Emerging viral threats Dimitre Mollov, Ben Lockhart, David Zlesak, and Maher Al Rwahnih USDA ARS University of Minnesota University of Wisconsin, River Falls University of California Davis Virus Diseases of Roses: 1930-2005 Rose diseases caused by identified viruses – Rose mosaic caused by • Prunus necrotic ringspot virus (PNRSV) • Apple mosaic virus (ApMV) • Arabis mosaic virus (ArMV) • Strawberry latent ringspot virus (SLRSV) Symptoms observed early in the season Compendium of Rose Diseases, R.K. Horst, Ed., The American Phytopathological Society, St. Paul, MN Virus Diseases of Roses: 2005-2010 • Rose yellow vein virus (RYVV), Caulimoviridae • Rosa rugosa leaf distortion virus (RrLDV), Tombusviridae (= Rose yellow leaf virus (RoYLV) • Rose yellow mosaic virus (RoYMV), Potyviridae • Rose necrotic mosaic virus (RNMV), (filamentous particles observed) • Rose transient mosaic virus (RoTMV) – • Rose cryptic virus 2 Rose yellow vein virus (RYVV) Caulimoviridae 200 nm Rose yellow mosaic virus (RoYMV) Potyviridae Rose yellow mosaic virus (RoYMV) Rosa rugosa leaf distortion virus (RrLDV) =Rose yellow leaf virus, Tombusviridae Rosa rugosa leaf distortion virus (RrLDV) =Rose yellow leaf virus, Tombusviridae 100 nm Virus Diseases of Roses: 2015-2017 Rosa setigera Rosa setigera Rose yellow vein virus: 63% Rosa setigera Amalgavirus: 3.5kb ds RNA virus Blueberry latent virus 50% Blueberry latent virus: an amalgam of the Partitiviridae and Totiviridae. Martin, Zhou, and Tzanetakis, Virus Res 2011 Blackberry chlorotic ringspot virus: 5.8 kb – 96% Strawberry necrotic shock virus: 2.9 kb – 80% Rosa ‘Hugh Dickson’ • Rose yellow vein virus: 96% • Rose partitivirus: 100% Rosa ‘Hugh Dickson’ Compete genome of a new rhabdovirus Rosa wichurana Blackberry chlorotic ringspot virus: 100% Rose yellow vein virus: 99% Rosa wichurana Carlavirus contigs (76%) Rosa ‘Morden Blush’ ‘Double wide bloom’ Rose yellow vein virus (RYVV) Caulimoviridae RYVV phylogenetic analysis Rosadnavirus Detection RYVV RoYMV RrLDV MP CP .