorphism analyses o f PCR products revealed that the infections on Oland were produced by A typ e BNYVV, whereas those in Scania were caused by the B type. This suggests t hat BNYVV has been introduced into Sweden at least twice. Alternatively, th e virus may have invaded sugar beet from unknown native hosts. BNYVV RNA 5 was not detected in the samples investigated.