Plant Viruses Online   

Descriptions and Lists from the VIDE Database

Subterranean clover stunt nanavirus

Index

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

Data collated by G.R. Johnstone, 1983. Revised by P.W.G. Chu, 1987.

Nomenclature

Synonyms

clover stunt virus, clover subterranean stunt virus.

Acronym

SCSV

Strains

Dickson isolate; Clandulla isolate; Ginnindera isolate a severe strain and Wattamondara isolate.

ICTV decimal code

79.0.P.1.003

Host range and symptoms

Natural host range and symptoms

Symptoms persist.
• Trifolium subterraneum, T. cernuum - mild or severe stunting, marginal chlorosis and puckering or cupping of leaflets, older leaves purple or crimson.
• Medicago lupulina, M. hispida var. denticulata, M. minima, Trifolium repens, T. glomeratum, Wisteria sinensis - typical stunting, shortening of petioles and internodes; chlorosis of young leaves.
• Phaseolus vulgaris - severe epinasty and leaves thickened, smaller and chlorotic; severe stunting and terminal necrosis, few or no seeds.
• Pisum sativum, Vicia faba - leaf size reduced, petioles and internodes shortened, leaf chlorosis and rolling.
• Trifolium dubium, T. pratense, Medicago arabica - typical stunting and yellowing on new growths.

Transmission

Transmitted by a vector; an insect; Aphis craccivora, A. gossypii, Myzus persicae, Macrosiphum euphorbiae; Aphididae. Transmitted in a persistent manner. Virus retained when the vector moults; does not multiply in the vector; not transmitted congenitally to the progeny of the vector; not transmitted by mechanical inoculation; transmitted by grafting; not transmitted by contact between plants; not transmitted by seed; not transmitted by pollen.

Ecology and control

Studies reported by Grylls and Butler (1956; 1959); O'Loughlin (1958); Grylls and Peak (1960; 1969); Peak et al. (1963); Gutierrez et al. (1971).

Geographical distribution

Spreads in Australia.

Experimental host range

Few (<3) families susceptible.

Diagnostically susceptible host species and symptoms

• Trifolium subterraneum cv. Mt Barker - severe stunting, rosetting, puckering and marginal chlorosis, reddening of older leaves.
• Medicago hispida var. denticulata - severe stunting, rosetting, puckering and marginal chlorosis, reddening of older leaves.
• Macroptilium lathyroides - severe stunting and small leaves, then marginal chlorosis and puckering of terminal leaves.
• Trigonella procumbens - extreme stunting and puckering of leaflets.
• Astragalus sinicus - stunting, leaf yellowing, size reduction and rolling down.

Diagnostically insusceptible host species

Gomphrena globosa, Capsella bursa-pastoris, Erodium moschatum.

Maintenance and propagation hosts

Trifolium subterraneum cv. Mt Baker, Pisum sativum cv. Greenfeast - propagation only.

Assay hosts (Local lesions or Whole plants)

Trifolium subterraneum (W).

Susceptible host species

• Arachis hypogaea
• Astragalus sinicus
• Crotalaria intermedia
• Crotalaria spectabilis
• Desmodium intortum
• Lablab purpureus
• Lens culinaris
• Macroptilium lathyroides
• Macrotyloma uniflorum
• Medicago
• Medicago arabica
• Medicago hispida
• Medicago hispida var. denticulata
• Medicago lupulina
• Medicago minima
• Medicago orbicularis
• Medicago polymorpha
• Medicago sativa
• Medicago scutellata
• Melilotus albus
• Melilotus indicus
• Onobrychis biebersteinii
• Onobrychis viciifolia
• Phaseolus vulgaris
• Pisum sativum
• Trifolium
• Trifolium cernuum
• Trifolium dubium
• Trifolium glomeratum
• Trifolium incarnatum
• Trifolium pannonicum
• Trifolium pratense
• Trifolium repens
• Trifolium subterraneum
• Trigonella procumbens
• Vicia faba
• Vicia sativa
• Vigna unguiculata
• Wisteria sinensis

Insusceptible host species

• Arachis hypogaea
• Beta vulgaris
• Brassica campestris ssp. napus
• Capsella bursa-pastoris
• Cicer arietinum
• Datura stramonium
• Erodium moschatum
• Glycine max
• Gomphrena globosa
• Lactuca sativa
• Lathyrus odoratus
• Linum usitatissimum
• Lupinus albus
• Medicago sativa
• Melilotus albus
• Senecio vulgaris
• Stellaria media
• Tetragonia tetragonioides
• Trifolium hybridum
• Trifolium pratense
• Trifolium repens
• Vitis rupestris

Families containing susceptible hosts

• Leguminosae-Papilionoideae (39/44)

Families containing insusceptible hosts

• Amaranthaceae (1/1)
• Caryophyllaceae (1/1)
• Chenopodiaceae (1/1)
• Compositae (2/2)
• Cruciferae (2/2)
• Geraniaceae (1/1)
• Leguminosae-Papilionoideae (10/44)
• Linaceae (1/1)
• Solanaceae (1 /1)
• Tetragoniaceae (1/1)
• Vitidaceae (1/1)

Comments on host-range

Host range data variable, probably resulting from strain differences or contaminants. All varieties of Trifolium subterraneum appear to be susceptible as well as all varieties of Phaseolus vulgaris. Many species of Medicago and Trifolium are susceptible.

