Plant Viruses Online   

Descriptions and Lists from the VIDE Database

Cassia severe mosaic (?) closterovirus

Index

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

Data collated by R.G.T. Hicks, 1991.

Nomenclature

ICTV decimal code

17.0.1.T.DE.2

Host range and symptoms

Natural host range and symptoms

Symptoms persist. Symptoms leaf mosaic, mottling and malformation.
• Cassia corymbosa - mosaic, chlorotic spotting, flecking, vein yellowing, leaf malformation, yellow blotching and mottling.

Transmission

By vegetative propagation. Not transmitted by Myzus persicae. Virus transmitted by mechanical inoculation; transmitted by grafting; not transmitted by seed.

Geographical distribution

Spreads in the UK.

Experimental host range

Several (3-9) families susceptible. Experimentally infected plants mostly show chlorotic local lesions, systemic mottle or mosaic.

Diagnostically susceptible host species and symptoms

• Chenopodium amaranticolor, C. quinoa - chlorotic local lesions, systemic flecks and lines.
• Cassia occidentalis - local systemic mild mottle/mosaic; plants die.
• Nicotiana clevelandii - chlorotic local lesions, systemic mottle.
• N. tabacum cv. White Burley - faint chlorotic local lesions; not systemic.
• Phaseolus vulgaris cv. Prince - chlorotic local lesions/vein yellowing; systemic chlorotic flecks and vein yellowing.
• Pisum sativum cv. Monteith - systemic chlorotic mosaic and leaf malformation; plants die.
• Trifolium repens cv. White Clover - systemic vein necrosis.
• Vigna unguiculata ssp. sesquipedalis - necrotic local lesions; systemic necrotic spots and vein necrosis.

Diagnostically insusceptible host species

Brassica campestris ssp. pekinensis, Cassia obtusifolia, Cucumis sativus cv. Parisienne Pickling, Nicotiana glutinosa, N. rustica.

Maintenance and propagation hosts

Nicotiana clevelandii, Pisum sativum cv. Monteith (for purification).

Assay hosts (Local lesions or Whole plants)

Chenopodium quinoa (L).

Susceptible host species

• Cassia corymbosa
• Cassia occidentalis
• Cassia tora
• Chenopodium album
• Chenopodium amaranticolor
• Chenopodium foetidum
• Chenopodium murale
• Chenopodium quinoa
• Glycine max
• Nicotiana clevelandii
• Nicotiana megalosiphon
• Nicotiana tabacum
• Phaseolus vulgaris
• Pisum sativum
• Trifolium repens
• Vicia faba
• Vigna unguiculata
• Vigna unguiculata ssp. sesquipedalis

Insusceptible host species

• Brassica campestris ssp. pekinensis
• Cassia obtusifolia
• Cucumis sativus
• Glycine max
• Nicotiana debneyi
• Nicotiana glutinosa
• Nicotiana rustica
• Nicotiana sylvestris
• Pisum sativum
• Vigna unguiculata

Families containing susceptible hosts

• Chenopodiaceae (5/5)
• Leguminosae-Caesalpinioideae (3/4)
• Leguminosae-Papilionoideae (7/7)
• Solanaceae (3/7)

Families containing insusceptible hosts

• Cruciferae (1/1)
• Cucurbitaceae (1/1)
• Leguminosae-Caesalpinioideae (1/4)
• Leguminosae-Papilionoideae (3/7)
• Solanaceae (4/7)

Sources of host-range data

Ngamyeesoon (1989); Ngamyeesoon and Hicks (1988).

Physical and biochemical properties

Properties of particles in sap

TIP: 50-55 °C. LIV: less than 1 days. DEP: log₁₀ minus 4-5. Leaf sap contains few virions.

Purification method

Purification largely unsuccessful due to fragility of virions.

Particle morphology

Virions filamentous; not enveloped; usually flexuous; with no clear modal length; of 150-2168 nm; 10-12 nm wide. Axial canal obscure. Basic helix obscure.

Features of the genome

1-3 virus specified dsRNA species found in infected cells (major, also 8 minor). Size of largest virus specified dsRNA 13-15 kbp; 2nd largest 1.2-1.3 kbp; 3rd largest 0.4-0.5 kbp.

Cytopathology

Virions found in leaves, epidermis and veins.

Taxonomy and relationships

Possible Closterovirus

Best tests for diagnosis

Virion properties distinguish this virus from a carlavirus isolated from Cassia, and which does not infect Chenopodium amaranticolor, C. quinoa, Phaseolus vulgaris and Pisum sativum (Lin et al., 1979).

Comments and References

References

• Ngamyeesoon, N. (1989). Ph.D. Thesis, University of Bath, U.K. 343 pp.
• Ngamyeesoon, N. and Hicks, R.G.T. (1988). Acta Hort. 234: 45.

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.