Influence of larval aquatic habitat on the growth and development of Aedes aegypti mosquitoes

2013 student Victoria Knight worked with Professor Michael Strand and graduate students Kerri Coon and Kevin Vogel to investigate the effect of larval habitat on mosquito gut microbial communities.

Abstract  Mosquitoes host diverse bacterial communities that vary depending on many factors, including environment. The composition of bacteria present in the gut of adult mosquitoes is determined by the microbial community present in their larval aquatic habitat. Previous work indicates that the presence of bacteria in the larval aquatic environment is required for normal mosquito development. However, the degree to which larval habitat influences mosquito fitness is not well understood. Water samples were collected from natural breeding habitats around Athens, GA. Aedes aegypti larvae were reared in these water samples in the lab and larval development time, pupation rate, and wing length were used as proxies for fitness of emerging adult mosquitoes. Statistical analyses identified water source as a significant factor affecting larval development and wing length in adults. Filter sterilizing water samples resulted in no larval development, which was rescued by the addition of bacteria. Our results show that adult fitness varies with respect to larval aquatic environment, and that these differences may be explained by variation in the microbial communities present in different locations. This study supports an essential role for bacteria in larval growth and development, and suggests that differences in microbial communities may alter aquatic habitat quality and mosquito production in the field.