BEHAVIORAL RESISTANCE OF FIELD-COLLECTED GERMAN COCKROACHES (BLATTODEA, BLATTELLIDAE) TO BAITS CONTAINING GLUCOSE

German cockroaches, Blattella germanica (L.), collected from an number of field locations, ranging from Florida to South Korea, displayed an avoidance behavior to a bait formulation. Cockroaches collected from locations that had a history of treatment with this formulation demons trated bait avoidance, whereas laboratory and field strains with no pr ior exposure ingested and were susceptible to the toxic bait. Thus, be havioral resistance had evolved in these insects. Selection experiment s showed that several susceptible strains were potentially capable of developing behavioral resistance. Strains that avoided ingesting bait also displayed an aversion to glucose, which is a component of the bai t that is typically phagostimulatory. Substitution of fructose for glu cose in toxic baits significantly improved bait efficacy.