Application of the natural phagostimulant hydroquinone in bait systems for termite management (Isoptera)

Hydroquinone is a phagostimulating pheromone found in labial glands of most, if not all, termite species. In this study, we investigated whether hydroquinone enhances the effectiveness of bait systems for termite control. Laboratory feeding choice tests on filter paper with Mastotermes darwiniensis Froggatt and Coptotermes acinaciformis (Froggatt) demonstrated that several compounds chemically related to hydroquinone had a phagostimulating effect, but none as strong as the natural pheromone. Hydroquinone also works as short-distance attractant: termites were lured towards a source of hydroquinone over a distance of several centimeters. In long-term laboratory choice feeding tests, M. darwintensis and C. acinaciformis consumed significantly more wood within three days and one week, respectively, if hydroquinone had been applied. The preference had diminished after four weeks. Addition of glucose or amino acids did not increase the phagostimulating effect of hydroquinone. In field tests, hydroquinone proved to be comparatively stable under natural conditions: after four weeks in the soil, ca. 30% of the original amount of hydroquinone was still left in the baits. In field baiting trials with colonies of M. darwiniensis, C. acinaciformis, and C. lacteus in Australia, hydroquinone significantly increased feeding and the number of termites in treated baits compared to controls. Preliminary field trials with 10 further termite species in Australia and overseas confirmed these results