Serological identification of virus in watermelon production fields in the tocantins state

Abstract

Watermelon (Citrullus lanatus) cultivated in almost all tropical and subtropical regions of the world, has its largest output in China, and then, according to FAO data, Turkey, Iran and Brazil, being one of the main crops cultivated in State of Tocantins, Brazil. In this work was investigated the occurrence and distribution of the watermelon viruses, totaling 752 samples taken in a stratified experimental design in four representative regions of production: Gurupi (150), Lagoa da Confusao (232), Formoso do Araguaia (265) and Porto Nacional (105). The sampling and collecting the leaves of plants with the presence of symptoms were performed once a week during the entire cultivation cycle. As a result, were observed by Dot-ELISA method, different types of viruses, such as Papaya ringspot W (PRSV-W), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV) (potyvirus), Cucumber mosaic virus ( CMV) (Cucumovirus) and Zucchini lethal chlorosis virus (ZLCV) (Tospovirus). Of these, PRSV-W was predominant (22%), followed by WMV (15%), ZLCV (11%), CMV (5%) and ZYMV (4%). Mixed infections with PRSV-W + WMV and PRSV-W + ZLCV were also observed around 20% frequency (expressed with symptoms differently from a single infection). The results provide important support for the program management viruses.