Cucurbit leaf crumple virus is a begomovirus that was first reported in squash in Florida in 2006. It hit watermelon growers around Southwest Florida especially hard this past spring. Identification Cucurbit leaf crumple virus (CuLCrV) usually starts in small patches in the field with new leaves showing yellowing. The yellowing pattern is unique and in early stages of infection appears between the veins. As the disease progresses, the yellowing of the leaves will spread to the leaf margin. A tell-tale symptom of CuLCrV infection is crumpling of the leaves. Eventually, leaves develop unusual twisting combined with thickening, crumpling, and yellowing. New leaves on runners can be severely infected with crumpling, which is readily noticeable. Unlike squash, which is severely damaged, watermelon plants may seem to recover from infection only for symptoms to rebound. On yellow squash and zucchini, symptoms include thickened and distorted leaves, which
Source: Take Caution to Curb Cucurbit Leaf Crumple Virus | Growing Produce
