Celery mosaic virus (CeMV) is a plant pathogenic virus in the genus''

Potyvirus ''Potyvirus'' is a genus of positive-strand RNA viruses in the family ''Potyviridae''. Plants serve as natural hosts. The genus is named after member virus ''potato virus Y''. Potyviruses account for about thirty percent of the currently known ...

'' and the virus family ''

Potyviridae ''Potyviridae'' is a family of positive-strand RNA viruses that encompasses more than 30% of known plant viruses, many of which are of great agricultural significance. The family has 12 genera and 235 species, three of which are unassigned to ...

''. In

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

, mosaic diseases of

celery Celery (''Apium graveolens'') is a marshland plant in the family Apiaceae that has been cultivated as a vegetable since antiquity. Celery has a long fibrous stalk tapering into leaves. Depending on location and cultivar, either its stalks, ...

(''Apium graveolens'') were reported as early as 1922. After some time, it became clear that there were at least two different viruses causing mosaic diseases with similar symptoms in celery. These two viruses were first differentiated by host range. One of the viruses had a wide host range and was named ''Southern celery mosaic''. The second had a host range restricted to the family Umbelliferae (

Apiaceae Apiaceae or Umbelliferae is a family of mostly aromatic flowering plants named after the type genus '' Apium'' and commonly known as the celery, carrot or parsley family, or simply as umbellifers. It is the 16th-largest family of flowering plan ...

) and was called ''Western celery mosaic''. Continued research showed that the ''Southern mosaic virus'' was actually an isolate of ''

Cucumber mosaic virus ''Cucumber mosaic virus'' (CMV) is a plant pathogenic virus in the family ''Bromoviridae''. This virus has a worldwide distribution and a very wide host range, having the reputation of the widest host range of any known plant virus. It can be tra ...

'' and '' Western celery mosaic'' eventually became known simply as ''Celery mosaic virus''.

Symptoms and host range

Symptoms of celery mosaic virus include a distinct mottled pattern on the leaves, distorted leaf growth with exaggerated rosette formation. Some strains of celery mosaic virus cause a "crinkled" pattern to form on the leaves of the plant. Oftentimes, plants infected with celery mosaic virus early in their development do not produce usable crops. Plants infected by the virus late in their development may provide usable crops provided that the crops are harvested quickly after infection.

Celery Celery (''Apium graveolens'') is a marshland plant in the family Apiaceae that has been cultivated as a vegetable since antiquity. Celery has a long fibrous stalk tapering into leaves. Depending on location and cultivar, either its stalks, ...

is the most common host of this virus. As the name implies, this virus causes a mosaic or mottling in the leaves of celery. There can also be malformation of leaflets. In older leaves, chorotic/necrotic spots may occur and the plants can be stunted. In addition to celery, this virus has been identified in other important crops in the ''

'' including

carrot The carrot ('' Daucus carota'' subsp. ''sativus'') is a root vegetable, typically orange in color, though purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the wild carrot, ''Daucus carota'', na ...

s (''Daucus carota''),

coriander Coriander (;

(''Coriandrum sativum''),

parsley Parsley, or garden parsley (''Petroselinum crispum'') is a species of flowering plant in the family Apiaceae that is native to the central and eastern Mediterranean region (Sardinia, Lebanon, Israel, Cyprus, Turkey, southern Italy, Greece, ...

(''Petroselinum crispum''),

parsnip The parsnip ('' Pastinaca sativa'') is a root vegetable closely related to carrot and parsley, all belonging to the flowering plant family Apiaceae. It is a biennial plant usually grown as an annual. Its long taproot has cream-colored skin an ...

(''Pastinaca sativa''), and

dill Dill (''Anethum graveolens'') is an annual herb in the celery family Apiaceae. It is the only species in the genus ''Anethum''. Dill is grown widely in Eurasia, where its leaves and seeds are used as a herb or spice for flavouring food. Growth ...

(''Anethum graveolens''). It has also been identified in several weed species in the family

, including

poison hemlock ''Conium maculatum'', colloquially known as hemlock, poison hemlock or wild hemlock, is a highly poisonous biennial herbaceous flowering plant in the carrot family Apiaceae, native to Europe and North Africa. A hardy plant capable of living in ...

(''Conium maculatum''), mock bishopweed ('' Ptilimnium capillaceum'') and wild cherry ('' Apium leptophyllum''). There is some confusion in the literature as to whether CeMV can infect hosts in the family ''

Chenopodiaceae Amaranthaceae is a family of flowering plants commonly known as the amaranth family, in reference to its type genus '' Amaranthus''. It includes the former goosefoot family Chenopodiaceae and contains about 165 genera and 2,040 species, making i ...

''. In 2002, a paper reporting the results of a survey in Australia found three different but related potyviruses infecting species of the ''Apiaceae'' in Australia, CeMV, ''Carrot virus Y'' (CarVY), and '' Apium virus Y ''(ApVY). Both CarVY and ApVY have been shown to infect one or more species of ''Chenopodium''. The latter reference, reporting ApVY infecting celery in New Zealand, found the plants to be doubly infected with CeMV and ApVY and the authors suggested that CeMV “may mask the presence of ApVY”. It is possible that one or both of these viruses have been undetected in mixed infections with CeMV in some of the past studies. With sequence data now available for both CarVY and ApVY this ambiguity may be cleared up in time.

Geographic distribution

The geographic distribution of this virus is probably worldwide. In North America, besides California (USA), it has been reported in Florida and in Ontario, Canada. In Europe it has been reported in the UK, France, Germany, Italy, the Netherlands and in the former Czechoslovakia. In South America it has been identified in Argentina, Brazil, and Chile. It has also been identified in Japan, Australia and New Zealand.

Transmission and disease management

Celery mosaic, like most potyviruses, is non-persistently transmitted by

aphids Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

. This means that the aphid can pick up the virus on its stylet (its mouthparts) and transfer it quickly to the next plant it probes. The virus can also be transmitted mechanically by tools and machinery. At least 26 different aphid species are known to transmit the virus. There is no evidence of seed transmission. Because chemicals are not effective in treating plant viruses, management of celery mosaic virus focuses on reducing aphid population within colonies of plants. Recommendations for management of celery mosaic virus include planting resistant cultivars, spreading out crops, clearing weeds from crop fields, and treating crops with pesticides. Because celery mosaic virus also affects umbelliferous plants, removal of umbelliferous weeds, like wild celery and wild parsnip, helps to control aphid populations. Celery grown in fields that have been host free for 2–3 months show greatly reduced risk of exposure to CeMV. Many studies have shown reduced virus outbreaks and severity in fields treated with reflective

mulch A mulch is a layer of material applied to the surface of soil. Reasons for applying mulch include conservation of soil moisture, improving fertility and health of the soil, reducing weed growth and enhancing the visual appeal of the area. A mu ...

which can provide unappealing visual stimuli to infected aphids. Fields treated with this mulch experience reduced infection rates.

Genome

The complete genome of Celery Mosaic Virus was sequenced in 2011. It was found to be 9999 nucleotides in length, encoding for 3181 amino acids in a single large open reading frame, and sharing between 39 and 72% of its sequence identity with other members of the genus Potyvirus, and is most closely related to Apium virus Y. Together, CeMV, Apium virus Y, and Panax virus Y form a distinct clade.

References

External links

* ICTVdB - The Universal Virus Database
Celery mosaic virus
via Web Archive * Descriptions of Plant Viruses
Celery mosaic virus
* Plant Viruses Online – VIDE Database

{{DEFAULTSORT:Celery Mosaic Virus Viral plant pathogens and diseases Potyviruses Celery