Incidence and genetic diversity of cucurbit viruses in Spain

[EN] Several viral diseases affect cucurbits, with different economic effects depending on the region and the year. However, there are not recent studies on the incidence of specific viruses. During the 2018 summer season, surveys were carried out in open field melon (Cucumis melo), squash (Cucurbita spp.) and watermelon (Citrullus lanatus) crops in most of the main producer areas under commercial (AGL2017-85563-C2 1R and 2R) and organic farming (PROMETEO/2017/078). Samples from plants with virus-like symptoms were analyzed by RT-PCR/PCR with specific primers, hybridization and/or ELISA, to detect Cucumber mosaic virus (CMV), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV), Moroccan watermelon mosaic virus (MWMV), Cucurbit yellow stunting disorder virus (CYSDV), Cucurbit chlorotic yellows virus (CCYV), Cucumber green mottle mosaic virus (CGMMV) and Tomato leaf curl New Delhi virus (ToLCNDV). Samples from fields in Murcia (south-eastern Spain), Castilla-La Mancha (central Spain) and Comunidad Valenciana (eastern Spain) were analyzed. At least one of these viruses was detected in approximately 80% of the samples. WMV was the most frequently detected in samples of the three crops. ZYMV, CMV, CYSDV and ToLCNDV were present with lower incidence, mainly identified in mixed infections with WMV.