Safeguarding bee colonies from future disease worries
DOCTOR Emily Remnant has combined her interest in viruses with her fascination with bees to begin a study into breeding virus-resistant bees.
After receiving the Minister for Agriculture Award in addition to the AgriFutures Australia sponsored 2017 Science and Innovation Award for Young People in Agriculture Award, Dr Remnant has spent the past 12 months investigating immunisation of honey bees against viruses spread by the varroa mite.
“The aim of my research was to improve honey bee health by developing and enabling a novel method to increase honey bee resistance to viruses using a natural bacterial symbiont, wolbachia,” Dr Remnant said.
“During my PhD I worked in the same institute as a group who was using wolbachia in mosquitoes to stop the spread of dengue fever.
“So I thought, ‘well, it’s not known what the bacteria does in bees so I think we should test it’.”
Dr Remnant said the research was still in its early stages.
“The bacteria lives inside cells, so you can’t just feed it to bees and see what it does. You have to inject it into bees when the cells are still forming, so we tried injecting eggs. All the trials I did injecting into the eggs were unsuccessful.
“I then tried injecting queen bees, into their ovaries, which looked more promising.
“The survival rate was higher and most of the queens were positive with wolbachia after the injection.
“Eight per cent contained wolbachia in the ovaries. It’s a low percentage but it’s still better than zero.”
Dr Remnant said she used a micro injection to inject the bees, which involved a capillary needle connected to air pressure.
“We take the wolbachia out of a donor insect, in this case a fly egg, and then push it out of the capillary into the bee,” she said.
Dr Remnant said if her research was successful it would provide a new mechanism to prevent viral infection in bees.
“Infection from the varroa mite causes quite a lot of problems for beekeepers around the world. Beekeepers in the US report about 30 per cent of colony losses in recent years,” she said.
“They normally treat for varroa with chemicals and I think the mites now are getting resistant to the chemicals.
“So I think if we focus on another branch, which is the viruses, it gives people another option for preventing colony loss.
“It’s not an issue in Australia yet, but if we got the varroa mites, it would be good to have a virus-resistant type of bees.”
Dr Remnant said she hoped to have more information about the success of the wolbachia infections by the end of the year.
“Next spring I’ll repeat those experiments by injecting into queens,” she said.
“We’re investigating ways to get queens to lay eggs in the lab, which is not as easy as it seems.
“Then we’ll aim to test those offspring for virus resistance.”
If successful, it would still be a few years before field trials could take place.
“This is all lab-based research. We would need a lot more research before we’re able to use it in the field,” Dr Remnant said.
“There could be negative effects so I’d like to test for all that before we do field trials. It will be a few years away yet, but bit by bit we’ll get there.”