Chemical analyses, using Solid Phase Microextraction and GC-EAD, of head space volatiles from hawthorn and flowering dogwood fruit have resulted in the identification of unique mixtures that show high levels of behavioral activity. Flight tunnel studies showed that flies reared from each fruit type can discriminate between the different volatile blends, and also between their own host fruit and previously identified volatiles from domestic apple. Individual flies display odor-modulated anemotaxis over a 1 m distance to colored spheres releasing different fruit odor mixtures or single compounds. Tests also show that chemicals within two of the volatile mixtures can act as behavioral antagonists, causing arrestment of upwind flight when presented in another species volatile mix. The results are discussed in relation to the potential role of host fruit odors in sympatric speciation within the Rhagoletis species complex.
Species 1: Diptera Tephritidae Rhagoletis pomonella
Keywords: flight tunnel, odor discrimination
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA