Baseline responses of Alphitobius diaperinus (Coleoptera: Tenebrionidae) to spinosad, and susceptibility of broiler populations in Eastern and Southern Australia.
Spinosad was proposed as a potential chemical for control of lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae), in Australian broiler houses after the detection of strong cyfluthrin resistance in many beetle populations. In 2004-2006, spinosad susceptibility of 13 beetle populations from eastern and southern Australian broiler houses and a cyfluthrin/fenitrothion-resistant reference population was determined using topical application, and was compared with the susceptibility of an insecticide-susceptible reference population. Comparisons of dose-response curves and baseline data showed that all populations, including the insecticide-susceptible population, were roughly equivalent in their response to spinosad, indicating no preexisting spinosad resistance. Two field populations, including the resistant reference population, which had confirmed cyfluthrin/fenitrothion-resistance, showed no cross-resistance to spinosad. There was no significant correlation between beetle weight and LC9.9. A discriminating concentration of 3% spinosad was set to separate resistant and susceptible individuals. Considering the levels of spinosad resistance that have been recorded in other insect pests, the sustained future usefulness of spinosad as a broiler house treatment will rely on effective integrated beetle management programs combined with carefully planned chemical use strategies.
Lambkin
Trevor A
TA
Queensland Department of Primary Industries and Fisheries, Animal Science, 665 Fairfield Road, Yeerongpilly, Qld 4105, Australia. trevor.lambkin@dpi.qld.gov.au
Rice
Steven J
SJ
D000818:Animals; D001315:Australia; D001835:Body Weight; D002645:Chickens; D001517:Coleoptera / Q000033:anatomy & histology; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D006799:Housing, Animal; D007305:Insecticide Resistance; D007306:Insecticides; D018942:Macrolides / Q000008:administration & dosage; D013021:South Australia; D018675:Toxicity Tests
D004338:Drug Combinations; D007306:Insecticides; D018942:Macrolides; C415329:spinosad