Sources of host-range data

Grylls and Butler (1959); O'Loughlin (1958); Gutierrez et al. (1971); Smith (1966).

Physical and biochemical properties

Properties of particles in sap

Leaf sap contains many virions (when tested by ISEM). Electron microscopy: virus preparations are stable in AM, pH 6.5.

Purification method

Chu and Helms (1987). Use of cellulases helps purify virions.

Particle morphology

Virions isometric; not enveloped; 17-19 nm in diameter; angular in profile; without a conspicuous capsomere arrangement.

Physical properties

One sedimenting component in purified preparations. Density 1.34 g cm^-3 in CsCl (unfixed). A₂₆₀/A₂₈₀ ratio 1.35.

Biochemical properties

Virions contain 16-17 % nucleic acid; 83-84 % protein.

Genome consists of DNA; single-stranded; circular. Total genome size 3.36 kb. Genome of 7 parts (or more); largest (or only) genome part the largest 0.89 kb; the 2nd largest 0.88 kb; the 3rd largest 0.88 kb; the 4th largest 0.87 kb. Genomic nucleic acid isolated by Chu and Helms (1988): resuspend virus purified by sucrose density gradient in 50 mM tris-HCl buffer, pH 7.6, 1 mM EDTA, 100 mM Na-acetate, and extract with phenol and 2% SDS.

NCBI sequence data (Entrez search)

Sequence database accession code(s)

• S57687 Em(40)_vi:S57687 Gb(84)_vi:S57687 coat protein (component 3) subterranean clover stunt virus SCSV, F isolate, Genomic, 48 nt.
• U16730 Em(43)_vi:Sc16730 Gb(89)_vi:Scu16730 Subterranean clover stunt virus (SCSV1) gene, complete cds. 12/94 1,001bp.
• U16731 Em(43)_vi:Sc16731 Gb(89)_vi:Scu16731 Subterranean clover stunt virus possible replication asociated protein (SCSV2) gene, complete
• U16732 Em(43)_vi:Sc16732 Gb(89)_vi:Scu16732 Subterranean clover stunt virus (SCSV3) gene, complete cds. 12/94 991bp.
• U16733 Em(43)_vi:Sc16733 Gb(89)_vi:Scu16733 Subterranean clover stunt virus (SCSV4) gene, complete cds. 12/94 1,002bp.
• U16734 Em(43)_vi:Sc16734 Gb(89)_vi:Scu16734 Subterranean clover stunt virus coat protein (SCSV5) gene, complete cds. 12/94 998bp.
• U16735 Em(43)_vi:Sc16735 Gb(89)_vi:Scu16735 Subterranean clover stunt virus possible replication associated protein (SCSV6) gene, complet
• U16736 Em(43)_vi:Sc16736 Gb(89)_vi:Scu16736 Subterranean clover stunt virus (SCSV7) gene, complete cds. 12/94 988bp.

Features of proteins

Virion protein(s) one; M_r 19000; coat protein.

Cytopathology

Virions found in phloem. Inclusions absent from infected cells. Other cellular changes: phloem necrosis.

Taxonomy and relationships

nanavirus (the type species)

Best tests for diagnosis

Often occurs naturally with bean yellow mosaic and clover yellow mosaic viruses; ELISA tests are best to distinguish these viruses.

Comments and References

References

• Chu, P.W.G. and Helms, K. (1988). Virology 167: 38.
• Grylls, N.E. and Butler, F.C. (1956). J. Aust. Inst. agric. Sci. 22: 73.
• Grylls, N.E. and Butler, F.C. (1959). Aust. J. agric. Res. 10: 145.
• Grylls, N.E. and Peak, J.W. (1960). Aust. J. agric. Res. 11: 723.
• Grylls, N.E. and Peak, J.W. (1969). Aust. J. agric. Res. 20: 37.
• Gutierrez, A.P., Morgan, D.J. and Havenstein, D.E. (1971). J. appl. Ecol. 8: 69.
• O'Loughlin, G.T. (1958). J. Agric. Vic. 56: 385.
• Peak, J.W., Morley, F.H.W. and Grylls, N.E. (1963). Aust. J. agric. Res. 14: 639.
• Smith, P.R. (1966). Aust. J. agric. Res. 17: 875.

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.