Abstract 【Aim】 This study aims to compare the synergism of 12 essential oils such as wintergreen oil to solid mosquito repellent in the bioassay of solid mosquito coil against Culex pipiens pallens, so as to provide a theoretical basis for the development and application of solid mosquito coil. 【Methods】 With the 3-5 day-old adults of Cx. pipiens pallens as the test insects, the synergistic effects of 12 essential oils including wintergreen oil, octagonal leaf oil, sassafras oil, camphor oil, citronella oil, litseacubeba oil, white camphor oil, lemon grass oil, peppermint oil, star anise oil, linaloe wood oil and lavender oil on allethrin in solid mosquito coil were determined using closed cylinder. Mixtures of essential oils with obvious synergistic effects screened above were made, the best mixture was screened using closed cylinder and the 5.8 m3 cabin, and its quality was tested. 【Results】 The results showed that five essential oils including wintergreen oil, linaloe wood oil, sassafras oil, white camphor oil and camphor oil had good synergistic effects on allethrin, with the synergistic ratios of 1.292-1.364, and the mixture of wintergreen oil and camphor oil (1∶1) had an obvious synergistic effect on allethrin. After selection of the solvent and emulsifier, the formula of synergists was determined as 30%-84% plant extracts, 10%-53.5% solvent and 6.5% emulsifier (NP-2), and the most economic formula of synergists was 30% wintergreen oil+30% camphor oil+3.35% ethyl acetate+30.15% butyl acetate＋6.5% NP-2. 【Conclusion】 The formulated synergist (30% wintergreen oil+30% camphor oil+3.35% ethyl acetate+30.15% butyl acetate＋6.5% NP-2）has an obvious effect on allyl permethrin in solid mosquito coil with a promising future of commercialization.
ZHANG Jie,LIU Hui,YANG Xiao-Wei et al. Screening of plant-derived synergistic agents for mosquito coil based on the bioefficacy against Culex pipiens pallens (Diptera: Culicidae)[J]. ACTA ENTOMOLOGICA SINICA, 2018, 61(1): 94-102.