COLUMBUS, Ohio -- A study at Ohio State University has shown that selective breeding helps honeybees develop resistance to tracheal mites, pests that beekeepers normally control with insecticide.
The research indicates that with a combination of selective breeding and other natural controls, beekeepers may maintain healthy hives without relying on chemical controls.
Before Ohio State began selectively breeding for mite resistance, about half of the bees at the university had tracheal mites. As of spring 1997, the number had dropped to nearly undetectable levels, without the use of chemicals.
The problem with treating bee hives with chemicals is that the honey could become contaminated, said Susan Cobey, apiarist at Ohio State. The mites eventually develop a resistance to the chemicals anyway. We are trying to develop more natural techniques for controlling tracheal mites that will be practical for commercial beekeepers.
Cobey explained that tracheal mites are but one of the problems facing honeybees in North America: cold winters, wet springs, and pesticides have all combined to lower the bee population in recent years. In fact, wild populations of bees in the United States are nearly extinct.
Beekeepers currently manage about 3 million colonies of honeybees in the United States, and they have suffered losses as well, although not as severe. Estimates of managed bee colony losses to mites vary from state to state.
In a recent issue of the American Bee Journal, Cobey explained how beekeepers could control tracheal mites effectively over the long term -- by breeding bees that carry the genetic traits that help them combat the mites.
Cobey said that such genetic resistance occurs naturally. Bees in Europe,
where scientists first discovered tracheal mites in the 1920s, have long
Contact: Susan Cobey
Ohio State University