Investigations of insecticide tolerance allele frequencies in Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae)

Homalodisca vitripennis(Germar) causes significant losses in wine industry earnings through the spread of Pierce’s disease and additional costs brought about by its population control. Increased use of pesticides application however has an undesirable effect of selecting for populations with insecticide tolerant traits that eventually render their use ineffective. To evaluate the levels of insecticide tolerance in wild populations of H. vitripennis, 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. Samples from reared colonies were subjected through bioassays by exposure to different concentrations of insecticides and monitoring insecticide dosage, exposure levels and mortality responses. Preliminary results indicate diversity in insecticide dose responses to all the four chemicals used; malathion, baygon, endosulfan and cypermethrine, with mortalities recorded from concentrations of 0.01µg/vial(Baygon) to 25µg/vial(malathion) for 100% mortality.