Distribution and incidence of watermelon crinkle leaf-associated virus 1, watermelon crinkle leaf-associated virus 2, and other viruses in cucurbits in South Florida

A survey of cucurbits grown in South Florida was conducted from 2020-2022 for viruses. A total of 481 plant samples (470 cucurbit and 11 non-cucurbit) included watermelon, squash, cantaloupe, cucumber, zucchini, five weeds commonly found in cucurbit fields, cowpea, and two vegetable volunteer plants growing in a watermelon field. Samples were tested for cucurbit chlorotic yellows virus (CCYV), squash vein yellowing virus (SqVYV), papaya ringspot virus-W (PRSV-W), watermelon crinkle leaf-associated virus 1 (WCLaV-1), watermelon crinkle leaf-associated virus 2 (WCLaV-2), cucurbit yellow stunting disorder virus (CYSDV), and cucurbit leaf crumple virus (CuLCrV). All seven viruses were detected with WCLaV-1 as the predominant virus found in cucurbits, followed by CYSDV and WCLaV-2. The majority of samples were mixed infections containing two or more viruses. Host tissue testing found the peduncle was a good source for testing for all viruses. Host symptoms were variable on leaves for WCLaV-1 and WCLaV-2 and in mixed infections with the other five viruses. More studies are required to ascertain the role of WCLaV-1 and WCLaV-2 in mixed infections and their effect on plant health, fruit quality, and yield.