Aedes albopictus (Diptera: Culicidae): a statistical model of the role of temperature, photoperiod, and geography in the induction of egg diapause.

Aedes albopictus (Skuse) lays eggs refractory to hatching in response to several environmental cues. The goal of this statistical treatment was to quantify the role and interaction of latitude and country of origin (Japan and the United States), photoperiod, rearing/holding temperature, and a newly identified element, elevation of the site of origin, with critical photoperiod (Cpp). We also describe the development of an equation relating the incidence of diapause to daylength, rearing/holding temperature, and latitude and elevation of the site of origin, an equation useful in the development of a simulation model of the population dynamics and distribution of Ae. albopictus in North America. The analysis indicated that elevation from 0 to 300 m is significantly correlated with Cpp. The results also corroborate earlier conclusions that, on the basis of a shallower geographical cline in photoperiodic response in the United States, North American strains of Ae. albopictus have a temperate origin in Asia and indicate that the rapid spread of this mosquito within the United States via the distribution of used tires resulted in founder populations that were only partially adapted in diapause response to local conditions.