Detection of fluvalinate resistance in Varroa destructor in Spanish apiaries

SummaryA laboratory assay developed by Milani (1995) was used to assess the susceptibility to the acaricide fluvalinate in 10 populations of Varroa destructor Anderson and Trueman from apiaries in Aragón (northeastern Spain). We assayed mites at the diagnostic concentration (200mg/kg) predicted to kill all susceptible mites. In some populations, LC50 values were obtained. Some mites were resistant to fluvalinate, which is the first reported case of fluvalinate resistance in Varroa destructor in Spain. Thus, it is inadvisable to base mite control strategies on chemical treatment alone. There is urgent need to expand and implement more biorational strategies in the fight against V. destructor.