OCCURRENCE OF SOILBORNE SUGAR BEET VIRUSES TRANSMITTED BY POLYMYXA BETAE NORTHERN AND CENTRAL TURKEY
N.D. Kutluk Yilmaz, M.A. Sokmen
A survey was conducted to determine the incidence of Beet necrotic yellow vein virus (BNYVV), Beet soilborne virus (BSBV) and Beet virus Q (BVQ) and their vector Polymyxa betae in sugar beet fields in central and northern Turkey. A total of 510 soil samples were collected in 2004 and 2005. Three detection techniques were used: ELISA for BNYVV and BSBV, RT-PCR for BVQ and direct staining of bait plant root tissues for P. betae cystosori. Bait plant tests and ELISA showed that 54.3% of the soils contained viruliferous P. betae cystosori. BSBV single infections were the most prevalent (23.7%) followed by double infection with BNYVV (23.1%), and single infection of BNYVV (7.5%). It was also found that 31.4% of the roots were infested with aviruliferous P. betae cystosori while 14.3% of the roots did not contain any cystosori. Forty five samples were selected on the basis of their geographical locations and tested for the presence of BVQ by RT-PCR. However, BVQ was not detected in any sugar beet samples tested.