Multi-omics comparison of two emerging storage pests (Necrobia rufipes and Tribolium castaneum) of dried black soldier fly larvae product.

The black soldier fly (BSF) larvae is a rich and promising source of alternative protein that continues to increasingly gain global traction as a functional ingredient for sustainable livestock and fish production. The key setback to postharvest processing of stored BSF larvae (BSFL) products is the significant damage caused by two notable storage pests (Tribolium castaneum and Necrobia rufipes). Here, we present a comparative analysis of the complete mitochondrial genomes and gut microbiome profiles of T. castaneum and N. rufipes. The study mitogenomes were similar in size and structure to other coleopteran mitogenomes. The gut microbiome profiles of the two pests showed a high abundance of bacteria in the Proteobacteria and Firmicutes phyla. However, T. castaneum had 78% more phyla represented within its microbiome than N. rufipes. The most abundant genera in T. castaneum were Staphylococcus and Streptococcus, while in N. rufipes, the dominant genera were Klebsiella and Synechococcus. We also identified the presence of potentially clinically harmful microbial genera (Stenotrophomonas maltophilia) in the gut of T. castaneum and N. rufipes in relatively high abundance. These results provide insight into potential harmful associations in the gut of the storage pest, picked from contaminated, poorly processed BSFL products.