Several braconid parasitoid species have been released in Hawaii for control of fruit infesting tephritid pests. During the past ten years, though, concerns about possible nontarget effects by these parasitoids has almost halted new introductions. To address this problem, parasitoids used for biological control of frugivorous tephritids were examined for possible nontarget effects on flowerhead infesting tephritids. The first goal was to determine if flowerheads were attacked in the field by parasitoids previously released in Hawaii for tephritid fruit fly biological control. From June to August 2001, we collected and isolated 882 composite flower heads on the Hawaiian Island of Oahu. Both tephritid and argomyzid flies emerged from the flowerheads. Parasitoids from the flower heads were limited to one species of Pteromalidae and one eucoiline Figitidae, neither of which was previously released against frugivorous tephritids. Our second objective was to determine if Psyttalia concolor Silvestri, an opiine braconid proposed for released against medfly, would attack infested flowerheads in a choice test with pamakani galls. The parasitoid did not attack hosts in either the nontarget flowerheads or galls. These results suggest opiine parasitoids used in biocontrol of fruit infesting tephritids do not pose a threat to flowerhead tephritids.
Species 1: Hymenoptera Braconidae Psyttalia concolor
Keywords: Non-target effects, Fruit flies
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