Progress and challenges in managing watermelon vine decline caused by whitefly-transmitted Squash Vein Yellowing Virus (SqVYV)

Abstract

Watermelon vine decline (WVD) is an emerging threat to watermelon production in southwest and west-central Florida. Losses in 2004-2005 due to WVD were estimated to be more than 60 million US dollars. The disease is caused by Squash vein yellowing virus (SqVYV, family: Potyviridae, genus: Ipomovirus) and is transmitted by whiteflies (Bemisia tabaci). SqVYV is a close relative of, but distinct from, another cucurbit-infecting ipomovirus, Cucumber vein yellowing virus (CVYV), that has been reported from most countries in the Mediterranean Basin since it was first described in Israel in the 1960s. Symptoms of WVD typically include a sudden decline and death of vines at or just prior to harvest. Fruit symptoms include internal flesh degradation and necrosis of the fruit rind. So far, only cucurbits have been confirmed as hosts for SqVYV, and striking symptoms of vine decline in agricultural production have been observed only on watermelon. Balsam-apple (Momordica charantia), a cucurbit weed that is widely dis...