ARS researchers have found a new virus playing hide and seek with the melon industry. In 2023, unusual symptoms of infection were observed in melon and watermelon plants from Arizona and California. ARS scientists in Salinas sampled infected plants and used gene sequencing technology to identify the culprit as watermelon chlorotic stunt virus (WmCSV).
This virus is transmitted by whiteflies and can cause significant yield loss — particularly in watermelon —but it also infects all types of cucurbit (melon, pumpkin, squash and cucumber) crops. WmCSV joins an existing virus complex causing yield impacts for production of melon and watermelon in the southwestern United States. This is the first time WmCSV has been identified in cucurbit plants in the Western Hemisphere. As a result, the cucurbit industry was notified of the threat posed by this virus, and they are taking efforts to keep it from being transported to other regions of the United States. — Story contributed by the USDA Ag Research Service