COMPARATIVE RESISTANCE OF HONEY-BEES FROM A CLOSED POPULATION TO INFESTATION BY TRACHEAL MITES

The susceptibility of honey bees, Apis mellifera L., to infestation by the tracheal mite, Acarapis woodi (Rennie) was investigated in the 10th generations of 12 families from a closed population. Newly emerged worker bees, less than 18 h old, were marked and introduced into infested host colonies. After 14 days, the introduced bees were removed and preserved in alcohol for later dissection. The number of adult mites and larvae in the tracheae were determined. There were highly significant differences between families in the proportion of bees infested and in the numbers of mites in the infested bees. There were also differences in infestation among the host colonies. The seven families originating from the "south" were more resistant than the five from the "north". These two groups of bees also differed in a number of morphometric and behavioral characteristics (Szabo and Lefkovitch, 1988). The results suggest that selection of honey bees for tracheal mite resistance is feasible and that resistance may be associated with morphometric, behavioral and/or physiological characteristics.