Semi-field and surveillance data define the natural diapause timeline for Culex pipiens across the United States

Posted by Vector and Vector-borne Disease Committee
February 8, 2023

Field, E.N., Shepard, J.J., Clifton, M.E. et al. Semi-field and surveillance data define the natural diapause timeline for Culex pipiens across the United States. Commun Biol 5, 1300 (2022). https://doi.org/10.1038/s42003-022-04276-x 

Abstract:

Reproductive diapause serves as biological mechanism for many insects, including the mosquito Culex pipiens, to overwinter in temperate climates. While Cx. pipiens diapause has been well-studied in the laboratory, the timing and environmental signals that promote diapause under natural conditions are less understood. In this study, we examine laboratory, semi-field, and mosquito surveillance data to define the approximate timeline and seasonal conditions that contribute to Cx. pipiens diapause across the United States. While confirming integral roles of temperature and photoperiod in diapause induction, we also demonstrate the influence of latitude, elevation, and mosquito population genetics in shaping Cx. pipiens diapause incidence across the country. Coinciding with the cessation of WNV activity, these data can have important implications for mosquito control, where targeted efforts prior to diapause induction can decrease mosquito populations and WNV overwintering to reduce mosquito-borne disease incidence the following season.

Note: This article highlights the importance of the roles of both short day lengths as well as temperature in inducing diapause in Culex pipiens.  Comparisons were also made between the diapause timelines of Cx. pipiens in different geographical locations throughout the US and the influence of contributing variables such as latitude, elevation, and population genetics.