The Bait Preference of American Cockroach (Periplaneta americana): Field and Laboratory Strains

Background: American cockroaches (Periplaneta americana) need to be controlled because of their ability to cause ill-health effects to humans. Toxic gel baits are one effective control method for cockroach control. P. americana are thought to prefer toxic baits over other food sources and may skew our understanding of bait preference in natural strains. Therefore, this study aimed to understand the bait preference of P. americana field (naturalised Semarang) and laboratory (reared) strains. Methods: Fifteen adults P. americana were tested in a Bioassay experiment using a four-choice olfactometer. After being starved for 24 hours, the cockroaches were given two insecticides and two natural foods: Maxforce® (Hydramethylnon 2%), Optigard® (Emamectin Benzoate 0.1%), cooked rice and banana (Musa textilis) for 120 minutes. The number of visits frequency by cockroaches to each bait was counted and analysed using one-way Analysis of Variance. Results: The study found that there was no significant bait preference in either field strains or laboratory strains (P > 0.05) of P. americana, although field strains tended to visit natural foods more often, and laboratory strains visited insecticide baits more frequently. Conclusion: This study suggests P. americana field and laboratory strains are not fully attracted to the gel baits when other foods are available around their harbourage. Therefore, the recommendation is to minimize the availability of other food sources when applying gel baits around the cockroach harbourage. Further research is required.