Plant Viruses Online   

Descriptions and Lists from the VIDE Database

Echinochloa ragged stunt oryzavirus

Index

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

Data collated by C.C. Chen, 1991.

Nomenclature

Acronym

ERSV

ICTV decimal code

60.0.9.0.002

Host range and symptoms

Natural host range and symptoms

Symptoms persist. Symptoms severe stunting, darker green leaves, serrated margins and veinal swellings.
• Echinochloa crus-galli var. oryzicola, Setaria italica, Triticum aestivum - tillering, severe dwarfing, malformation of leaves with serrated margins and veinal swellings. Plants appear greener and fail to head, or show a delay in heading time leading to empty grains.

Transmission

Transmitted by a vector; an insect; Sogatella vibix, S. longifurcifera; Delphacidae. Not transmitted by Nephotettix cincticeps, N. nigropictus, Nilaparvata lugens, Laodelphax striatellus, Sogatella furcifera, Recilia dorsalis. Transmitted in a persistent manner. Virus retained when the vector moults; multiplies in the vector; not transmitted congenitally to the progeny of the vector; transmitted by mechanical inoculation; not transmitted by grafting; not transmitted by contact between plants; not transmitted by seed; not transmitted by pollen.

Geographical distribution

Spreads in Taiwan.

Experimental host range

Few (<3) families susceptible. Experimentally infected plants mostly show severe dwarfing, leaf malformation, ragged leaf, vein-swelling on abaxial surface of leaf sheaths, and a dark green plant colour.

Diagnostically susceptible host species and symptoms

• Alopecurus aequalis, Echinochloa crus-galli var. formosensis, Eleusine coracana, Lolium multiflorum, Oryza sativa, Setaria italica, Triticum aestivum - excessive tillering, dwarfing and production of malformed leaves with serrated margins and veinal swellings. Leaves darker green.
• Imperata cylindrica var. major - leaf yellowing and small vein swellings.
• Zea mays - milder symptoms and recovery after 2-3 weeks.

Diagnostically insusceptible host species

Cynodon dactylon, Eleusine indica, Hordeum vulgare, Leersia hexandra, Sorghum bicolor.

Maintenance and propagation hosts

Echinochloa crus-galli, Lolium multiflorum, Setaria italica.

Assay hosts (Local lesions or Whole plants)

Alopecurus aequalis (W), Echinochloa crus-galli (W), Eleusine coracana (W), Lolium multiflorum (W), Setaria italica (W).

Susceptible host species

• Alopecurus aequalis
• Echinochloa crus-galli
• Echinochloa crus-galli var. formosensis
• Echinochloa crus-galli var. oryzicola
• Eleusine coracana
• Imperata cylindrica
• Imperata cylindrica var. major
• Lolium multiflorum
• Oryza sativa
• Setaria italica
• Triticum aestivum
• Zea mays

Insusceptible host species

• Cynodon dactylon
• Echinochloa colona
• Eleusine indica
• Hordeum vulgare
• Leersia hexandra
• Sorghum bicolor

Families containing susceptible hosts

• Gramineae (12/18)

Families containing insusceptible hosts

• Gramineae (6/18)

Sources of host-range data

Chen et al. (1986).

Physical and biochemical properties

Properties of particles in sap

TIP: 70-80 °C. LIV: 3 days. DEP: log₁₀ minus 6-7. Leaf sap contains few virions. Electron microscopy: fix with glutaraldehyde.

Purification method

Chen et al. (1988).

Particle morphology

Virions isometric; not enveloped; 80 nm in diameter; angular in profile; with a conspicuous capsomere arrangement.

Physical properties

Two sedimenting components in purified preparations. A₂₆₀/A₂₈₀ ratio 1.8.

Biochemical properties

Genome consists of RNA; double-stranded; linear. Total genome size 26.64 kb (pairs). Genome of 10 parts (named S1-10); largest (or only) genome part the largest 3.85 kb (pairs); the 2nd largest 3.82 kb (pairs); the 3rd largest 3.8 kb (pairs); the 4th largest 3.7 kb (pairs); the 5th largest 2.7 kb (pairs); the 6th largest and other parts 2.6 kb (pairs; also 1.95, 1.85, 1.20 and 1.17 kb pairs). Genomic nucleic acid isolated by Chen et al. (1989).

Features of proteins

Virion protein(s) six (4 major, 2 minor); M_r of the largest 127000 (major). M_r of 2nd largest 123000 (major). M_r of 3rd largest 103000 (minor). M_r of 4th largest 63000 (major). M_r of 5th largest 50000 (minor). M_r of 6th largest and smaller, 34000 (major). Method of preparation: Chen et al. (1989).

Cytopathology

Virions found in leaves and phloem. Inclusions present in infected cells; are viroplasms; they contain virions.

Taxonomy and relationships

Oryzavirus: Reoviridae

Best tests for diagnosis

ELISA.

Comments and References

References

• Chen, C.C. (1985). Ph.D. Thesis, 150 pp. Grad. Inst. Pl. Path., Nat. Chung-Hsing Univ.
• Chen, C.C., Chen, M.J. and Chiu, R.J. (1986). Pl. Prot. Bull. (Taiwan) 28: 371.
• Chen, C.C., Chen, M.J., Chiu, R.J. and Hsu, H.T. (1989). Phytopathology 79 ;235.
• Chen, C.C., Chiu, R.J., Chen, M.J., Wang, Y.S. and Ko, W.H. (1980). Pl. Prot. Bull. (Taiwan) 22: 425.
• Chen, C.C., Hsu, Y.H., Chen, M.J. and Chiu, R.J. (1989). Intervirology 30: 278.
• Chen, C.C., Hsu, Y.H., Liu, M.C., Chen, M.J. and Chiu, R.J. (1988). Pl. Prot. Bull. (Taiwan) 30: 420.

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.