Confirmation of insecticide resistance in Cimex lectulariusLinnaeus (Hemiptera: Cimicidae) in Australia

Abstract

Insecticide resistance in the common bed bug, Cimex lectulariusLinnaeus has been suspected in Australia with anecdotal reports of poor product performance. To investigate this possibility, LD50 values were determined via topical application of technical grade permethrin, deltamethrin, bendiocarb, pirimiphos-methyl and imidacloprid serially diluted in acetone to a suspected resistant field-collected strain and a susceptible laboratory strain. All compounds tested against the susceptible strain were efficacious. However, for the field strain, only pirimiphos-methyl and imidacloprid showed high levels of activity. Resistance was confirmed in the field-collected strain to the pyrethroids and bendiocarb, but not to pirimiphos-methyl or imidacloprid. Resistance factors ('resistant' LD50/susceptible LD50) for each compound were: permethrin≈1.235 million, deltamethrin≈370000, bendiocarb≈250, pirimiphos-methyl=2.6, imidacloprid=2.6. Bendiocarb, permethrin and deltamethrin all failed to return greater than 60% mortality at the maximum dose of 100μg/μL. This research has significant operational implications for bed bug control and the registration process of new products in Australia.