Biological activity of chemicals identified from extracts and volatiles of maleRhagoletis cerasi.

Fractions obtained by chromatographic separation of extracts and volatiles from maleRhagoletis cerasi flies were tested for biological activity on females under laboratory conditions. During the bioassays, the number of incoming flies as well as the time spent by individual flies on the area of stimulus were taken under consideration. Two distinct types of female behavior were observed, i.e., attraction and arrestant behavior. GC-MS analysis of biologically active fractions resulted in tentative identification of 75 compounds. EAG screening for 27 of these compounds was performed, and subsequent laboratory bioassays resulted in the confirmation of arrestant activity for various mixtures of eight fatty acids (octadecanoic, nonadecanoic, eicosatetraenoic, eicosapenaenoic, eicosaenoic, heneicosanoic, docosahexenoic, and docosanoic). Following EAG tests and laboratory bioassays, a possible mode of chemical communication of this species with sex pheromones is proposed.