fly larvae were not exposed naked to parasit- oids but were mixed with wheat diet substrate before packing them in the stinging unit (Wong & Ramadan 1992). In our tests, besides wheat diet, we likewise utilized pureed papaya as a substrate. Both substrates were used merely for purposes of confirming whether odor stimuli other than those that may be associated with the treatment larvae would influence the choice made by the female parasitoids. Wheat millfeed (Arm strong, B.C. Canada), a bulking material routinely used in B. dorsalis larval diet formulation, was mixed with pureed papaya or wheat diet substrate in equal parts (by weight) to make mixture drier. Otherwise, female parasitoids would shy away from the wet surface of the stinging unit (Wong & Ramadan, 1992).