Cucurbit yellow stunting disorder virus

First report of Cucurbit yellow stunting disorder virus in Arizona and possibly California (pending DNA confirmation)

Significance:
Cucurbit yellow stunting disorder virus (CYSDV) was detected for the first time in Arizona melon fields. Melons in Imperial Valley, California are also suspected of having the virus, however DNA testing is still underway. This whitefly transmitted virus causes yellowing of the older leaves and is closely related to Lettuce infectious yellows virus. CYSDV is native to the Middle East but was previously detected in west Texas where it caused reduced yields and quality. Arizona melon growers are experiencing similar reductions. (Katz, 2006)

Issues of Concern: Damage in certain Arizona melon production areas is widespread (Katz, 2006) and control of CYSDV can be difficult due to a lack of resistant cultivars and the ability of the vector to become resistant to insecticides (EPPO, 2005).

Hosts:At present, CYSDV appears to be exclusive to the Cucurbitaceae plant family. Lactuca sativa is considered an experimental host (EPPO, 2005).

Vector(s)/Dispersal:Bemisia tabaci (EPPO, 2005)

Detection Strategies
There are two groups of CYSDV isolates: one is composed of isolates from Spain, Lebanon, Jordan, Turkey, and North America; the other is from Saudi Arabia (EPPO, 2005).