Effects of photoperiod on population performance and sexually dimorphic responses in two major arbovirus mosquito vectors, Aedes albopictus and Aedes aegypti (Diptera: Culicidae)

Abstract

AbstractThe Asian tiger mosquito,Aedes albopictus(Skuse) and the yellow fever mosquito,Aedes aegypti(Linnaeus) are medically important species that vector several arboviruses. Globally, populations of both species experience (and are sensitive to) photoperiodic variations. The present study aims to test if photoperiod regimes affect the population performance ofAe. albopictusandAe. aegypti. Since mosquitoes have sex-specific strategies to maximize fitness, we also tested the hypothesis thatAe. albopictusandAe. aegyptiwould exhibit differences in the male and female response (sexually dimorphic response) to various photoperiod treatments. We reared cohorts of first instar larvae to adulthood in three photoperiod treatments: short day (10 h light), control (12 h light) and long day (14 h light). We measured and compared survival to adulthood, population growth, development time of males and females, and wing length across treatments. Although we detected no effects of photoperiod on the population performance of both species, we found evidence of a sexual dimorphic response to photoperiod inAe. albopictus, but not inAe. aegypti, withAe. albopictusfemales being more sensitive to variations in photoperiod. The observed differences between sexes ofAe. albopictusare consistent with sex-specific developmental constraints. The absence of a sexually dimorphic response to photoperiod inAe. aegyptican be attributed to different strategies evolved in this species to prepare for unfavourable conditions associated with shorter day length. We discuss the ecological and medical implications of our findings.