Cucurbit aphid-borne yellows

Symptoms and Signs. Cucurbit aphid-borne yellows luteovirus causes a general yellowing of the older leaves, which become thick and leathery. The major veins of these leaves remain green. Growth and yield of infected plants may be reduced.
Comments. This virus is persistent: it is acquired and transmitted in hours and the aphid vector may retain the virus for its entire life. Vector specificity is high; the cotton (melon) aphid, Aphis gossypii, transmits the virus very efficiently while the green peach aphid, Myzus persicae, is a poor vector. The source of the virus is unknown, possibly wild cucurbits.