Résumé
Wolbachia infection influence the immature competition of Aedes ablopictus. In low competitive conditions, infected females emerge in high number than expected. In high competitive conditions, infected individuals (females and males) emerge in low number than expected.
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Wolbachia enhances immature survivorship of
A. albopictus female under low competition. ►
Wolbachia reduces immature survivorship of
A. albopictus female under high competition. ►
Wolbachia reduces immature survivorship of
A. albopictus male under low competition.
Bacterial endosymbionts induce various effects on hosts and can dramatically impact host fitness and development. An example is provided by obligate, maternally-inherited
Wolbachia, which infect a broad range of invertebrates.
Wolbachia are capable of altering host reproduction, thereby promoting infection spread.
Wolbachia also pose direct physiological costs and benefits to hosts, complicating their categorization as parasites or mutualists. This study examines for an effect of
Wolbachia infection in intra-specific larval competition by
Aedes albopictus mosquitoes, with the goal of examining for an impact of
Wolbachia infection in mixed populations. Similar to prior work examining for an influence of
Wolbachia infection on the fitness of
A. albopictus in adults, the results presented here support the hypothesized impact of
Wolbachia across all life stages, including immatures. The differential competitiveness of infected larvae detected in our experiments indicates that
Wolbachia infected
A. albopictus females are less competitive relative to uninfected females when competing under highly competitive conditions. In contrast, under low competitive pressures, infected females experience higher survivorship. Thus,
Wolbachia infection shifts from parasitism to mutualism as a function of developmental conditions. Results are discussed in relation to the invasion and persistence of
Wolbachia in
A. albopictus populations.
The results are important to the evolution of stable
Wolbachia symbioses, including
Wolbachia invasion of an uninfected population. The resulting infection dynamics that occur in an infected population are discussed.