Cuticular hydrocarbons in bed bug Cimex lectularius (Heteroptera: Cimicidae) colonies from Argentina?their role in conspecific communication with potential application in pest control

VASSENA, CLAUDIA VIVIANA; CÁCERES, MARIANO; GONZALEZ, PAULA; SANTO ORIHUELA, PABLO LUIS

Manguinhos

Workshop; IV WORKSHOP SUL-AMERICANO DE HETEROPTERA; 2019

Instituto Oswaldo Cruz

During the last 20 years, numerous infestations of Cimex lectularius (L. 1758) have been globally reported. Resistance to insecticides is one of the multiple factors related to sudden bed bug reemergence. Accordingly, we detected a high prevalence of C. lectularius in hotels and dwelling houses in Argentina. Besides, field-collected bed bug colonies exhibited high levels of pyrethroid resistance. In this context, further research efforts should be made to develop new strategies for bed bug control. Using attractants compounds (like pheromones or kairomones) in the ?attract and kill? trapping method could help to monitor infestations. The cuticular hydrocarbons (CHs) comprise a complex mixture of compounds that play functions in desiccation, waterproof and mate recognition in many insect species. Here, we identified the CHs profile in adult bed bugs and analyzed their variation between colonies. Also, we evaluated their role in conspecific communication. Gas chromatography with mass spectrometric detection (GC-MS) was used to obtain CHs profiles from solvent extracts of groups of bed bugs (n=5). The identification was made by comparison with authentic standards retention times, Kovats index, and mass spectra fragmentation. Our results showed that CHs profile includes n-alkanes, mono- and dimethyl-branched, n-alkenes and fatty aldehydes. C29- and C31-alkanes were the most abundant constituents in both sexes, with no significant differences associated with sexual dimorphism. However, the profile of mono- and dimethyl-branched alkanes showed variations between sexes and colonies. Also, we evaluated the role played by CHs of C. lectularius to mediate their aggregation/attractant behavior. Cuticular compounds were obtained by solvent extraction in groups of adults (male or female) and used for the stimuli test in two-choice experimental arena. The activity of insects released in arena was recorded using video-tracking equipment to analyze locomotion variables. Results showed a positive preference by nymphs I towards adults stimuli, and male or females extracts generated attractant behavior in both sexes. The cuticular hydrocarbons in bed bugs could play a major role in protection against desiccation. However, the attractant behavior observed in adults and nymphs could demonstrate their potential role as contact cue in bed bugs.