New Analogs of Sex Pheromones of American Cockroach (periplaneta Americana L.): Behavioral and Electroantennographic Study

New chemical analogs as well as 2 main components, PA and PB, of the sex pheromone of Periplaneta americana L. have been studied by our original behavioral technique and electroantennogram recording. Behavioral assays included measurements of dose–response relationship and testing the effect of the analogs on peri-planones perception. Among 9 analogs, 7 elicited typical sex behavior of males. According to the shape of behavioral dose–response curves, three analogs can be separated as PA-like and two as PB-like. The facilitating effect of PA and the adapting effect of PB were shown towards both main components of the pheromone. Three analogs can modify the sexual behavior of males in response to PA or PB. The electrophysiological study consisted of the analysis of six kinetics parameters of the electroantennogram. Dose–response relationships for these parameters were measured for each substance. When we compared doses of the substances that elicited the same amplitudes of the electroantennogram, activities of the analogs appeared to be from 10 to 300 000 times less than those of PB. The corresponding dose–response curves of the same electroantennogram parameters were found to have different slopes to the dose axis for different substances, therefore linear parts of all those curves were approximated by linear regression. Each substance had a distinct set of “X-coefficients” of regression for a set of the parameters of electroantennogram kinetics. Among the analogs, the substance M5 is of greatest interest because of its high behavioral and electroantennographic activity, very low value of the plateau of the electroantennogram as well as the additional peak on the rising phase of the electroantennogram. Nauji amerikinio tarakono (Periplaneta americana L.) lytinio feromono analogai: elgesio ir elektrofiziologiniai tyrimai