Runkelių rizomaniją sukeliančio viruso identifikacija ir molekulinė charakteristika

Rhizomania is a soil-borne disease that occurs throughout the major sugar beet growing regions of the world. It is caused by Beet necrotic yellow vein virus (BNYVV, a typical member of the genus Benyvirus). BNYVV has a multipartite RNA genome with all natural isolates containing four RNA species, although some isolates have a fifth RNA. BNYVV is transmitted by the obligate root-infecting parasite Polymyxa betae Keskin. Typical symptoms of rhizomania, also known as “root madness”, include root bearding, stunting, chlorosis of leaves, yellow veining and necrosis of leaf veins. The disease causes huge economic losses and is difficult to control. A survey detected BNYVV infection in three Lithuanian, ten Ukrainian and in one area of Kazakhstan. The virus isolates were mechanical inoculated to indicator plants, which were used for BNYVV propagation, purification and further analysis. BNYVV identification was confirmed by DAS ELISA, electron microscopy and PCR methods. BNYVV has three major (A, B and P) types, which can not be distinguished serologically. But using restriction fragment length polymorphism analysis, multiple RT-PCR and comparing the virus coat protein sequences it was determined that Lithuanian BNYVV isolates belong to A and B type, Ukrainian to A and the isolate from Kazakhstan – to P type. Also immunoenzyme system consisted of the obtained polyclonal antibodies after rabbit immunization with purified BNYVV and conjugate of polyclonal antibodies and horseradish peroxidase was developed. Such system can be successfully applied for diagnosis of BNYVV