|NATWICK, ERIC - University Of California - Cooperative Extension Service|
|BATUMAN, OZGUR - University Of California|
|Wintermantel, William - Bill|
|TIAN, TONGYAN - California Department Of Food And Agriculture|
|McCreight, James - Jim|
|VALENZUELA, CONNIE - California Department Of Agriculture|
|GILBERTSON, ROBERT - University Of California|
Submitted to: Electronic Publication
Publication Type: Research Notes
Publication Acceptance Date: 12/9/2014
Publication Date: 12/9/2014
Citation: Natwick, E.T., Batuman, O., Wintermantel, W.M., Tian, T., McCreight, J.D., Valenzuela, C., Gilbertson, R.L. 2014. A new and potentially damaging whitefly-transmitted virus of cucurbits was found this fall 2014 in Imperial County, CA. Pest-O-Gram. December 9, 2014: 1–3.
Technical Abstract: A new virus that appears to be related to but distinct from Squash vein yellowing virus (SqVYV), a Bemisia tabaci-transmitted ipomovirus (family Potyviridae) that occurs in Florida was found in fall 2014 in Imperial County, CA infecting pumpkin and melon plants and exhibiting symptoms of stunting and leaf yellowing, crumpling and downward leaf cupping. Sequence comparisons performed with the cylindrical inclusion (CI) and coat protein (CP) genes of this California ipomovirus revealed the closest identity, 83% and 99%, respectively, with the CI and CP genes of SqVYV. Pumpkin and squash plants inoculated with sap prepared from leaves of three pumpkin plants in which the California ipomovirus was detected by RT-PCR, developed mild mottling, vein clearing and yellowing symptoms that are similar to those reported for SqVYV. The SqVYV was identified infecting squash in Florida in 2003. It was subsequently shown to cause watermelon vine decline (WVD), which is similar in appearance to a bacterial wilt type of disease. WVD has caused substantial losses to watermelon production in Florida. Therefore, the finding of a very similar whitefly-transmitted ipomovirus in California is a major concern to cucurbit growers. Hopefully, the prompt identification of the virus together with the destruction of all known infected plants will prevent the establishment of this ipomovirus in Imperial County. Hosts of SqVYV have been reported to be limited to crops and weeds in the cucurbit family, Cucurbitaceae, including melon (cantaloupe and honeydew), cucumber, pumpkin, summer and winter squashes, watermelon, cucurbits grown as ornamental vines (such as Luffa) and a few common weeds, such as buffalo gourd.