White clover mosaic virus (WClMV) is a plant pathogenic virus in the genus ''

Potexvirus ''Potexvirus'' is a genus of pathogenic viruses in the order ''Tymovirales'', in the family ''Alphaflexiviridae''. Plants serve as natural hosts. There are 48 species in this genus, three of which are assigned to a subgenus. Diseases associated ...

'' and the family ''

Alphaflexiviridae ''Alphaflexiviridae'' is a family of viruses in the order ''Tymovirales''. Plants and fungi serve as natural hosts. There are 65 species in this family, assigned to six genera. Diseases associated with this family include: mosaic and ringspot sy ...

''. WClMV is a filamentous, flexuous rod, 480 nm in length and 13 nm wide. The virus is a monopartite strand of positive-sense, single-stranded RNA surrounded by a capsid made from a single viral encoded protein. The genome has been completely sequenced and is 5845 nucleotides long. It is transmitted by mechanical inoculation, contact between plants and sometimes by seed (6% in ''

Trifolium pratense ''Trifolium pratense'', the red clover, is a herbaceous species of flowering plant in the bean family Fabaceae, native to Europe, Western Asia, and northwest Africa, but planted and naturalized in many other regions. Description Red clove ...

''). No insect vector is known.

Host range and geographic distribution

Its major host is clover (''

Trifolium Clover or trefoil are common names for plants of the genus ''Trifolium'' (from Latin ''tres'' 'three' + ''folium'' 'leaf'), consisting of about 300 species of flowering plants in the legume or pea family Fabaceae originating in Europe. The genus h ...

'' spp). It was first reported in ''

Trifolium repens ''Trifolium repens'', the white clover, is a herbaceous perennial plant in the bean family Fabaceae (otherwise known as Leguminosae). It is native to Europe, including the British Isles,Clapham, A.R., Tutin, T.G. and Warburg., E.F. 1968. ''Excursio ...

'' in 1935. In the western United States and south western Canada it had been found in clover in a mixed infection with another potexvirus,

Clover yellow mosaic virus ''Clover yellow mosaic virus'' (ClYMV) is a plant pathogenic virus in the genus ''Potexvirus'' and the virus family ''Alphaflexiviridae''. Its flexous rod-shaped particles measure about 539 nm in length. Like other members of the Potexvi ...

. It is also known to infect peas (''

Pisum sativum The pea is most commonly the small spherical seed or the seed-pod of the flowering plant species ''Pisum sativum''. Each pod contains several peas, which can be green or yellow. Botanically, pea pods are fruit, since they contain seeds and d ...

''), faba beans (''

Vicia faba ''Vicia faba'', commonly known as the broad bean, fava bean, or faba bean, is a species of vetch, a flowering plant in the pea and bean family Fabaceae. It is widely cultivated as a crop for human consumption, and also as a cover crop. Variet ...

''), green beans (''

Phaseolus vulgaris ''Phaseolus vulgaris'', the common bean, is a herbaceous annual plant grown worldwide for its edible dry seeds or green, unripe pods. Its leaf is also occasionally used as a vegetable and the straw as fodder. Its botanical classification, alo ...

''),

cowpea The cowpea (''Vigna unguiculata'') is an annual herbaceous legume from the genus ''Vigna''. Its tolerance for sandy soil and low rainfall have made it an important crop in the semiarid regions across Africa and Asia. It requires very few input ...

(''Vigna unguiculata''), cucumbers (''

Cucumis sativus Cucumber (''Cucumis sativus'') is a widely-cultivated creeping vine plant in the Cucurbitaceae family that bears usually cylindrical fruits, which are used as culinary vegetables.Cucurbita ''Cucurbita'' (Latin for gourd) is a genus of herbaceous fruits in the gourd family, Cucurbitaceae (also known as ''cucurbits'' or ''cucurbi''), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and ...

pepo ''), and

tomato The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word ...

es (''Lycopersicon esculentum''). This virus is believed to be distributed in temperate regions worldwide.

Diagnosis

Potexviruses make banded inclusions made up of layers of parallel virus particles. These inclusions can be seen in the light microscope in leaf strips of infected plant tissue stained with Azure A or Orange-Green stains. The banded inclusions produced by WClMV are disrupted by the process of staining for inclusions. Those of ClYMV are not and thus inclusions can be used to distinguish these two potexviruses. Antiserum and sequence data are also available for the diagnosis of this virus.

References

External links

ICTVdB - The Universal Virus Database: ''White clover mosaic virus''

Descriptions of Plant Viruses

{{DEFAULTSORT:White Clover Mosaic Virus Potexviruses Viral plant pathogens and diseases