Abstract
Field trials of K5-123 for cockroach control were conducted twice at a restaurant in Osaka Prefecture, 1995-1996.
Nineteen sticky traps were set all over the restaurant (around 33m2) and population density of cockroaches was caliculated by ordinary procedure.
Initial density of the population in the place was more than 36 (individuals/sticky trap/day) and the cockroach species was German cockroach only.
First trial was made by using only K5-123 which was treated at 5.5g/m2 like line and spot to near by their habitat as possible and to the corner area of the floor, furnitures, sinks, refrigerators and etc. Population density declined to below almost 5 after 14 days and gradually decreased down to 2 after 1 month. And then, it was going to recover after 77 days.
Second trial was conducted by using both K5-123 and fenitrothion 20% MC formulation as residual spray soon after the first trial. K5-123 was newly treated in the same way as the first trial treatment after the residue of K5-123 were removed. And 50 folds water dilution of fenitrothion 20% MC was sprayed to corners of the floor and up to 1.5m height of wall surface of the cooking room at the rate of 50ml/m2. The density was decreased up to 0.2 after 1 month and kept such the low level for more than 9 months.
From these results, K5-123 is convinced to be useful inpractice for cockroach control. However, it was suggested there are some limits in single bait treatment for cockroach control, because the control area like a restaurant is of heavy complex structures and with abandant foods which are cockroach's favorite. And it was of great interest that when bait accompanied with residual spray was treated, its effect was much greater than those of single bait treatment.
