Evaluation of reaction of watermelon cultivars to watermelon chlorotic stunt virus by agroinoculation with an infectious clone of the virus

Watermelon chlorotic stunt virus (WmCSV) is a bipartite begomovirus and one of the destructive watermelon viruses in the south and south-eastern Iran. WmCSV is responsible for huge losses of watermelon production in these regions. In this study, 11 commercial watermelon cultivars from the most current available cultivars were selected and used to evaluate their reaction against WmCSV by agroinoculation method with an infectious clone of the virus. Results showed that cultivar PS of Crimson Sweet watermelon, and Proseed, WLNOOL-201046 and Charlee cultivars of Charleston Gray watermelon are relatively less susceptible to WmCSV with infection rate of 24.4, 52.17, 67.74 and 74.07%, respectively, whereas watermelon plants of the rest of the cultivars were completely susceptible. In addition, four relatively resistant cultivars were differently reacted to WmCSV infection and among them, Proseed cultivar showed the mildest symptoms. The infectious construct is a rapid tool to evaluate the reaction of cultivars and can facilitate the identification of the resistant genetic sources against viral diseases.