Melon severe mosaic virus: a new Tospovirus of cucurbits in Mexico
During the 2007 growing season, several melon plants (Cucumis melo) showed leaf mosaic and deformation, as well as fruit splitting, in the state of Guerrero in Mexico. Electron microscopic examination strongly suggested the presence of a virus belonging to the Bunyaviridae family, and possibly to the Tospovirus genus. Studies of the biological, serological and molecular properties of the virus, together with phylogenetic studies, confirmed that it was a new and distinct species of Tospovirus. This new species was tentatively called Melon severe mosaic virus (MeSMV). In February 2008, a preliminary survey of cucurbit crops was carried out across Mexico. In total, 147 cucurbit plants (Cucumis melo, Cucurbita pepo, Cucumis sativus, Citrullus lanatus) showing virus-like disease symptoms were collected and tested with RT-PCR for the presence of MeSMV. The new virus was found in 66% of the symptomatic plants which had been collected from Cucumis melo (melon), Cucurbita pepo (courgette), Cucumis sativus (cucumber), Citrullus lanatus (watermelon) crops. The virus was also detected on cucurbit samples from various states (Campeche, Chiapas, Guerrero, Jalisco, Mexico, Michoacán, Puebla, Sinaloa) suggesting that it was already widespread and established in the country. For the moment, no insect vectors have been identified, but it was observed that Frankliniella occidentalis was present on MeSMV-infected plants.
Sources
Ciuffo M, Kurowski C, Vivoda E, Copes B, Masenga V, Falk BW, Turina M (2009) A new Tospovirus sp. in cucurbit crops in Mexico. Plant Disease 93(5), 467-474.