Most common viral diseases of cucurbits in Illinois are cucumber mosaic (Cucumber mosaic virus), papaya ringspot (Papaya ringspot virus), squash mosaic (Squash mosaic virus), watermelon mosaic (Watermelon mosaic virus), and zucchini yellow mosaic (Zucchini yellow mosaic virus). Depends on the time of infection, viral diseases could cause up to 100% yield losses in cucurbit fields in Illinois.