Varroa mite-resistant bee breeding could be the key to resisting the deadly pest

Bee breeder Corinne Jordan, who runs Bee Genetics in Brisbane, says a new pheromone spray she's trialling - developed in the US - may be a "ground breaking" solution to prevent a "catastrophic collapse" of honey bee colonies.

She believes the intervention approach, which could help breed resistance to Varroa, is a lower-cost alternative to the current approach, which involves eradicating infected hives in key zones of NSW.

Varroa has been found in much of Asia, Europe, the US, South America and New Zealand, but in June 2022, the industry's worst fears were realised when Varroa was detected in Newcastle.

While it has been contained, some in the industry believe an interstate spread is inevitable, putting at risk billions of dollars worth of agriculture that relies on pollination.

There is no known predator to Varroa and breeding for resistance has been problematic.

However, University of North Carolina Greensboro scientist Dr Kaira Wagoner has synthesised an odour into a spray which, when applied to brood - eggs, larvae and pupae found in the cells of combs - harmlessly simulates a Varroa mite infestation.

When the odour is detected by bees, they respond to it by removing the infested brood, breaking the lifecycle of the Varroa and stops them from reproducing.

It's understood commercialisation could happen by autumn 2024 Australian time.

EXCITED by the research, Brisbane bee breeder Corinne Jordan reached out to Dr Wagoner late last year and imported the spray.

She then partnered with Plan Bee lead researcher and University of Sydney researcher Dr Nadine Chapman to test the spray's efficacy and to demonstrate if breeding for Varroa resistance in Australia is possible.

"This is the only truly sustainable long-term method of combating this destructive pest," Ms Jordan said.

Ms Jordan has tested it on her established breeding population, which comprises about 130 hives of pedigree honeybees with commercially desirable traits as a base to breed from.

She's also been finding other bee breeders to work with so that they can identify more stock that responds well to this test and then they can swap stock and breed and, and start making selection efforts.

Dr Chapman said the spray was promising.

"These tests are the only way that you could start breeding for resistance without actually having Varroa," Dr Chapman said.

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"This is just one that's been developed, but it's the closest to being commercialised."

However, funding is short as the industry struggles to recover from droughts, bush fires, floods and COVID-19 in back-to-back succession and the team needs public and corporate help to raise enough money to progress this project.

The budget for the first year to cover all costs is $250,000 - even with a commitment of resources and labour by the breeder and researcher.

Ms Jordan said a large part of the budget would go to testing multiple locations across the eastern states of Australia to locate the 2-4 per cent of honeybee colonies that express natural Varroa resistance along with the genetic testing required.

She has spent between $70,000 and $100,000 a year on breeding over the past decade, and while she has made an income from her work, the past few years have been tough.

"I'm somewhere out of pocket for my breeding efforts to date of between $700,000 and $1 million to bring bees up to the level that they currently are," she said.

"I really love bees and I love breeding bees. It's more than just a job for me. So I thought, this is something I could give back to Australia.

"I'm quite happy to sit here and protect my own population of bees. But I believe that this can be done. And it's a worthwhile project. And we need to do it."

Ms Jordan has now launched a campaign on crowdfunding websites.

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