Submitted to: Ecological Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/9/2000
Publication Date: 4/20/2001
Citation: Rojas, M.G., Morales Ramos, J.A. 2001. A bait matrix for delivery of chitin synthesis inhibitors to the formosan subterranean termite, coptotermes formosanus (isoptera: rhinotermitidae). Ecological Entomology. Interpretive Summary: The Formosan subterranean termite (FST) (Coptotermes formosanus) is an imported pest in the U.S.A. This insect is causing extensive damage to houses and trees in the Greater New Orleans area and 14 other U.S. states with annual losses in the millions of dollars. Thanks to this research work we were able to increase preference of the bait matrix by the inclusion of key supplements involved in termite nutrition. This made the matrix nine times more preferred by these termites when compared to wood or other cellulose-based products. This preference makes it ideal for use as a toxin-carrier. Because termites consume large amounts of it more rapidly than other matrices, lower concentrations of chemicals can be used to kill colonies in a shorter period of time. The matrix is being patented and co-exclusive licenses have been negotiated with three companies for its use in commercial termite control products. The improvement of baiting systems is important because it gives us the tools requried to increase control and reduce the amount of toxins incorporated into the soil.
Technical Abstract: The efficacy of three chitin synthesis inhibitors (CSI), diflubenzuron, hexaflumoron, and chlorfluazuron, incorporated into a new bait matrix to kill the Formosan subterranean termite, Coptotermes formosanus Shiraki, was evaluated in the laboratory. Bait formulations containing 250 ppm of the three CSIs were presented to termite nests with 2,500 individuals (80% workers and 20% soldiers) in the presence of alternative food sources consisting of cardboard and Southern yellow pine wood. None of the bait formulations were a significant repellent or feeding deterrent to the termite workers as evidenced by the lack of consumption on the alternative food sources. All nests presented with the bait formulations died within 8 wk, while the control nests (bait with no CSI) remained alive 6 months after the end of the study. No significant differences in consumption were observed among the CSI treatments, but consumption was significantly higher in the control group. Significance of this study for the improvement of current bait technology is discussed.