Fungus fights mites that harm honey bees
A new fungus strain could provide a chemical-free method for eradicating mites that kill honey bees, according to a study published this month in
A team led by Washington State University entomologists bred a strain of Metarhizium, a common fungus found in soils around the world, to work as a control agent against varroa mites. Unlike other strains of Metarhizium, the one created by the WSU research team can survive in the warm environments common in honey bee hives, which typically have a temperature of around 35 Celsius (or 95 F).
“We’ve known that metarhizium could kill mites, but it was expensive and didn’t last long because the fungi died in the hive heat,” said Steve Sheppard, professor in WSU’s Department of Entomology and corresponding author on the paper. “Our team used directed evolution to develop a strain that survives at the higher temperatures. Plus, Jennifer took fungal spores from dead mites, selecting for virulence against varroa.”