Pepino mosaic virus
(PepMV)

Pepino mosaic virus ,

,
- classification: Potexvirus, Flexiviridae


PepMV was introduced fairly recently in Europe , initially in the Netherlands in 1998. In this country, about forty outbreaks have been identified in greenhouse tomato crops. This virus then quickly spread to Great Britain, Belgium, Germany, and Austria. It has also been manifested in Spain (regions of Murcia, Almeria, and the Canary Islands), Denmark, Finland, Sweden, Estonia, and Italy. Three cases were detected in France in 2000 and 2001. This virus now affects Morocco and North America (several states in the United States and Canada), where it was observed from 2001. In the space of 2 years, this virus has therefore been disseminated on several continents.

This virus, which is transmitted rapidly by contact to a large number of plants, is not without effects on yields. Depending on the country, yield losses varying from 5 to 15% have been reported. In Spain, they were sometimes higher, of the order of 40%. A particularly aggressive strain would have had the same effects in Canada. To illustrate the infectious nature of this virus, remember that PepMV can infect at least 70% of tomato plants in a greenhouse, in about 6 weeks.


PepMV was detected for the first time in Peru in 1974, in crops of pepino ( Solanum muricatum ), an edible fruit called “melon-pear”. This species is traditionally cultivated in the Andes where its fruits are eaten fresh or in salads.

Several strains of this virus have been described on tomatoes around the world, in particular in the United States (US1 and US2), in Canada and in Europe (EU). These strains exhibited symptoms, aggressiveness and nucleotide sequences different from the original Peruvian strain (PE). More recently, three new strains have been isolated: two in Chile (CH1 and CH2) and one in Poland (PK). It should be noted by way of example that several of these strains (mainly EU, PE and US2) have been demonstrated in Spain, sometimes in mixed infections. In addition, the US1 strain has been found in the Canary Islands. On the North American continent, several major genotypes are also isolated: EU, US1, US2 and CH2. These observations tend to prove that the introduction of PepMV, in several countries at least, could have been carried out in several stages.

Finally, very recent molecular biology studies have made it possible for the moment to reduce their number of PeMV strains to five: PE, EU, US1 (same as CH1), US2 and CH2 (origin common to PK).

Virions are filamentous, unwrapped, and often flexuous, with a modal length of 508 x 11 nm.