Detection and identification of the blackeye cowpea mosaic strain of Bean common mosaic virus in seeds of Vigna unguiculata sspp. from North Vietnam

摘要

Twenty-seven seed samples of catjang bean and yard long bean ( Vigna unguiculata sspp.) collected from different provinces of North Vietnam were tested for the presence of the blackeye cowpea mosaic strain of Bean common mosaic virus (BCMV-BlCM), Cowpea aphid-borne mosaic virus, Cowpea mosaic virus, Cucumber mosaic virus and Southern cowpea mosaic virus using a growing-on test, ELISA, bioassay and electron microscopy. Among the 27 seedlots tested, eight catjang bean and five yard long bean seedlots were found to be infected with BCMV-BlCM serotype B. The identity of one of these isolates as BCMV-BlCM was further supported by nucleotide sequencing in the 3' region of the genome. The incidence of seeds carrying transmissible virus ranged from 0.8 to 12.4%. In most cases, only symptomatic seedlings in a growing-on test were found infected with the virus. This is the first record of BCMV-BlCM in catjang bean and yard long bean grown in North Vietnam.