Viruses of cucurbits in Panama.
The main areas of field-grown cucurbit production in Panama were surveyed for the occurrence and distribution of viruses in the growing seasons of 2006 and 2008. Notably, in 2006 only Melon necrotic spot virus (MNSV) was detected, while Papaya ringspot virus (PRSV) was the most frequent in 2008 in terms of number of fields and samples analysed, followed by Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV) and MNSV. Cucumber mosaic virus (CMV), Squash mosaic virus (SqMV), Cucumber green mottle mosaic virus (CGMMV), Tomato spotted wilt virus (TSWV), Cucumber leaf spot virus (CLSV), Cucurbit yellow stunting disorder virus (CYSDV), Cucurbit aphid-borne yellows virus (CABYV), Beet pseudo-yellows virus (BPYV), Beet yellows virus (BYV), and Cucumber vein yellowing virus (CVYV) were not detected. Single and double (PRSV+WMV; PRSV+ZYMV; ZYMV+MNSV) infections were detected in 60% and 40% of the samples tested, respectively. The occurrence and distribution of each virus varied according to the province and cucurbit species.