Muller_1983_Angew.Parasitol_24_156

UTH WP 50-7 (active agent: trichlophenidine) proved to be very effective against the housefly Musca domestica and shows favourable toxicological features. However, in several cases the repeated and exclusive usage of this insecticide caused a quick development to highly resistant populations. The resistance applies to DDT but not to pyrethrum + piperonylbutoxid. Our results were compared with those from Denmark and discussed with regard to the mechanisms of DDT-resistance in Musca domestica. Selection with trichlophenidine did not increase resistance to dimethoate and vice versa. The frequent application of aerosols with pyrethrum + piperonylbutoxid had no influence on the degree of resistance against trichlophenidine. According to the hitherto existing results it seems feasible and recommendable to use the insecticides UTH WP 50-7, Bi 58 (a.i.: dimethoate) and Py ULV 10/78 alternately in case the combination of chemical and non-chemical measures, which should be given preference, is impossible.