Plant Viruses Online   

Descriptions and Lists from the VIDE Database

Saguaro cactus (?) carmovirus

Index

• Nomenclature
• Host range, transmission and symptoms
• Physical and biochemical properties
• Taxonomy and relationships
• Comments and References

Data collated by J.H. Tremaine, 1988.

Nomenclature

Synonyms

cactus Saguaro virus.

Acronym

SCV

ICTV decimal code

74.0.2.0.011

Host range and symptoms

Natural host range and symptoms

Symptoms none.
• Carnegiea gigantea, Chamaecereus sylvestrii - symptomless.

Transmission

Virus transmitted by mechanical inoculation.

Geographical distribution

Found, but with no evidence of spread, in Arizona, U.S.A. or Germany.

Diagnostically susceptible host species and symptoms

• Chenopodium capitatum - systemic vein-clearing and necrosis.
• Chenopodium amaranticolor, C. quinoa - local lesions, not systemic.
• Gomphrena globosa - local lesions, systemic spots.

Maintenance and propagation hosts

Chenopodium capitatum.

Assay hosts (Local lesions or Whole plants)

Chenopodium amaranticolor (L), C. quinoa (L).

Susceptible host species

• Carnegiea gigantea
• Chamaecereus sylvestrii
• Chenopodium amaranticolor
• Chenopodium capitatum
• Chenopodium quinoa
• Gomphrena globosa

Families containing susceptible hosts

• Amaranthaceae (1/1)
• Cactaceae (2/2)
• Chenopodiaceae (3/3)

Physical and biochemical properties

Properties of particles in sap

TIP: 55-65 °C. LIV: 34 days. DEP: log₁₀ minus 4. Leaf sap contains many virions.

Purification method

Nelson and Tremaine (1975).

Particle morphology

Virions isometric; not enveloped; 32 nm in diameter; rounded in profile; without a conspicuous capsomere arrangement.

Physical properties

One sedimenting component in purified preparations; sedimentation coefficient 118 S. Density 1.33 g cm^-3 in CsCl. Isoelectric point pH 3.5, 5, and 5.5.

Biochemical properties

Virions contain 17 % nucleic acid; 83 % protein; 0 % lipid.

Genome consists of RNA; single-stranded; linear. Total genome size 4.2 kb. Genome unipartite; largest (or only) genome part 4.2 kb. Base composition 29 % G; 24 % A; 21 % C; 27 % U.

Features of the genome

Non-genomic nucleic acid found in the virions; is subgenomic mRNA.

Features of proteins

Virion protein(s) one (and degraded protein and dimers 5%); M_r 38900; coat protein. Method of preparation: Nelson and Tremaine (1975). Amino acid composition: Nelson and Tremaine (1975).

Replication

Replication does not depend on a helper virus.

Cytopathology

Virions found in cactus buds, flowers and fruit.

Taxonomy and relationships

Possible Carmovirus: Tombusviridae

Virus(es) with serologically unrelated virions

Carnation mottle and turnip crinkle viruses.

Additional comments on relationships

Like carmoviruses it produces dsRNAs, and of a similar size (1.7 and 1.5 kbp) (Morris and Carrington, 1985).

Comments and References

References

• Morris, T.J. and Carrington, J.C. (1985). In: The Plant Viruses, Vol. 3, Polyhedral Virions with Monopartite RNA Genomes, p. 73 ed. R. Koenig. Plenum Press, New York.
• Milbrath, G.M. and Nelson, M.R. (1972). Phytopathology 62: 739.
• Nelson, M.R. and Tremaine, J.H. (1975). Virology 65: 309.
• Nelson, M.R., Yoshimura, M.A. and Tremaine, J.H. (1975). CMI/AAB Descr. Pl. Viruses No. 148, 4 pp.

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: 20^th August 1996.' URL http://biology.anu.edu.au/Groups/MES/vide/

Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993) should also be cited.