Responses of Susceptible and Cyfluthrin-Resistant Broiler House Populations of Lesser Mealworm (Coleoptera: Tenebrionidae) to γ-Cyhalothrin

Abstract

Gamma-Cyhalothrin was proposed as an agent for management of lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae), in Australian broiler houses. From 2007 to 2009, baseline susceptibility of 20 Australian broiler farm beetle populations plus an insecticide-susceptible laboratory population was determined for gamma-cyhalothrin by using topical application. In addition, repeat testing and regression analyses of specific beetle populations to gamma-cyhalothrin showed that topical application was a very reliable and repeatable testing method. The 21 populations were tested with a cyfluthrin discriminating concentration (based on LC(99.9), 0.0007% [AI]) to identify possible cross-resistance. Across all populations, there was a significant linear relationship between the gamma-cyhalothrin LC50 value and mortality induced by the cyfluthrin LC(99.9). Full cyfluthrin baseline studies of seven populations indicated that gamma-cyhalothrin was twice as toxic as cyfluthrin, even against susceptible beetles and resistance ratios at the cyfluthrin LC50 and LC(99.9), varied considerably, with maxima of 56.6 and 83.6 respectively. Corresponding ratios for gamma-cyhalothrin for the same populations were 8.6 (LC50) and 7.9 (LC(99.9)). There were no significant correlations between beetle weights and gamma-cyhalothrin LC50 or LC(99.9), values. A discriminating concentration of 0.005% (AI) gamma-cyhalothrin was chosen to detect any future changes in susceptibility. Results of this study suggest that cyfluthrin can confer cross-resistance to gamma-cyhalothrin in A. diaperinus, but the magnitude of this resistance is unpredictable. Thus, widespread and frequent cyfluthrin use in broiler houses in eastern Australia, which has selected for cyfluthrin resistance, also has resulted in reduced susceptibility to gamma-cyhalothrin. Due to its higher relative toxicity, gamma-cyhalothrin is still potentially useful for management of lesser mealworm, but due to cross-resistance issues, adoption of gamma-cyhalothrin for broiler house use will require a cautious and judicious approach.

Metabolic Mechanisms Only Partially Explain Resistance to Pyrethroids in Australian Broiler House Populations of Lesser Mealworm (Coleoptera: Tenebrionidae)

“…In the United States, insecticides currently registered for application in poultry facilities include the pyrethroids cyßuthrin, ␤-cyßuthrin, -cyhalothrin, ␥-cyhalothrin, permethrin, esfenvalerate, and bifenthrin; the organophosphates tetrachlorvinphos, dichlorvos and chlopyrifos; and carbaryl spinosad, pyriproxyfen, and imidacloprid (Stringham and Watson 2008, Tomberlin et al 2008, Hinkle 2010. Far fewer insecticides are available for broiler house application in Australia and of these insecticides, cyßuthrin is used most frequently, followed by fenitrothion and spinosad; ␥-cyhalothrin is currently being considered for registration (Lambkin and Rice 2010).…”

Application of Spinosad Increases the Susceptibility of Insecticide-Resistant <I>Alphitobius diaperinus</I> (Coleoptera: Tenebrionidae) to Pyrethroids

“…Control beetles were supplied with kibbled wheat in a glass jar in the same manner. Beetles were incubated at 25ЊC and 55% RH and then mortality was assessed August 2014 LAMBKIN AND FURLONG: MITIGATION OF PYRETHROID RESISTANCE BY SPINOSAD by pouring beetles onto a large Þlter paper (125 mm in diameter), and their ability to walk relative to the control beetles was assessed (Lambkin 2005, Lambkin and Rice 2006, Lambkin et al 2010. Mortality assessments were made after 24 h for cyßuthrin-, ␥-cyhalothrin-, and spinosad-treated beetles and after 48 h for fenitrothion-treated beetles.…”

“…For these regressions, complementary logÐlog link with a log transform of the dose was used for ␥-cyhalothrin, and probit was used for cyßuthrin and spinosad. The complimentary logÐlog link analysis was chosen for ␥-cyhalothrin, as it provided a better Þt to these data (Lambkin et al 2010). Interaction Field Study on 11 Queensland Broiler Farms.…”

“…In Australia, four insecticides, fenitrothion, cyßuthrin, ␤-cyßuthrin, and spinosad, are currently registered for use against the pest in broiler houses, and another compound, ␥-cyhalothrin, has been laboratory tested (Lambkin et al 2010). Many broiler house beetle populations in eastern Australia are highly resistant to fenitrothion (Lambkin 2005) and cyßuthrin (Lambkin andRice 2006, Lambkin andFurlong 2011).…”

Development of pull and push–pull systems for management of lesser mealworm, Alphitobius diaperinus, in poultry houses using alarm and aggregation pheromones

“…Control of A. diaperinus in poultry houses is currently undertaken using intensive insecticide application, causing potential contamination of poultry and aviaries, and threatening the delivery of safe food . Additionally, due to the cryptic behaviour of this pest, insecticide control is usually not effective . In recent years, several alternative methods for lesser mealworm control have been proposed, with the aim of minimizing the use of insecticides and enhancing the quality of the food that is being produced .…”