Abstract
A simple, small-bolt method was developed and refi ned for evaluating and screening treatments being considered as prophylactics against bark beetles (Coleoptera: Curculionidae: Scolytinae). Using this method, 4 insecticide products (3 active ingredients) were evaluated against the southern pine beetle, Dendroctonus frontalis Zimmermann, intermittently during a period spanning 1 day to 9 months postapplication. Permethrin (Astro®) showed the best residual effectiveness as determined by the small-bolt assay, followed by bifenthrin (Onyx®) and carbaryl (Ferti-Lome® and Sevin XLR Plus®). Bifenthrin has been reported as effective in fi eld tests with D. frontalis and carbaryl as ineffective, lending credence to the small-bolt method. Results with permethrin suggest that a more extensive evaluation may be warranted for this active ingredient. The method as developed provides a useful and effi cient tool for identifying preventive treatments that are unlikely to be effective against D. frontalis. Its use for screening ineffective products would limit expensive and time-consuming fi eld evaluations to treatments that show signifi cant promise. With additional refi nement, the small-bolt assay may provide most of the benefi ts of more costly testing methods while offering suffi cient fl exibility for comparing prophylactic treatments that rely on different modes of action.
Keywords
pesticide evaluation,
bioassay,
prophylactic pesticides,
pyrethroids,
residual efficacy,
dendroctonus
Citation
Strom, B.L.; Roton, L.M. 2010. A small-bolt method for screening tree protectants against bark beetles (coleoptera: curculionidae). J. Entomol. Sci. 44(4): 1-12
