Plant Viruses
Online 
Descriptions and Lists from
the VIDE Database
Alfamoviruses:
Bromoviridae
Index
Nomenclature
ICTV reference
Definitive species
Host range and
symptoms
Natural host range and symptoms
Symptoms
persist, or disappear soon after infection.
Transmission
Transmitted by a vector; an insect;
Aphididae. Transmitted in a non-persistent manner. Virus transmitted by
mechanical inoculation; transmitted by grafting; not transmitted by contact
between plants; transmitted by seed; transmitted by pollen to the seed.
Experimental host range
Many (>9) families
susceptible.
Susceptible host species
Insusceptible host species
Families containing susceptible hosts
Families containing insusceptible
hosts
Physical and
biochemical properties
Properties of particles in sap
TIP:
60-65 °C. LIV: 1-4 days. DEP: log10 minus 3-4. Infectivity of sap not changed
by treatment with di-ethyl ether. Leaf sap contains many virions.
Particle morphology
Virions bacilliform; not enveloped;
30-56 nm in length; 18 nm wide.
Physical properties
Four sedimenting components in
purified preparations; sedimentation coefficient 94 S; of the other(s)
66-82 S. Density 1.381-1.385 g cm-3 in CsCl. Isoelectric point pH
4.6. A260/A280 ratio 1.7-1.8.
Biochemical properties
Virions contain 16 % nucleic acid;
84 % protein; 0 % lipid.
Genome consists of RNA; single-stranded; linear. Total genome size 8.27
kb. Genome of three parts; largest (or only) genome part 3.64 kb; the 2nd
largest 2.59 kb; the 3rd largest 2.04 kb. Base composition 23 % G; 25 % A; 23 %
C; 29 % U. 5´ terminus of RNA has a methylated nucleotide cap. Infectivity
retained when deproteinised with proteases, or decreased when deproteinised with
proteases; retained when deproteinised with phenol or detergent. Poly A region
absent. Additional factor required for infectivity. Genome has no
tRNA-like activity.
Features of the genome
Non-genomic nucleic acid
found in the virions; is subgenomic mRNA. Sub-genomic mRNA
found in infected cells.
Features of proteins
Virion protein(s) one;
Mr 24250.
Replication
Replication does not depend on a helper
virus.
Cytopathology
Virions found in cytoplasm, or in
chloroplasts. Inclusions present in infected cells; are unusual in shape; they
contain virions.
Taxonomy and
relationships
Viral family : Bromoviridae.
Illustrations
Cite this publication as:
Brunt, A.A., Crabtree, K., Dallwitz, M.J., Gibbs, A.J., Watson, L. and Zurcher, E.J. (eds.)
(1996 onwards).
`Plant Viruses Online: Descriptions and Lists from the VIDE Database.
Version: 20th August 1996.' URL
http://biology.anu.edu.au/Groups/MES/vide/
Dallwitz (1980)
and
Dallwitz, Paine and Zurcher (1993)
should also be cited.
Please send comments, corrections and suggestions to:
vide-manager@biology.anu.edu.au
