Chemoecological Study on the Semiochemicals Controlling Behavior of Tephritid Fruit Flies

雌雄果蝇对植物产生的特定化学物质表现出很强的亲和力。桔小实蝇(Bactrocera Dorsalis)对甲基丁香酚和一些相关的苯丙烷类化合物有很强的吸引力，常被用作花香或植物成分的物质所吸引。雄性捕食者选择性地将这些化合物转化为吸引雌性的信息素，并将其储存在直肠腺中。有气味的雄性比无气味的雄性交配成功，表明获得化合物(S)在交配成功方面具有优势。桔小实蝇对苯丙烷类化合物的嗜药作用似乎是在性别选择的背景下进化出来的，特别是雌性更喜欢带有植物化学物质的雄性气味。另一方面，α-Copaene是一种有效吸引地中海果蝇雄性的引诱剂，在各种植物的精油中被发现是次要成分，包括它的主要寄主，如橙子、番石榴和芒果。尽管有如此特殊的吸引力，雄性果蝇从不以完整的化合物为食，因此α-杜松烯的生物学意义尚不清楚。在实验室试验中，用()-α-Copaene处理的塑料叶片模型人工诱导了头状蜡虫的类LEK行为。研究还发现，在短程生物测定中，α-Copaene会影响处女雌性，引发“假性”求偶行为。交配只发生在用α-Copaene处理的人造叶子上，这表明这种化合物可能是帮助苍蝇定向到它们寄主栖息地的约会地点的化学线索之一。

Males of tephritid fruit fly species show strong affinity to specific chemicals produced by plants. The oriental fruit fly, Bactrocera dorsalis(and several within its complex species), are strongly attracted to methyl eugenol and some related phenylpropanoids often found as flower fragrances or plant constituents. Males that fed on the attractants selectively converted the compounds into female-attracting pheromone and stored them in the rectal glands. Males scented with the phenylpropanoids were more successful in mating than unscented males, indicating the advantage of acquiring the compound (s) in mating success. Pharmacophagous acquisition of phenylpropanoids by B.dorsalis seems to have evolved within the context of sexual selection, particularly female preference for males "scented" with chemicals derived from plants.On the other hand, alpha-Copaene, a potent attractant for males of Mediterranean fruit fly, Ceratitis capitata, is found as a minor component in the essential oils of various plant species including its major hosts such as orange, guava and mango. Despite such specific attraction, the male flies never feed on the intact compound and hence the biological significance of alpha-copaene remains unknown. In laboratory tests, lek-like behavior of C.capitata was induced artificially using a plastic leaf model treated with(+)-alpha-copaene. It was also found that alpha-copaene affected virgin females provoking 'pseudomale'courtship behavior in the short-range bioassay. Mating occurred exclusively on the artificial leaves treated with alpha-copaene, suggesting the compound serves potentially as one of the chemical cues to facilitate orientation of the flies to the rendezvous site in their host habitat.