Development of a new formulation using fenitrothion MC, "K5-123", as a cockroach bait : I. The insecticidal activity on laboratory evaluation

Abstract

We prepared a candidate bait formulation, K5-123, containing microencapsulated fenitrothion, already registered in Japan, as an active ingredient. And we evaluated the insecticidal activity for German and smokey brown cockroaches in comparison with those of some cockroach bait products using various kinds of laboratory test method. In small container (W20cm×L35cm) test, K5-123 got to 100% mortality at one day for German cockroaches and at 5 days for Smokey brown cockroaches after treatment, but a boric acid product got to 100% mortality at 8 days and at 12 days respectively. And in large container (1m²) test for German cockroaches, K5-123 also got to 100% mortality at 2 days after 5g treatment. Transferring killing effect of K5-123 for German cockroaches was tried to evaluate by giving the dead bodies or the feces of the cockroaches after treatment with bait to untreated colony in comparison with those of a hydramethylnon (gel) product. The results showed K5-123 was superior to a hydramethylnon on transferring effect. From these results described above, it can be said this formulation is expected to be used in practice.