Effects of soil on larval mosquito development and adult oviposition behavior of Culex pipiens quinquefasciatus (Diptera: Culicidae)

Water quality is known to affect development and survival of larval mosquitoes, which subsequently affects mosquito-borne pathogen transmission. Although many studies have demonstrated effects of water properties on mosquito development, few studies have investigated the link between soil properties, water, and mosquitoes. Given that many mosquito species develop in water on the ground, this study explored the effects of soil substrate on various life history parameters of Culex pipiens quinquefasciatus mosquitoes (Diptera: Culicidae). Cx. quinquefasciatus larvae were reared in water combined with different soil substrates (sand, silt, or clay loams) at increasing soil to water volume ratios (0.1%, 1%, 10%, 25%, 50%), with and without the addition of organic material (fish food). Blood fed mosquitoes were offered soil-water cups to investigate soil effects on oviposition preference. Without added food, larval development differed significantly between soil type and amount, with only mosquitoes in clay soils reaching pupation (ANOVA, P < 0.001). Adding food to the cups significantly reduced the effect of soil type on survival time (ANOVA, P = 0.422), but not development time (P < 0.001) or pupation (P = 0.046). Adult female mosquitoes had a strong preference for soil with higher mineral content, selecting clay soils 70% of the time (ANOVA, P < 0.001). This study suggests soil composition plays an important role in larval mosquito survival and development. Future studies may explore additional soil types to better understand how soil affects mosquitoes, improving our understanding of the landscape characteristics that support mosquito populations and pathogen prevalence.