A new mutation in the octopamine receptor associated with amitraz resistance in Varroa destructor.

Background: The acaricide amitraz is now used intensively in many regions to control the honey bee parasite, Varroa destructor, because of the reduced efficacy of pyrethroids and coumaphos caused by resistance evolution. The continued application of amitraz in recent years exerts a very high selection pressure on mites, favouring the evolution of resistance to this acaricide. Mutations N87S and Y215H in the β2-adrenergic-like octopamine receptor (Octβ2R), target site of amitraz, have been already associated with resistance to amitraz in France and the USA, respectively.