SARE Research Synopsis
Our goal was to breed honey bees, Apis mellifera, resistant to diseases and parasitic mites to reduce the amount of antibiotics and pesticides used in bee colonies, and to ensure that our breeding methods and stock are accessible to beekeepers everywhere. We have bred a line of bees for hygienic behavior called the "MN Hygienic line." Hygienic behavior, the ability of bees to detect and remove diseased and mite-parasitized brood from the nest, can be selectively bred into any line or race of honey bees. Our tests of the MN Hygienic line in commercial apiaries demonstrated that they have good resistance to American foulbrood (a highly contagious and deadly bacterial disease of bee larvae) and chalkbrood (a less serious fungal disease of bee larvae). The hygienic line is partially resistant to the devastating mite, Varroa destructor.
Since 2001, we have been incorporating another trait into the MN Hygienic line called "Suppression of Mite Reproduction" or SMR. We also have been investigating the mechanism for the SMR trait to determine how bees can reduce mite reproductive success. Our results demonstrated that bees bred for SMR are both hygienic and have some yet unknown property associated with their brood that reduces the number of viable offspring the mites produce. Combining the SMR trait into the hygienic line, therefore, helped increase the degree of hygienic behavior in our line, and added another factor that helps suppress mite reproduction. Field trials in commercial apiaries have demonstrated that the Hygienic/SMR cross significantly reduces mite loads in colonies relative to the pure Hygienic line and unselected lines of bees.
We are developing a web-based course called "Healthy Bees" on sustainable methods of controlling diseases and mite pests of honey bees. The main emphasis will be on promoting the use of resistant bee stocks as the foundation for integrated pest management strategies. This will be the only such course available online to beekeepers, and is a crucial link between our research and its successful implementation.