DETECTION OF BEET NECROTIC YELLOW VEIN VIRUS USING REVERSE TRANSCRIPTION AND POLYMERASE CHAIN-REACTION

A diagnostic test based on reverse transcription followed by the polym erase chain reaction (RT-PCR) was developed for the detection of beet necrotic yellow vein virus (BNYVV). A specific 500-base-pair fragment was amplified from the read-through region of the coat protein gene lo cated on RNA-2. The viral origin of the amplified product was confirme d by sequencing, with the sequence obtained having 94.5% homology with published sequence data for BNYVV. The assay gave a sensitivity of 80 0 times that of a TAS-ELISA and 50 times that of an amplified TAS-ELIS A method. A range of BNYVV isolates from the UK and worldwide could be detected by this test, either as mechanically inoculated Chenopodium quinoa leaves or infected sugar beet roots. Use of the assay in routin e diagnostic tests allowed a reduction of time needed for the detectio n of Rhizomania in soils from 7 to 4 weeks.