Plant Viruses Online   

Descriptions and Lists from the VIDE Database

Kennedya yellow mosaic tymovirus

Index

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

Data collated by A.J. Gibbs, 1981. Revised 1989.

Nomenclature

Acronym

KYMV

Strains

Port Douglas (Mount Jukes), Jervis Bay, Wapengo; these being the type members of three geographically separate strains found in north Queensland, central coast N.S.W. and south coast N.S.W. respectively.

ICTV decimal code

77.0.1.0.009

Host range and symptoms

Natural host range and symptoms

Symptoms persist (and are often bright).
• Kennedya rubicunda, Desmodium triflorum, D. scorpiurus, Indigofera australis - mild chlorotic local lesions, systemic blotchy yellow mosaic.

Transmission

Virus transmitted by mechanical inoculation; not transmitted by contact between plants; not transmitted by seed; not transmitted by pollen.

Geographical distribution

Spreads in Australia (the eastern coastal region).

Experimental host range

Few (<3) families susceptible.

Diagnostically susceptible host species and symptoms

• Glycine max - blotchy systemic yellow mosaic.
• Kennedya rubicunda - systemic yellow mosaic.
• Phaseolus vulgaris cv. Redland Pioneer, Pisum sativum - chlorotic local lesions; then systemic yellow mosaic.
• Vigna radiata - necrotic local lesions; systemic leaf malformation.
• Datura stramonium, Nicotiana glutinosa - chlorotic local lesions; not systemic.

Diagnostically insusceptible host species

Lycopersicon esculentum, Nicotiana clevelandii.

Maintenance and propagation hosts

Pisum sativum cv. Early Massey, Glycine max.

Assay hosts (Local lesions or Whole plants)

Phaseolus vulgaris cv. Redland Pioneer (L), Pisum sativum cv. Massey (W), Vigna radiata (L).

Susceptible host species

• Cajanus cajan
• Clitoria ternatea
• Datura stramonium
• Desmodium scorpiurus
• Desmodium triflorum
• Glycine max
• Indigofera australis
• Kennedya rubicunda
• Lupinus angustifolius
• Macrotyloma uniflorum
• Nicotiana glutinosa
• Phaseolus vulgaris
• Pisum sativum
• Vigna angularis
• Vigna radiata
• Vigna unguiculata
• Vigna unguiculata ssp. sesquipedalis

Insusceptible host species

• Chenopodium amaranticolor
• Chenopodium quinoa
• Cucumis sativus
• Gomphrena globosa
• Lotus corniculatus
• Lycopersicon esculentum
• Medicago sativa
• Nicotiana clevelandii
• Trifolium incarnatum
• Trifolium pratense
• Trifolium repens
• Vicia faba
• Vicia sativa

Families containing susceptible hosts

• Leguminosae-Papilionoideae (15/22)
• Solanaceae (2/4)

Families containing insusceptible hosts

• Amaranthaceae (1/1)
• Chenopodiaceae (2/2)
• Cucurbitaceae (1/1)
• Leguminosae-Papilionoideae (7/22)
• Solanaceae (2/4)

Sources of host-range data

Dale and Gibbs (1976); Gibbs (1978) and unpublished data.

Physical and biochemical properties

Properties of particles in sap

TIP: 65-70 °C. LIV: 10-100 days. DEP: log₁₀ minus 5-6. Infectivity of sap not changed by treatment with di-ethyl ether. Leaf sap contains many virions.

Purification method

Gibbs (1978).

Particle morphology

Virions isometric; not enveloped; 28 nm in diameter; rounded in profile; with a conspicuous capsomere arrangement.

Physical properties

Two sedimenting components in purified preparations; sedimentation coefficient of the fastest; B 110 S; of the other(s) 54 S. Isoelectric point pH 3.3-3.57. A₂₆₀/A₂₈₀ ratio 0.81 (T), or 1.69 (B).

Biochemical properties

Virions contain 34.1 % nucleic acid; 65.9 % protein; 0 % lipid.

Genome consists of RNA; single-stranded; linear. Total genome size 6.362 kb. Genome unipartite; largest (or only) genome part 6.362 kb. Base composition 15.1 % G; 22.5 % A; 39.4 % C; 23 % U. 5´ terminus of RNA has a methylated nucleotide cap. Infectivity retained when deproteinised with phenol or detergent. Poly A region absent. Additional factor not required for infectivity. Nucleotide sequence references: Ding et al. (1990).

NCBI sequence data (Entrez search)

Sequence database accession code(s)

• D00637 Em(40)_vi:MTYCG01 Gb(84)_vi:KYVCGA Kennedya yellow mosaic virus genome, complete sequence. 11/90 6,362bp.
• M15286 Em(40)_vi:TYMTY3KY Gb(84)_vi:KYV3KYMV Kennedya yellow mosaic virus 3´ end which can form a tRNA-like structure. 11/90 83bp.
• M58310 Em(40)_vi:KYVRRLT Gb(84)_vi:KYVRRLT Kennedya yellow mosaic virus 3´ terminal tRNA-like structure. 8/91 84bp. 3 sequences.

Features of the genome

Non-genomic nucleic acid found in the virions; is of an unusual type of structure (mRNA like).

Features of proteins

Virion protein(s) one; M_r 19602.

Replication

Genome replicates in association with chloroplasts (in the vesicles). Coat protein mRNA translated in the cytoplasm. Replication does not depend on a helper virus.

Cytopathology

Virions found in all parts of the host plant; in cytoplasm. Inclusions absent from infected cells. Other cellular changes: vesiculation of the chloroplasts outer membrane.

Taxonomy and relationships

Tymovirus

Virus(es) with serologically related virions

Turnip yellow mosaic, clitoria yellow vein and okra mosaic, closely; desmodium yellow mottle and cacao yellow mosaic viruses more distantly.

Additional comments on relationships

CDNA-RNA hybridization tests correlate with the serological relationships, but also show an unexpected close relationship with eggplant mosaic tymovirus, which is serologically very distantly related to kennedya yellow mosaic virus.

Comments and References

References

• Blok, J., Gibbs, A.J. and Mackenzie, A. (1987). Arch. Virol. 96: 225.
• Dale, J.L., Gardiner, J.E. and Gibbs, A.J. (1975). Aust. Pl. Path. Soc. Newsl. 4: 13.
• Dale, J.L. and Gibbs, A.J. (1976). Aust. J. biol. Sci. 29: 397.
• Ding, S., Keese, P. and Gibbs, A.J. (1990). J. gen. Virol. 71: 925.
• Gibbs, A.J. (1978). CMI/AAB Descr. Pl. Viruses No. 193, 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.