Antennal olfactory responses in the black soldier fly Hermetia illucens

Abstract

The Black Soldier Fly (BSF) is considered as the "crown jewel" of the insect feed industry and circular economy, significantly contributing to the 2030 Sustainable Development Goals by reducing carbon dioxide emissions and enabling circular management of organic waste, animal manure, and plant residues. Despite their industrial importance, limited knowledge about adult BSF biology has hindered optimal mass production. In this context, the present paper aims to explore the olfactory capabilities of both male and female BSF in response to various odorants commonly associated with organic decomposition in substrates suitable for mate encounters and egg laying. This will be achieved by performing electroantennographic recordings and scanning electron microscopy (SEM) observations on the antennal sensilla. Our results demonstrate for the first time the supposed olfactory capabilities of BSF antennae and present a first dataset of substances emitted by decaying organic matter detected by both male and female flies. Additionally, the current EAG recordings allowed comparisons with molecular data previously obtained through in silico and in vitro methods, highlighting the need for caution and strongly supporting a multidisciplinary approach as the best tool for investigating insect chemical ecology. These findings advance our understanding of BSF chemical ecology, which is crucial for effective reproduction and could significantly optimize global breeding systems.

Keywords: Antennal sensilla; BSF; Chemical ecology; Electroantennography (EAG); Organic decomposition volatiles; Ultrastructure (SEM).