Bean yellow mosaic virus is a plant pathogenic virus in the genus Potyvirus and the virus family Potyviridae. Like other members of the Potyvirus genus, it is a monopartite strand of positive-sense, single-stranded RNA surrounded by a capsid made for a single viral encoded protein. The virus is a filamentous particle that measures about 750 nm in length. This virus is transmitted by species of aphids and by mechanical inoculation.