ALPHACYPERMETHRINIFLUFENOXURON - A NEW HIGH PERFORMANCE RESIDUAL INSECTICIDE COMBINATION FOR COCKROACH CONTROL

Abstract:
A formulation consisting of the pyrethroid insecticide alphacypermethrin and flufenoxuron, an acylurea insect growth regulator, has been shown to give effective and persistent control of cockroach infestations after a single treatment. Flufenoxuron is a new high performance residual insecticide for public hygiene pest control which kills insects by interference with chitin formation. Failure of the chitin to develop properly results in the death of arthropods during ecdysis. Although not an adulticide, a high proportion of eggs laid by an adult after exposure to flufenoxuron are non-viable. Combining alphacypermethrin and flufenoxuron ensures both persistence and effective insecticidal activity at all stages of the pest life-cycle. A one-pack mixture formulated as a suspension concentrate containing 60/30 g/L of alphacypermethrin / flufenoxuron was applied to give a deposit of 15.0 / 7.5 mg ai/m2 in apartments infested with Blattella germanica and Blatta orientalis. The treatment gave rapid and extended control of both species (eradication by 1 month, maintained until the end of the trial at 13 months). The level of alphacypermethrin was reduced to 30 g/L to give a 30 / 30 g/L SC alphacypermethrin / flufenoxuron mixture. This formulation was applied to give a deposit of 7.517.5 mg ailm2 in two further trials to apartments infested with B. orientalis. In the first trial, eradication was achieved in most apartments by 2 months post-treatment and throughout the trial site by 9 months post-treatment. This was maintained until the trial was terminated at 12 months. In the second of these trials, eradication was achieved by 9 months post-treatment in five of the six apartments treated, and was maintained until the end of the trial at 12 months. In the remaining apartment, 96.5% and 99.0% control was achieved by 9 and 12 months, respectively. A further trial was carried out at a pig farm with a high B. orientalis infestation using the 30 / 30 g/L SC mixture applied to give a deposit of 7.5 / 7.5 mg ai / m2. An infestation at the farmhouse was reduced by 81% and 95% after 17 and 42 days post-treatment, respectively. Two re-infestations of the farmhouse were successfully controlled, the first by treatment of the pig unit nearest the house and the second, 409 days after the initial treatment of the farmhouse, by a second application which resulted in 98% control and eradication by 17 and 171 days post-treatment, respectively. Using such a combination of insecticides with different modes of action should prove to be an effective management strategy to follow for professional cockroach control, particularly in situations where resistance is suspected.