Oviposition deterrence and larvicidal activity of three formulations of piperidine repellent (AI3-37220) against field populations of Stegomyia albopicta

Two proprietary controlled-release (CR) formulations (CR55 and CR56) of 20% AI337220 (1-[3-cyclohexen-1-ylcarbonyl]-2-methylpiperidine) in an aqueous dispersion, and the same repellent formulated in water (W220), were compared with a repellent-free control for oviposition deterrent and larvicidal activity against natural populations of Stegomyia albopicta. A single application of each formulation (final concentration: 0.1%) prevented oviposition by St. albopicta for 4 wk, with highest deterrence (46%) observed for CR55 at 8 wk posttreatment. At the same application rate, each repellent formulation reduced larval activity in experimental containers by 100% through week 4 posttreatment and, for CR55, by 92-100% through week 8. In a municipal cemetery (Gainesville, Florida, USA), 1 application of CR55 or CR56 (final concentration: 0.1%) in concrete flower vases eliminated St. albopicta larvae for 10 wk. With formulation improvements to enhance efficacy at low repellent concentrations, AI3-37220 may have potential for use in the control of container-inhabiting mosquitoes.