Fig 2. Comparison of the genome or segment sizes in the three types of viral genome organization.

The listed families or genera are those with significant differences in genome architectures. Not all viral families are represented in this figure. We have chosen families with a large range of total genome sizes, but avoiding those monopartite virus groups with an immense genome that would have compressed too much the scale of the graphic. We also show viral families containing both mono- and multipartite member species. The size range of whole genomes and that of individual segments are illustrated by black and grey lines, respectively. All size data come from the website (http://viralzone.expasy.org/), from the ninth International Committee on Taxonomy of Viruses (ICTV) report, and from specific literature. *All genera of the family Virgaviridae except the genus Tobamovirus are composed of multipartite virus species. **The genus Begomovirus is composed of both monopartite and bipartite virus species. ***All genera of the family Closteroviridae are composed of monopartite virus species, except for the genus Crinivirus. ****All genera of the family Geminiviridae are composed of monopartite virus species, except for the genus Begomovirus. *****All genera of the family Potyviridae are composed of monopartite virus species, except for the genus Bymovirus.