TEMPERATURE EFFECT ON THE INSECTICIDAL ACTIVITY OF PYRETHROIDS ON TRIATOMA-INFESTANS

1. The toxic effect of deltamethrin, asymmethrin, alphamethrin, cyperm ethrin and cypermethrin High cis in nymphs III of Triatoma infestans w as lower at 28 than 16-degrees-C. 2. Prostration in treated nymphs III occurred more rapidly at 28 than 16-degrees-C. 3. Symptoms of poisoni ng rapidly disappeared when nymphs III intoxicated were moved from 16 to 28-degrees-C. 4. Nymphs III exposed to low doses of pyrethroids at 28-degrees-C, which did not show symptoms of poisoning, were rapidly a ffected when they were moved to 16-degrees-C.