Molecular Plant Pathology – Pathogen Profiles

Barley yellow dwarf virus: Luteoviridae or Tombusviridae?

W. Allen Miller, Sijun Liu and Randy Beckett

351 Bessey Hall, Iowa State University, Ames, Iowa 50011, USA

Taxonomy:BYDV is in genus Luteovirus, family Luteoviridae. BYDV includes at least two serotypes or viruses: BYDV-PAV and BYDV-MAV. The former BYDV-RPV is now Cereal yellow dwarf virus-RPV (CYDV-RPV). CYDV is in genus Polerovirus, family Luteoviridae. Genus Luteovirus shares many features with family Tombusviridae.
Physical properties:25 nm icosahedral (T = 3) virions. One major (22 kDa) and one minor (50-55 kDa) coat protein. 5.6-5.8 kb positive sense RNA genome with no 5′-cap and no poly(A) tail.
Host Range:Most grasses. Most important in oats, barley and wheat. Also infects maize and rice.
Disease symptoms:Yellowing and dwarfing in barley, stunting in wheat; reddening, yellowing and blasting in oats. Some isolates cause leaf notching and curling.
Key attractions:Model for the study of circulative transmission of aphid-transmitted viruses. Plethora of unusual translation mechanisms. Evidence of recombination in recent evolutionary history creates taxonomic ambiguity. Economically important virus of wheat, barley and oats, worldwide.
Useful meetings / web sites:International symposium: Barley Yellow Dwarf Disease: Recent Advances and Future Strategies’, CIMMYT, El Batan, Mexico, 1-5 September 2002.