Submitted to: Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/15/2009
Publication Date: 5/1/2009
Citation: Arthur, F.H. 2009. Efficacy of Chlorfenapyr Against Adult Tribolium castaneum Exposed on Concrete: Effects of Exposure Interval, Concentration, and the Presence of a Food Source After Exposure. Insect Science. 16: 157-163.
Interpretive Summary: Phantom® is a new insecticide that was labeled in 2007 to control stored-product insects inside mills, warehouses, and processing plants, but there is no information concerning the effects of presence of food on survival after insects are exposed on a surface treated with Phantom®. We exposed adult red flour beetles, a major pest of flour mills, for different times on concrete treated with a range of concentrations of Phantom®, removed the beetles from the treated surface, and held them for 7 days either with or without whole-wheat flour. In the absence of flour, beetle survival steadily decreased during the 7-day holding period, at all time periods for which they were exposed on all concentrations of Phantom®. When beetles were given flour, they were able to survive exposure to the insecticide, regardless of concentration and exposure period, and this level of survival was generally much greater compared to beetles that were not given flour after exposure. Results show that Phantom® can be used to control the red flour beetle inside flour mills, but sanitation and cleaning to remove available flour food sources should be done as well to ensure that the insecticide application will be effective.
Technical Abstract: Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1.1, 0.825, 0.55, and 0.275 g of active ingredient m2. Adult Tribolium castaneum (Herbst), the red flour beetle were exposed for 2, 4, or 8 hours at each concentration, then removed and held either with or without food (wheat flour) for 7 days. Survival was assessed when the beetles were removed from the exposure arenas and daily during the post-exposure period. In the presence of food, survival was high regardless of concentration and the day post-treatment on which survival was assessed, but survival did decrease as the exposure period increased from 4 to 8 hours. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post exposure assessments. This pattern of decrease could be described by linear and non-linear equations. Results show the presence of food material greatly compromised effectiveness of the insecticide, and emphasize the importance of cleaning and sanitation in conjunction with insecticide treatments.