Chemical symphony: Unraveling triatomine aggregation and attraction patterns for innovative pest control solutions

Aggregation is a spatial distribution pattern where individuals can be grouped through interaction with particular signals or cues [e.g., chemical substances]. Numerous triatomine species exhibit attraction and aggregation around both conspecific and heterospecific feces. It remains unclear whether compounds released by feces function as signals (pheromones or synomones) or cues. Employing a bioassay that mimics field conditions, we investigated the response of Triatoma pallidipennis bugs to volatiles present in its feces and blends of these compounds. Our findings indicate that short-chain aldehydes, namely nonanal, octanal, heptanal, and hexanal, attract fifth-instar nymphs. Furthermore, insects responded to individual compounds as well as secondary, ternary, and quaternary blends. The most attractive blend consisted of all four aldehydes. Additionally, quaternary blends at various compound ratios attracted fifth-instar nymphs of T. phyllosoma and T. longipennis. We discuss the potential roles of these compounds as signals or cues and explore their application as bait in control programs.