Monday, December 11, 2006

Monitoring for insecticide resistance in the glassy-winged sharpshooter, Homalodisca coagulata (Say) in southeastern United States

Raphael Ndondo Abanja, and Lambert H. B. Kanga, Florida A&M University, Entomology, 1700 S Martin Luther King BLVD, Room 406 FAMU/Perry-Paige Bldg, Tallahassee, FL

Uncontrolled populations of the glassy-winged sharpshooter (GWSS), Homalodisca coagulata (Say) is currently of major concern in the wine industry and has already inflicted real losses in earnings through increased use of pesticides and other methods employed to reduce its populations. Increased pesticide application however has the undesirable effect of selecting for resistant populations of the insect, thereby rendering their use ineffective. To evaluate the levels of insecticide resistance in wild populations of the GWSS, we reared laboratory colonies from wild type collections across vineyards of North Florida on various plant species that included Vigna unguiculata, Hibiscus spp. and Halianthus spp.. The F1 generations of the laboratory reared samples were then subjected through biossays by exposing them to different concentrations of insecticide and monitoring insecticide dosage, exposure levels and mortality responses. Preliminary results indicate different levels of resistance to all the four insecticides, malathion, cabaryl, endosulfan and cypermethrine, with low motalities recorded at concentrations of 0.01g/vial for all the four chemicals and 100% motality for concentrations of 1.0g/vial for cypermethrin.

Species 1: Hemiptera Cicadellidae Homalodisca coagulata (glassy-winged sharpshooter)