Location: Weed and Insect Biology Research
Project Number: 3060-30500-001-011-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jun 1, 2026
End Date: May 31, 2027
Objective:
The honey bee is responsible for pollinating about a third of our food supply and in decline in part because of American Foulbrood, against which burning the entire hive is often the only solution. Paenibacillus larvae is the causative agent for this devastating disease. The formation of spores is the primary reason why it is exceedingly difficult to fight infection.
Our approach is to use ClO2 gas to sterilize the bee hive frames. A previous MS student showed that chlorine dioxide(ClO2) was effective at killing spores of P. larvae on small coupons of assorted materials that are relevant in a bee hive. We propose to up-scale the experiment to the use of quarter hive frames.
Approach:
For the production of the ClO2 gas, we will use the two-part dry system from Fruitgard media (ICA TriNova; Newnan, GA). Two quarter hive frames will be sterilized with ClO2 and inoculated with 100 µl of a spore solution of ~10E5 spores of P. larvae. Water spots will serve as negative control on both frames. This will be done on the wood part of the frames, the plastic part, and the wax part. One of these two frames will be sterilized again. Spores will be recovered with FLOQ swabs and resuspended in PBS. From this solution, we will produce serial dilution and plate onto MYPGP plates. Colonies will be counted after several days of incubation at 37oC. As a second method of detection, we will use the DNeasy PowerLyzer Microbial Kit from Qiagen and perform digital PCR at the Dr. Thomas Glass Biotech Innovation Core at NDSU.
In addition, we will determine the concentration of ClO2 in the container that the frames will be sterilized in. This will be done at different time points, samples will be taken and analyzed via HPLC and/or mass spectrophotometry at the USDA. The experiment will be repeated with frames inside the container to determine how much of the gas the frames may absorb. We will use the maximum concentration produced by the two-part system to sterilize the frames for the experiment.