|Kousik, Chandrasekar - Shaker|
Submitted to: American Phytopathology Society
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2007
Publication Date: 7/28/2007
Citation: Roberts, P., Stansly, P., Adkins, S.T., Bruton, B.D., Muchovej, R., Kousik, C.S. 2007. Management of watermelon vine decline in Florida. American Phytopathology Society.
Technical Abstract: Squash vein yellowing virus (SqVYV), the causal agent of watermelon vine decline (WVD) in Florida, is vectored by the silverleaf whitefly Bemisia tabaci (Biotype “B”). Watermelon plants mechanically inoculated at different growth stages from transplant to fruit formation with SqVYV developed WVD symptoms. Field studies were conducted in the spring and fall 2006 seasons to confirm the role of this ipomovirus in WVD and to develop management strategies through control of the vector. Watermelon in field plots grown adjacent to virus-infected squash also developed symptoms typical of WVD including fruit rot. Watermelon plants grown in screened cages that prevented whitefly infestation remained asymptomatic. SqVYV was detected in plants showing WVD symptoms but not in plants grown in screened cages. Insecticide applications of imidacloprid at transplanting and followed by weekly applications of pymetrozine did not significantly control whiteflies or WVD in the spring. However, in the fall trial, insecticide applications reduced whitefly numbers and WVD incidence and severity on treated plants compared with non-treated plants. Many watermelon growers are now using insecticides to manage whiteflies for control of WVD.