Pepino mosaic virus (PepMV) is a relatively new plant virus that has become a signifi cant agronomical problem in a relatively short period of time. It is a member of the genus Potexvirus within the family Flexiviridae and is readily mechanically transmissible. It is capable of infecting tomato (Solanum lycopersicum) and other Solaneceous host plants. Since its description in 1980 from pepino plants (Solanum muricatum) collected in 1974 in Peru, the virus remained unknown for a long time until it manifested itself in commercial tomato crops in Europe in 1999. Since then the virus has been reported worldwide and the disease it causes has become important in commercial tomato production. Since 1999, new strains of the virus have been described which diff er from the original pepino isolate. The fast spread of the virus and the appearance of mixed infections with the new strains may play an important role in the increase of the agricultural importance of this viral diseas