Occurrence of two genotypes of Varroa jacobsoni oud. in North America

Abstract

Both the Russian and Japanese genotypes of Varroa jacobsoni were present in the United States and Canada. Only the Russian genotype was found in Mexico. Our results suggest that North America, and especially the United States has had more than one introduction of Varroa jacobsoni. Differences in virulence among strains of V. jacobsoni may be the basis for reports of regional variation in honey bee resistance to Varroa. Thus, further studies on the interaction between Varroa and honey bee genotypes are needed to fully resolve the issue.