| dc.description.abstract | In recent years, the black soldier fly, Hermetia illucens, (Diptera: Stratiomyidae) has been ranked high in sustainable agriculture due to its ability to transform organic waste into insect protein and compost. Numerous companies globally are implementing this concept, even though our understanding of this insect is still limited. This dissertation investigated how the insect larval host interacts with its associated bacteria when the host is starved as well, the actual production system for this insect at a large scale. By investigating the relationship of the bacteria community and the larval host during starvation, I determined a metabolically active microbial community shift in response to the larval host starvation. I also determined a decrease (P=0.0025) in microbial community diversity at the phylum level, and I identified six standout genera (Actinomyces, Microbacterium, Enterococcus, Sphingobacterium, Weissella, and Leucobacter) that had significantly different relative abundances between treatments. When investigating the microbial activities during the above-mentioned condition, I determined there were 103 microbial genes significantly different across treatments. These findings can lead to protein production optimization by manipulating the associated microbe in the feed substrate for the black soldier fly larvae to induce higher food intake.
Scale of study impacted life-history traits of the black soldier fly and its production. I determined results from the previous studies done on bench-top scale might not apply to the real world. Because of changing the rearing conditions, larval life-history traits exhibited significant differences in survivorship, biomass conversion rate, and larval sizes. The H. illucens larvae in the small container had 28.2% lower survivorship than in the large rearing tray (P<0.05), and they are 24.7% larger in size than in the large tray (P<0.05). However, the bioconversion rate in the large tray is 2.7% bigger than in the small containers (P<0.05).
Research in this dissertation identified few issues that might cause management troubles in the production system, such as density of larval inoculation in the rearing system, and the microbe associated with the food substrate that might cause variability in the production system, though more works are needed to be done in order to understand the mechanisms as well as to find solutions for production optimization. | en |
