Controlled and polygynous mating in the black soldier fly: advancing breeding programs through quantitative genetic designs

Abstract

In animal breeding programs, utilizing quantitative genetic designs such as the full-/half-sibling design is fundamental. A full-/half-sibling design demands that mating can be controlled, and individuals can be tracked for the construction of a pedigree. In nature, black soldier fly (Hermetia illucens L.) males are reported to gather in lekking groups to engage in competitive displays and courtship rituals before mating. This lekking behavior is described as crucial for establishing suitable conditions and achieving successful mating, and polygyny is therefore assumed to be rare. We show that when exposing a virgin male to a virgin female, they readily mate, demonstrating the ability to mate without prior lekking and that it is possible to mate selected pairs. Furthermore, we show that successful mating can be achieved between an individual male and at least four virgin females within a four-hour time span, and that nearly all matings result in live offspring. Our findings pave the way for moving H. illucens breeding programs beyond mass selection towards advanced selective breeding designs demanding controlled mating. Such designs enable selection for multiple traits simultaneously, are used to prevent inbreeding, and can drastically increase rates of selection responses compared to mass selection.