Effect of stereoisomers of the main component of the sex pheromone of Euschistus heros (F.) (Hemiptera: Pentatomidae) in the attractiveness of females

The attractiveness of Euschistus heros (F.) (Hemiptera: Pentatomidae) females to the eight stereoisomers of the methyl 2,6,10-trimethyltridecanoate, major component of the sex pheromone produced by the males of this species, was studied in a double choice olfactometer. Bioassays showed that the (2R, 6R, 10S) stereoisomer was necessary for the attractiveness of females, presenting better results in relation to the others. The stereoisomeric mixture was shown to present significative attractiveness to females, however, when compared to the (2R, 6R, 10S) stereoisomer, it showed lower attractiveness. A atratividade de fêmeas de Euschistus heros (F.) (Hemiptera: Pentatomidae) aos oito estereoisômeros do 2,6,10-trimetiltridecanoato de metila, principal componente do feromônio sexual produzido pelos machos da espécie, foi estudada em olfatômetro de dupla escolha. Os bioensaios demonstraram que o estereoisômero (2R, 6R, 10S) foi necessário para a atratividade das fêmeas até a fonte de odor, destacando-se em relação aos outros. Apesar de exercer atratividade significativa para as fêmeas, a mistura de estereoisômeros quando comparada ao (2R, 6R, 10S) apresentou menor atratividade.