Abstract
The increase of insecticidal effect by mixture of two organophosphorus insecticides especially of DDVP and other chemicals, was investigated by topical application method using Takatsuki strain of house fly, Musca domestica vicina. The effect of diazinon, malathion and Nankor was fairly improved by mixing with DDVP. The increase of the effect was remarkable in the mixture of Nankor and DDVP. The mixture of ratio of diazinon 2 and DDVP 8, malathion 2 and DDVP 8, and Nankor 5 and DDVP 5 was more effective than the sole DDVP. In all the combinations in the mixture of DDVP and the other chemicals, it seemed that as the content of diazinon, malathion or Nankor decreased the mixtures became more effective. The mixture of diazinon and malathion was more effective than the sole malathion and less than the sole diazinon. Any remarkable increase in the effect was not given by DDVP to Baytex or Dipterex.
