A long-term solution to the problems of parasitic mites and honey bee pathogens is the development of resistant stocks of bees. Several traits associated with varroa mite resistance are heritable (that is, available for selection) (Camazine, 1986; Camazine and Morse, 1988; DeJong, 1996; Harbo, 1992, 1993; Harbo and Harris, 1999a,b; Harbo and Hoopingarner, 1995; Harbo et al., 1997; Moritz, 1985; Moritz and Hanel, 1984; Rinderer et al., 2003). Similarly, tracheal mite resistance is a heritable trait (Gary et al., 1990; Page and Gary, 1990). A varroa-resistant stock of honey bees was developed at the U.S. Department of Agriculture (USDA) Agricultural Research Service (ARS) honey bee research laboratory in Baton Rouge, Louisiana (Harbo and Harris, 1999a), and is available commercially as SMR (suppressing mite reproduction) or SMART stock.
Related efforts also have focused on identifying honey bee populations with a long history of exposure to V. destructor as a potential source of resistant stock (Rinderer et al., 1999, 2001, 2003). ARS began to import bees from the Primorsky region in far-eastern Russia beginning in the early 1990s (Rinderer et al., 2005). The Russian bees were quarantined on an island off the coast of Louisiana, and they have been subject to further selection. The Russian bees exhibit a high degree of varroa mite resistance (Rinderer et al., 2003, and references therein), and they are now available commercially.
Resistance to American foulbrood and other bee pathogens was shown to be heritable in the 1930s (Park, 1936). Although other traits contribute to foulbrood resistance (Spivak and Gilliam, 1998a,b), the principal mechanism is hygienic behavior (Rothenbuhler, 1964). Stocks that exhibit hygienic behavior have been developed at least three times since the 1930s (Park et al., 1937, 1939; Rothenbuhler, 1964; Spivak and Reuter, 2001). Hygienic behavior also could operate in mite resistance (Boecking et al., 2000; Harbo and Harris, 2005; Spivak and Rueter, 2001), and the University of Minnesota has developed hygienic stocks that are available commercially.
Another challenge to the bee industry is the synthesis of results from federal and academic research into sustainable commercial queen-and-package operations. There are well-developed methods for quantifying resistance to mites and pathogens (Harbo and Harris, 1999a; Harbo et al., 1997; Spivak and Downey, 1998; Spivak and Gilliam, 1998a,b) and for breeding and maintaining resistant stocks (Harris et al., 2002; Page and Laidlaw, 1982a,b; Page et al., 1983, 1985). Perusal of trade journals reveals beekeepers’ interest in mite-resistant stocks of bees and the low availability of such stock: Several suppliers advertise Russian, SMR, or hygienic bee stocks, but there are no data on the number or quality of queens available. It is not clear why resistant stocks have not yet been widely adopted (Sheppard, 2006), but it is possible that the impediments include the difficulty of maintaining inbred