PHYLOGENETIC JUSTIFICATION FOR SPLITTING THE RYMOVIRUS GENUS OF THE TAXONOMIC FAMILY POTYVIRIDAE - BRIEF REPORT

The Potyviridae family has been divided into four genera on the basis of vector transmission, as follows: Potyvirus genus (aphid), Rymovirus genus (mite), Bymovirus genus (fungus) and Ipomovirus genus (whitefly ). However recent sequence comparisons of the coat protein and 3' NCR regions of the potyviruses have demonstrated that the rymoviruses appe ar to be a group of two unrelated clusters namely Ryegrass Mosaic Viru s (RGMV), Agropyron Mosaic Virus (AgMV) and Hordeum Mosaic Virus (HoMV ) in one group and Wheat Streak Mosaic Virus (WSMV) and Brome Streak M osaic Virus (BrSMV) in the second group. We therefore propose that RGM V, AgMV and HoMV remain in the genus Rymovirus and WSMV and BrSMV form a separate genus, possibly the Whestrevirus genus.