Activacion and orientacion of Rhodnius prolixus males in response to odors emitted by females

GINA B. PONTES; CLAUDIA A. ZACHARIAS; GABRIEL MANRIQUE; MARCELO G LORENZO

Congreso; II ALAEQ; 2012

The existence of a pheromone emitted during copulation was reported for Rhodnius prolixus bugs. Adults possess one pair of metasternal glands that emit volatile products identified and reported to be released mainly at night. We investigated here if these volatile signals emitted by adult R. prolixus can modulate sexual-related behaviours of opposite and/or same gender individuals. We first used a shelter bioassay to characterize if activity patterns of males or females are affected by chemical signals emitted by opposite gender conspecifics. We found that males left their shelter more frequently in the presence of females showing higher activity and an increased number of copulation attempts. Females showed no shelter-related activation in presence of male odors. Secondly, we used a dual-choice walking compensator device to investigate whether females or males show oriented responses to odors from adults. We showed that males oriented towards air currents carrying female odors but females did not orient towards odors emitted by adults. Finally, we tested if female metasternal glands compounds modulate male orientation responses and verified that males did not orient in the absence of female metasternal glands compounds. Thus, a volatile chemical signal emitted by females promoted the activation of sheltered males and their orientation when these volatiles were carried by air currents.