The resistance of Varroa jacobsoni Oud. to acaricides

Abstract

A serious problem in the control of the mite Varroa jacobsoni Oudemans is the selection of acaricide-resistant strains. Increased tolerance of this mite to several active substances (acrinathrin, amitraz, bromopropylate, chlordimeform, coumaphos, flumethrin, fluvalinate) was determined with laboratory assays or presumed as the most likely explanation of decreased field efficacy. Resistance to fluvalinate in Italy and later in other countries caused heavy damage to beekeeping. Early detection of the presence of resistant Varroa mites was crucial to reduce losses. Regarding resistance management tactics, 'moderation tactics' seem to be more suitable than 'high dose tactics' to delay the selection of resistant Varroa strains.