Repelência de secreções das glândulas pigidiais do besouro rolador Canthon smaragdulus (Scarabaeidae: Scarabeinae) sobre a formiga Tapinoma melanocephalum (Formicidae: Dolichoderinae)

Abstract

Chemical repellents of insects play an important role in pest control. These products are of high interest because unlike insecticides they generally exhibit low toxicity for the environment or humans. In recent years the number of research to develop chemical repellents has therefore increased. Validating meaningful tests to understand how chemical repellents change the behavior of target insects is of paramount importance. The ant Tapinoma melanocephalum is considered a significant urban pest that causes many economic losses, in addition to transmitting disease. The dung roller beetles C. smaragdulus makes resources balls, and the impregnate with pygidial gland secretions, that exhibit defensive functions against predador ants. In this context, we investigated the possible repellency of pygidium secretions of males and females of the dung beetle C. smaragdulus (Coleoptera: Scarabaeinae) on T. melanocephalum, and if a larger amount of pygidial secretions of the male beetles present a larger effect on ant behavior. To explore behavioral modifications associated with the secretions, we collected pygidial secretions of dung beetles and conducted repellency tests in an arena. T. melanocephalum workers were placed in the center of the arena and their behavior were analyzed blindly with Ethovision 7.0 (Noldus). Our results thus suggest that dung beetle pygidial secretions presents a potential repellency to the ants and that female secretions of C. smaragdulus may have a higher repellency effect on the ants and how much the amount of male pygidial secretions of C. smaragdulus more behavior of the pest ant was change. Dung beetles have developed pygidial secretions with some biological potential against the species that can use the same resources. It would be interesting to conduct more experiments to assess the effect of pygidial secretions on recruitment ant T. melanocephalum at the collective level.