Areawide field study on effect of three chitin synthesis inhibitor baits on populations of Coptotermes formosanus and Reticulitermes flavipes (Isoptera: Rhinotermitidae)

Abstract

Periodic sampling of 43 independent monitors, initially active with Formosan subterranean termite, Coptotermes formosanus Shiraki, or the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae), was conducted to evaluate the effects of cellulose baits containing one of three chitin synthesis inhibitors (CSIs) - diflubenzuron, hexaflumuron, or chlorfluazuron - on termite populations. Diflubenzuron at 0.1% active ingredient (AI, wt:wt) had no noticeable effect on termite populations. Chlorfluazuron (0.25% [AI]) significantly reduced termite populations in ≈3 yr. Chlorfluazuron used after >2-yr diflubenzuron treatment significantly reduced termite populations within months. This suggests diflubenzuron exposure increased the termite's sensitivity to chlorfluazuron accelerating population collapse. Hexaflumuron (0.5% [AI] ) also reduced termite populations in ≈2 yr. The process of removing most detectable termite populations from the ≈460,000-m 2 campus of the Southern Regional Research Center, New Orleans, LA, with CSIs baits required ≈3 yr. Adjustments in the specific bait formulations and application procedures might reduce time to suppression. Establishment of new independent termite populations provides a mechanism to minimize the effects of baits. Remedial control measures around and under structures should be considered when implementing an area wide management strategy. © 2011 Entomological Society of America.