Activity of the German Cockroach, Blattella germanica (L.) (Orthoptera: Blattellidae), at Different Microhabitats in Semi-natural Conditions when Treated with Sublethal Doses of Chlorpyrifos and Permethrin^*

Male adults of a mutant, or (orange body), and KNIH (Korea National Institute of Health) strains of the German cockroach, Blattella germanica (L.), were individually treated with chlorpyrifos and permethrin in sublethal doses. Local activity at different microhabitats for harborage, food, water, and other neighbor cockroaches was measured by observing visiting frequency for 4∼5 days continuously after the chemical treatment. Also long-range activity was observed by counting the number of crossing imaginary center-lines within the observation cage during the observation period. The local activity was generally decreased after the treatment of chemicals at most microhabitats. Trends of the activity observed in the control also appeared in response to the chemical treatments; local activity was the highest at harborage, and was low at the other microhabitats. The diel difference observed in the local activity, however, disappeared in the or strain by the treatment of both insecticides. Especially high values in local and long-range activity at scotophase were decreased greatly. In the KNIH strain, the local activity was less affected with chlorpyrifos. Diel difference persisted in the chlorpyrifos treatment, but disappeared in the permethrin treatment. The long-range activity was increased in the chlorpyrifos treatment in the KNIH strain.