Yee Wee L, Goughnour Robert B, Feder Jeffrey L, Linn Charles E, Cha Dong H
USDA-ARS, Yakima Agricultural Research Laboratory, Wapato, WA 98951.
Washington State University, Vancouver, Research and Extension Unit, Vancouver, WA 98665.
Environ Entomol. 2017 Dec 8;46(6):1351-1358. doi: 10.1093/ee/nvx130.
Rhagoletis zephyria Snow and Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) are morphologically similar flies that attack white-colored snowberry fruit (Symphoricarpos spp.) and yellow/red or dark-colored apple/hawthorn fruit (Malus/Crataegus spp.), respectively. The two flies are caught together on traps in R. pomonella surveys in the western United States, increasing labor needed to process catches. Comparing responses of the two species with different traps could help identify best practices for reducing R. zephyria captures in these surveys and could contribute to understanding population divergence in Rhagoletis flies. In Washington State, United States, we found that R. zephyria responded most to yellow rectangles and more to white than red spheres (RSs) baited with ammonium carbonate (AC), whereas R. pomonella responded most to RSs with AC. Yellow plastic rectangles with AC were more effective in capturing R. zephyria than cardboard rectangles, as has been found for R. pomonella. R. zephyria did not respond to apple fruit volatiles associated with RSs that were attractive to R. pomonella. In contrast, R. zephyria responded more to yellow rectangles with snowberry than apple volatiles. Both species responded to AC. Our results suggest that RSs are better than yellow rectangles for surveying R. pomonella when snowberries are abundant. However, if discrimination from R. zephyria is paramount, RSs with apple volatiles should be used. Differences in the species' responses to traps appear related to odor/color cues of the flies' host fruit, while commonalties appear related to visual/olfactory stimuli associated with protein feeding, for which AC is a general attractant.
雪氏悬果蝇（Rhagoletis zephyria Snow）和苹果实蝇（Rhagoletis pomonella (Walsh)）（双翅目：实蝇科）是形态相似的果蝇，分别侵害白色的雪果（毛核木属植物）和黄色/红色或深色的苹果/山楂果实（苹果属/山楂属植物）。在美国西部进行的苹果实蝇调查中，这两种果蝇会一起被诱捕器捕获，增加了处理捕获物所需的工作量。比较这两个物种对不同诱捕器的反应，有助于确定在这些调查中减少雪氏悬果蝇捕获量的最佳方法，并有助于理解悬果蝇种群的分化情况。在美国华盛顿州，我们发现雪氏悬果蝇对黄色矩形诱捕器反应最为强烈，对用碳酸铵（AC）诱饵的白色诱捕器的反应比对红色球体诱捕器（RSs）的反应更强，而苹果实蝇对用AC诱饵的RSs反应最为强烈。正如对苹果实蝇的研究结果所示，带有AC的黄色塑料矩形诱捕器在捕获雪氏悬果蝇方面比纸板矩形诱捕器更有效。雪氏悬果蝇对与吸引苹果实蝇的RSs相关的苹果果实挥发物没有反应。相反，雪氏悬果蝇对带有雪果挥发物而非苹果挥发物的黄色矩形诱捕器反应更强。两种果蝇都对AC有反应。我们的结果表明，当雪果丰富时，RSs在调查苹果实蝇方面比黄色矩形诱捕器更好。然而，如果区分雪氏悬果蝇至关重要，则应使用带有苹果挥发物的RSs。这两个物种对诱捕器反应的差异似乎与果蝇寄主果实的气味/颜色线索有关，而共同点似乎与与蛋白质摄食相关的视觉/嗅觉刺激有关，AC是一种通用引诱剂。
