EVALUATION OF 4 SEED-DERIVED OILS AS CONTROLS FOR ACARAPIS-WOODI (ACARI, TARSONEMIDAE) IN COLONIES OF APIS-MELLIFERA (HYMENOPTERA, APIDAE)

Four seed-derived oils were evaluated in field trials as control agents for the parasitic tracheal mite, Acarapis woodi (Rennie), in colonies of the honey bee, Apis mellifera (L.). Seventy-one honey bee colonies infested with the tracheal mite were each assigned to 1 of 4 treatment groups or to a control group. Treatments were peanut, soybean, sunflower, or canola oil, delivered as patties after blending with confectioner sugar (2 parts sugar/1 part oil [wt:wt]). All 5 groups had similar mite prevalence values (proportion of infested bees) and parasite load scores (a measure of the number of mites per bee) before initiating treatment. Each colony received five 500-g patties delivered approximately every 14 d starting on 16 September 1992 and continuing until 1 December 1992. Mite prevalence values, parasite load scores, and colony weight gains (an indicator of honey production) were measured the following spring. Average mite prevalence values obtained on 4 and 5 May 1993 in the treated groups ranged from 0.015 to 0.027, compared with 0.094 in the control group. The mite prevalence value in each treatment group was less than the mite prevalence value in the control group. Similar differences were observed for parasite load scores. Differences in colony weight gains among the 5 groups were not significant.