Poster Display
Plant-Insect Ecosystems
Jeanbaptiste Quirino
ACRPC
Gilbert, Arizona
Ethan Stahura
ACRPC
Mesa, Arizona
Earl Andress
USDA-APHIS
Phoenix, Arizona
Michael A. Garvey (he/him/his)
Supervisory Agriculturist (Asst. Lab. Dir.)
USDA
Chandler, Arizona
Bacillus thuringiensis (Bt) is a bacterium known for its capabilities as a natural biopesticide against insect pests. However, when trying to mass-rear insects for biological control or sterile insect technique it is detrimental and can have catastrophic consequences, potential crashing the whole insect colony. If not properly controlled, this pathogen can rapidly become prevalent and hard to remove. Bt spores are highly resistant to disinfectants as bacillus is among the most challenging bacteria to kill.
Disinfectants and the autoclave were tested to sterilize rearing containers. Colony counts, larvae infection, and moths yield were observed.
Results for disinfectants showed an increase in Bt (+ 150.34%) whereas the autoclave showed a decrease (- 99.35%). Disinfectants had 38.57% severe Bt infected larvae and a 56.21% moth yield whereas the autoclave had 18.31% severe Bt infected larvae and a 70.88% moth yield.
Using the autoclave against Bt spores were significantly more effective than using disinfectants. Identifying sterilization methods that are the most effective is essential in maintaining Bt prevalence at its lowest within the colony. Future research would involve key tools to sterilization components of a mass rearing facility such as application of germicidal ultraviolet radiation. Monitoring and reacting to pathogen presence is crucial to keep the colony healthy and reach the target number of insects produced.