OPTIMIZATION OF A CO2-FREE SYNTHETIC HOST ODOR LURE TO TRAP TRIATOMINES

GUIDOBALDI F; BRATOVICH C; GARCIA MAILEN; GUERENSTEIN PG

Natal

Congreso; VIII Encontro Brasileiro de Ecologia Química; 2013

Vector control is the most effective method to prevent Chagas disease. A lured trap device is a sustainable and an environmentally-friendly tool for vector monitoring and control. Using electrophysiological recordings from antenna sensilla (e.g., J Exp Biol 204:585, 2001) and behavioral tests (e.g., Chem Senses 29:833, 2004) a number of host odors that are detected by triatomines were identified. All triatomine-detected host odors are also detected by mosquitoes (Olfact in Vector-Host Interact, Chap. 14). Thus, we tested a CO2-free synthetic host-odor lure for mosquitoes (Sweetscent®; consisting on ammonia, L(+)-lactic acid and hexanoic acid) and found it significantly attractive for triatomines. Using a dual-choice olfactometer in which attracted bugs get trapped, we now aim at optimizing the performance of a CO2-free synthetic host odor blend to attract the bugs. We tested different blends consisting on ammonium hydroxide, L(+)-lactic acid and pentanoic acid varying the total mass of compounds and their proportions. Each odor was loaded onto an individual filter paper strip and the three strips were placed in the test arm of the olfactometer. The negative-control arm contained filter paper strips with the solvent (water) only. In negative-control experiments both arms consisted in control arms. The percentage of total capture (%TC) was defined as the total number of insects in the arms (test + control) over the total of insects tested. Insects were assayed individually and experiments lasted a single night. Thus, we compared the odor-induced %TCs with those of the basal %TCs obtained in the negative-control experiments. Two of the synthetic blends tested evoked significant %TC (Blend 4: 28.1 %, G-test, P