Beetle vectors are recorded for most bromoviruses but the efficiency of such transmission is low. A long-standing report of transmission by nematodes has yet to be confirmed.
Virions are polyhedral, and all the same size, with a diameter of 27 nm.
RNA3 is slightly larger than RNA2, unlike other members of this family. The 2a protein is the smallest reported for viruses in the family (78.9 kDa).
Virus particles are quasi-spherical, with a diameter ranging from 25 to 35 nm, and have a poorly resolved surface structure.
Alfalfa mosaic virus (AMV) is transmitted in a non-persistent manner by at least 20 aphid species. AMV shares many properties at the molecular level with members of the genus Ilarvirus, which are not transmitted by aphids.
Jeremy R. Thompson, Tomás Canto, John P. Carr, Vicente Pallás and Dana Šafářová.
The citation for this ICTV Report chapter is the summary published as Thompson et al., (2025):
ICTV Virus Taxonomy Profile: Bromoviridae 2025, Journal of General Virology, 106: 0.002069.
A summary of this ICTV Report chapter has been published as an ICTV Virus Taxonomy Profile article in the Journal of General Virology, and should be cited when referencing this online chapter as follows:
Dulieu, P., Penin, P., Dulieu, H. & Gautheron, D. C. (1988). Purification of virus-like particles from Vicia faba and detection by ELISA in crude leaf extracts. Plant Sci 56, 9-14.
Rodrigo A. Valverde*
Endornaviridae Study Group Chair
Department of Plant Pathology and Crop Physiology
Louisiana State University Agricultural Center
Baton Rouge
LA 70803 USA
E-mail: [email protected]
Betaendornaviruses infect ascomycete fungi. They are characterized by having shorter genomes (<10.7 kb) than alphaendornaviruses, lack of a glucosyltransferase domain which is present in the majority of alphaendornaviruses, but all encode a methyltransferase (Figure 1. Betaendornavirus). Furthermore, studied members lack a site-specific nick near the 5′-end of the positive-sense strand.
Alphaendornaviruses infect plants, fungi and the oomycete Phytophthora sp. They are characterized by longer genomes (>11.9 kb) than those of genus Betaendornavirus and the majority code for a glucosyltransferase domain (Figure 1. Alphaendornavirus). A site-specific nick near the 5′-end of the positive-sense strand of the replicative form has been reported for several alphaendornaviruses.
