Gel Could Stop Two Mites With One Treatment
By Jill Lee
November 24, 1997
Domestic honey bees can be protected from both tracheal and varroa
mites--two major pests of this crucial insect--with an application of formic
acid mixed with a food-grade gelling agent.
Scientists with USDAs
Agricultural Research Service say the
gel formulation could smooth the path to U.S. registration of formic acid to
combat both mites. Thats because the gel would reduce a beekeepers
contact with the acid.
The ARS researchers filed a patent on the technology last week. They say
beekeepers could alternate the formic acid gel treatment with the
industrys standard varroa mite-fighter, fluvalinate. This would help slow
the varroa mites progress toward fluvalinate resistance in this country.
U.S. beekeepers get nervous when they read about varroa mites in Italy and
France developing resistance to fluvalinate, because it is currently the only
U.S.-registered pesticide against varroa mites. Menthol is the approved product
for treatment of tracheal mites.
Formic acid has proven effective outside the U.S. against both varroa and
tracheal mites. But liquid formic acid evaporates quickly and must be
re-applied four to five times per season.
The ARS scientists say sealing the formic acid and gel in a plastic bag
would give beekeepers a product requiring less handling. The bag could be
sliced open inside the hive, allowing the formic acid to evaporate and leave
behind only a harmless residue. In field tests, the experimental product killed
up to 84 percent of the varroa mites and 100 percent of the tracheal mites, an
Worker bees gather nectar for honey and pollinate plants during the last
part of their life cycle. Mites not only kill the bees at this critical time,
but also quickly spread throughout other hives. This can have effects beyond
destroying a beekeepers expensive investment. California, for example,
uses half a million bee colonies annually to pollinate its almond crop alone.
Scientific contact: Mark Feldlaufer ,
Laboratory, USDA, ARS, Beltsville, Md. Phone: (301) 504-8205; fax: (301)
504-8736, e-mail: email@example.com