(Surrey) While pesticides, pathogens and the effects of climate change are jeopardizing bees and their role as pollinators for global agriculture, another killer remains little known to the general public: the parasitic mite Varroa.
Posted at 2:33 p.m.
Chemistry professor Erika Plettner and her team of researchers at Simon Fraser University in British Columbia are testing a chemical compound that appears to kill mites without harming bees, in hopes it may one day be widely available as a treatment for infested hives.
Varroa mites kill bees by puncturing their cuticle, or exoskeleton, creating a wound that won’t heal, said PD Plettner.
This leaves a doorway for disease and weakens the bees’ immune system, she said in an interview at the researchers’ experimental apiary.
“That’s what ultimately knocks down (the bees) when they overwinter,” she said.
She and her team are testing the safety and efficacy of a compound identified in her lab a few years ago that appears to paralyze and then kill mites. Researchers don’t yet understand exactly how the product works. “We don’t know the mite protein that the compound binds to, or the collection of proteins. We know that the paralysis usually involves the nervous system of the mite,” said the professor.
His team recently secured funding from Genome British Columbia, a non-profit organization, to work with researchers at the University of British Columbia to study how the substance affects wartworms.
So far, the chemical compound shows promise as a potential treatment alongside five or six others currently available, according to PD Plettner.
It’s important to rotate different treatments from year to year, she warned, as the mites are starting to show resistance to existing products.
Varroa originated in Asia, but spread to Afro-European bee populations about 100 years ago, according to the professor. “In terms of evolution time, it’s relatively short. And that’s why our bees are so affected by this, because […] from an evolutionary point of view, they have not had the chance to develop, by selection, natural defenses. »
Efforts are underway to find bees that are more naturally resistant to mites, said PD Plettner, noting that one of his own hives had been mite-free this summer, while the neighboring hive was “overflowing” with parasites.
“Once in a while you get a fairly mite-resistant hive, and that’s a subject of very intensive research and beekeeping effort. »
It will take a few more years to commercialize the compound, making it available as a treatment, according to his estimates.
Researchers have yet to understand how it works and demonstrate that it is safe for bees, beekeepers and the surrounding environment.
Mitigating varroa infestations is particularly important given the range of environmental pressures bees face, explained PD Plettner, citing climate change and pesticides in particular.