FACTORS INFLUENCING HOST CHOICE OF THE HONEY-BEE PARASITE VARROA-JACOBSONI OUD

Reproducing Varroa jacobsoni obtained from brood cells of Apis mellife ra L. with 13-16 day old bees (pupae) and Varroa mites kept on adult b ees for at least 8 days were simultaneously tested for their choice in three host types. Comparisons were made of attractiveness of Varroa j acobsoni to nurse bees, pollen foragers as to larvae from nearly cappe d brood cells. Host choices were observed in Petri dishes and in an Y- shaped olfactometer. Varroa jacobsoni obtained from capped brood cells showed a stronger preference for nurse bees in Petri dish simultaneou s choice tests with pollen foragers or larvae than did mites which wer e previously kept on adult bees. In olfactometer simultaneous choice t ests, the two mite test groups showed no clear difference in preferenc es for bees of different ages. The preference of Varroa jacobsoni for bees of different ages is therefore not only influenced by host factor s but also by intrinsic factors in female mites that depend on the mit e's reproductive stage.