Some Organic Acids Acting as Stimulants of Recruitment and Feeding for the Formosan Subterranean Termite (Isoptera: Rhinotermitidae)

Authors: Morales Ramos, Juan; Rojas, Maria - Guadalupe

Submitted to: Sociobiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2009
Publication Date: 10/1/2009
Citation: Morales Ramos, J.A., Rojas, M.G. 2009. Some Organic Acids Acting as Stimulants of Recruitment and Feeding for the Formosan Subterranean Termite (Isoptera: Rhinotermitidae). Sociobiology. 54 (3):861-871.

Interpretive Summary: The Formosan subterranean termite is one of the most destructive and economically important urban pests in the United States. The use of baits is one of the most effective methods of control against this pest. This study provides information on the feeding stimulating activity of some organic acids. We discover that low concentrations of some organic acids found in decomposing wood and a blend of 2 of these organic acids with uric acid and glucosamine act to stimulate Formosan termites to feed and group around a bait mix. The importance of this discovery is that existing bait formulations can be significantly improved by the addition of small concentrations of these compounds. By stimulating feeding, termites take larger doses of toxic active ingredients mixed in the bait formulation thereby improving the effectiveness of the bait against this pest.

Technical Abstract: The feeding stimulating properties of 3 organic acids (salicylic, oxalic, and glucuronic acids) and 2 nitrogen containing compounds (uric acid, and glucosamine) for the Formosan subterranean termite were tested. A two choice test between cellulosic matrices with the compounds and blanks showed that Coptotermes formosanus Shiraki significantly preferred matrices with 50 ppm of oxalic acid, salicylic acid, or a blend of equal parts of these 2 compounds plus uric acid and glucosamine. Uric acid and glucosamine did not stimulate feeding or recruitment when added alone at concentrations of 50 ppm. The blend of 4 compounds including oxalic, salicylic, and uric acids and glucosamine was most effective stimulating feeding of C. formosanus at concentrations of 50 and 200 ppm, but the blend became feeding deterrent at 400 ppm. Glucoronic acid induced feeding stimulation at 450 ppm, but it induced feeding deterrence at 675 ppm. Results indicate that the feeding stimulating properties of these organic acids occur between narrow ranges of concentrations, which may differ significantly among different organic acids.