Submitted to: Encyclopedia of Virology
Publication Type: Book / Chapter
Publication Acceptance Date: January 25, 2008
Publication Date: September 30, 2009
Repository URL: http://hdl.handle.net/10113/37366
Citation: Domier, L.L. 2009. Barley Yellow Dwarf Virus. In: Mahy, B.W.J. and Van Regenmortel, M.H.V. Desk Encyclopedia of Plant and Fungal Virology. Oxford:Academic, c2010., p. 100-107. Technical Abstract: Barley yellow dwarf (BYD) is the most widespread and economically important virus disease of cereals. The viruses causing BYD were initially grouped based on common biological properties, including persistent and often strain-specific transmission by aphids and induction of yellowing symptoms. The severity and distribution of BYD infections are dependent on the sensitivity of host plants and meteorological conditions that favor movement and reproduction of vector aphids. Initially the viruses causing BYD were considered strains of Barley yellow dwarf virus (BYDV) and named for their principle aphid vectors. With the advent of immunological detection techniques and nucleotide sequence analysis, the viruses were separated into two genera, Luteovirus and Polerovirus, within the family Luteoviridae. Currently, seven species, BYDV-MAV, BYDV-PAS, BYDV-PAV, BYDV-RMV and BYDV-SGV, and Cereal yellow dwarf virus-RPS (CYDV-RPS) and CYDV-RPV are recognized. BYDVs and CYDVs share a common particle morphology (nonenveloped 25-nm icosahedra), with virus particles composed of one major and one minor capsid protein and a single molecule of positive-sense single-stranded RNA. BYDVs and CYDVs genomic RNAs are about 5.6 kb in length and contain five to six open reading frames (ORFs). The ORFs are expressed through multiple strategies, including frameshifting, leaky scanning, termination codon readthrough, and long-distance RNA-RNA interactions. Even though capsid proteins of BYDVs and CYDVs are highly conserved, RNA-dependent RNA polymerases of the BYDVs and CYDVs are distantly related evolutionarily.