Plant Viruses Online   

Descriptions and Lists from the VIDE Database

Lettuce speckles mottle umbravirus

Index

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

Data collated by A.A. Brunt, 1992.

Nomenclature

Acronym

LSMV

ICTV decimal code

78.0.1.0.005

Host range and symptoms

Natural host range and symptoms

Symptoms vary seasonally.
• Beta vulgaris, Lactuca sativa, Spinacia oleracea - in mixed infections, the virus enhances the symptoms induced by beet western yellows luteovirus; the outer leaves of infected plants, especially those of lettuce, develop numerous angular chlorotic spots to produce the so-called speckles disease. Symptoms of the complex become less conspicuous as ambient temperatures rise.

Transmission

Transmitted by a vector; an insect; Acyrthosiphon (Aulacorthum) solani, Brevicoryne brassicae, Myzus persicae; Aphididae. Principal natural vector(s): Myzus persicae. Transmitted in a persistent manner. Virus requires, for vector transmission, a helper virus (beet western yellows luteovirus); transmitted by mechanical inoculation.

Geographical distribution

Spreads in the USA (California).

Experimental host range

Several (3-9) families susceptible.

Diagnostically susceptible host species and symptoms

• Beta vulgaris, Spinacia oleracea, Nicotiana glutinosa, Physalis floridana - no conspicuous systemic infection.
• Chenopodium quinoa - local lesions.
• Nicotiana clevelandii - faint interveinal chlorotic spotting of systemically infected leaves (especially under cool shady conditions).

Diagnostically insusceptible host species

Beta macrocarpa, Chenopodium amaranticolor, Datura stramonium, Nicotiana tabacum, Petunia × hybrida.

Maintenance and propagation hosts

Lactuca sativa, Nicotiana clevelandii.

Assay hosts (Local lesions or Whole plants)

Chenopodium quinoa (L), Nicotiana clevelandii (W).

Susceptible host species

• Beta vulgaris
• Brassica campestris ssp. napus
• Capsella bursa-pastoris
• Chenopodium capitatum
• Chenopodium murale
• Chenopodium quinoa
• Hyoscyamus niger
• Lactuca sativa
• Nicotiana clevelandii
• Nicotiana glutinosa
• Nicotiana glutinosa × N. clevelandii
• Physalis floridana
• Spinacia oleracea

Insusceptible host species

• Apium graveolens
• Beta macrocarpa
• Brassica campestris ssp. pekinensis
• Brassica juncea
• Chenopodium amaranticolor
• Cichorium endiva
• Conium maculatum
• Coriandrum sativum
• Datura stramonium
• Daucus carota
• Gomphrena globosa
• Lycopersicon esculentum
• Nicandra physalodes
• Nicotiana tabacum
• Petunia × hybrida
• Raphanus sativus
• Sonchus oleraceus

Families containing susceptible hosts

• Chenopodiaceae (5/7)
• Compositae (1/3)
• Cruciferae (2/5)
• Solanaceae (5/10)

Families containing insusceptible hosts

• Amaranthaceae (1/1)
• Chenopodiaceae (2/7)
• Compositae (2/3)
• Cruciferae (3/5)
• Solanaceae (5/10)
• Umbelliferae (4/4)

Comments on host-range

The host range of the virus is wider when viruliferous aphids are used to infect plants.

Sources of host-range data

Falk et al. (1979).

Physical and biochemical properties

Properties of particles in sap

LIV: 2 days (but twice as long in sap from plants also infected with beet yellows luteovirus).

Biochemical properties

Genome consists of RNA; single-stranded.

Taxonomy and relationships

Umbravirus

Comments and References

General comments

The virus probably lacks a functional coat protein and, in mixed infections, is probably encapsidated in that of beet western yellow luteovirus (its helper virus). It thus resembles carrot mottle, groundnut rosette, tobacco mottle and tobacco yellow vein viruses.

References

• Falk, B.W., Morris, T.J. and Duffus, J.E. (1978). Proc. Am. Phytopath. Soc. 5: 97.
• Falk, B.W., Duffus, J.E. and Morris, T.J. (1977). Phytopathology 69: 612.

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.