Ceratopogonidae) to I-octen-3-ol and Three Plant- Derived Repellent Formulations in the Field

The potential attractant l-octen-3-ol and 3 potential repellents were assayed for activity for Culicoides sonorensis, the primary vector of bluetongue virus in North America. Collections using octenol were low, but numbers in suction traps were greater in the high-octenol treatment (11.5 mg/h) than in the low-octenol treatment (1.2 mg/h) or unbaited control for both sexes. Collections using high octenol, CO, (-1,000 ml/min), or both showed octenol alone to be significantly less attractive than either of the CO, treatments and that octenol did not act synergistically with this level of COr. A plant-derived (Meliaceae) extract with 4.5Vo of active ingredient (AI) (AglOOO), heptanone solvent, Lice free@ (24o Al from plant extracts in water), Mosi-guard with 5OVo Eucalyptus maculata v^r. citriodora Hook extract, and N,N-diethyl-m-toluamide (deet) were applied to polyester--cotton coarse mesh nets and deployed in conjunction with suction light traps plus COr. Collections in the trap with deet were 667o lower (P < 0.05) than the heptanone and 56Vo (P > 0.05) less than the untreated (negative) control. Relative to deet, collections in the traps with the lice repellent, Ag1000, and Mosi-guard were reduced by 15,34, and 39Vo, respectively (P > 0.05). The method has promise for field screening of potential repellents before on-animal testing.