Virus Taxonomy has been managed by the International Committee on Taxonomy of Viruses (ICTV). It was originally founded in Moscow in 1966 to provide international standards for nomenclature and classification of viruses.  The ICTV meeting has been held with the International Congress of Virology.

 Proposed name of new or existing viruses are vote for the accepted taxonomic proposals by ICTV Executive Committee meeting.  The approved results have been published as the ICTV reports providing standard names and taxa of viruses all over the world.  The recent and current report is the 7th ICTV Report (Van Regenmortel et al., 2000).  Plant Virus taxonomy is in charge of Plant Virus Subcommittee.

The current ICTV report contains plant viruses of 951 species in 79 genera in 17 families, though 24 of the 79 genera are floating genera, that is, they are not included in any established families.

Virus species is 　" A virus is defined as a polythetic class of viruses that constitute a replicating lineage and occupies a particular ecological niche" by the current ICTV Report.　  This definition is very knotty, but it is considered appropriate for viruses.  It means that a virus species is not a pure nucleic acid sequence.  Discrimination of virus species is still difficult, and criteria for the virus species are variable in deferent families and we have no universal standards.

As a general rule, virus names are written started with a capital and in italic like Tobacco mosaic virus.  If a virus name contains proper noun, the word is also capitalized e. g. Grapevine Algerian latent virus.  Styles such as tobacco mosaic virus polymerase, a preparation of tobacco mosaic virus, some species of tobamoviruses, or the potyviruses are also allowed.  However, only the virus name with distinct species status can be italicized.  Tentative species, that is, viruses not classified into established genera by ICTV are not written in italic.  Style with genus name, i.e., tobacco mosaic tobamovirus are abolished.  Family and genus names are also written in italic.

Van Regenmortel, M.H.V., Bishop, D.H.L., Fauquet, C.M., Mayo, M.A., Maniloff, J. and Calisher, C.H. 1997. Guidelines to the demarcation of virus species.  Arch. Virol. 142:1505-1518.

Van Regenmortel, M.H.V., Fauquet, C.M., Bishop, D.H.L., Carstens, E.B., Estes, M.K., Lemon, S.M., Maniloff, J., Mayo, M.A., McGeoch, D.J., Pringle, C.R. and Wickner, R.B. 2000.  Virus taxonomy. Seventh report of the International Committee on Taxonomy of Viruses. Academic Press, San Diego.