Fumio Harada

Insecticide Susceptibility Tests and Indoor Control Tests by DDVP Strips against Several Confectionery Pests

In order to know the effects of eight insecticides, susceptibility tests were carried out by the topical application method on the several important confectionery pests such as cigarette beetles (Lasioderma serricorne), Indian meal mothes (Plodia interpunctella), sawtoothed grain beetles (Oryzaephilus surinamensis), rice weevils (Sitophilus zeamais) and Adzuki bean weevils (Callosobruchus chinensis).The results showed that comparing with the common house mosquito (Culex pipiens pallens), the house fly (Musca domestica vicina) and the German cockroach (Blattella germanica), these insects had high tolerance levels, but they were susceptible to pyrethorins and sumithion (fenitrothion) than other insecticides tested. According to the KT50 values, relatives, toxicities of the insecticides were as follows; pyrethorins>sumithion>malathion> lindane>alethrin>DDT>DDVP for the cigarette beetle and pyrethrins>DDVP>sumithion=phtalthrin>lindane>malathion for the Indian meal moth, respectivity.Effectiveness of DDVP strips upon the saw-toothed grain beetle, the cigarette beetle, the yellow mealworm (Tenebrio molitor), the Adzuki bean weevil and the Indian meal moth were tested with a box (0.5m3) in which the insects were exposed by the strips. From the test results, susceptibilities assessed by the KT50 values as follows; common house mosquito house fly>Indian meal moth>saw-toothed grain beetle>German cockroach>American cockroach>yellow mealworm>cigarette beetle. It is clear from the data presented that the DDVP strips can be used in practice under limited conditions for the control of these insects.