Bacteria regulate attraction and colonization of a resource by the black soldier fly (Diptera: Stratiomyidae)

While traditional approaches in community ecology aim to explore the interactions between multicellular organisms, advances in technology and biological understanding have allowed researchers to investigate inter-kingdom interactions. Microbes have been recognized as an important factor in the selection of oviposition sites by a number fly species. The black soldier fly, Hermetia illucens (L.), (Diptera: Stratiomyidae) is found worldwide and reproduces in a variety of decomposing materials. Consequently, this fly is important in green technologies for recycling agricultural waste. In this study we aimed to determine the role microbes, from black soldier fly eggs and from known dipteran and coleopteran competitors, play in black soldier fly oviposition behavior. We hypothesized bacteria from black soldier fly eggs will be attractive to conspecific flies, and those from competitors will repel or have a lower level of attraction. A secondary objective was to compare traditional microbiological and molecular approaches for identifying the microbes targeted in this study. Bacterial identification was accomplished with a 1200 bp length segment of 16s rDNA isolated using universal primers and verified with phenotype indices. We demonstrate that microbes on eggs are an important factor regulating oviposition behavior. Some bacteria from competitors at high concentrations were less attractive to oviposition, while a mixture of bacteria species from black soldier flies, as well as some individual components of the mixture were attractive at high concentrations. A better understanding of the role bacteria play in this behavior will expand our understanding of arthropod succession patterns in ephemeral resources and enhance sustainable agriculture.