Association of Varroa destructor females in multiply infested cells of the honey bee Apis mellifera

The genetic diversity of Varroa destructor (Anderson and Trueman) is limited outside its natural range due to population bottlenecks and its propensity to inbreed. In light of the arms race between V. destructor and its honey bee (Apis mellifera L.) host, any mechanism enhancing population admixture of the mite may be favored. One way that admixture can occur is when two genetically dissimilar mites co-invade a brood cell, with the progeny of the foundresses admixing. We determined the relatedness of 393 pairs of V. destructor foundresses, each pair collected from a single bee brood cell (n = five colonies). We used six microsatellites to identify the genotypes of mites co-invading a cell and calculated the frequency of pairs with different or the same genotypes. We found no deviation from random co-invasion, but the frequency of cells infested by mites with different genotypes was high. This rate of recombination, coupled with a high transmission rate of mites, homogenized the allelic pool of mites within the apiary. This article is protected by copyright. All rights reserved