Abstract: [Objective] To provide references for the further study of feeding habits of workers and the exploitation of baiting techniques, we investigated the foraging behavior of Odontotermes formosanus (Shiraki) workers to the Pinus massoniana wood powder and the wood powder infected by Gloeophyllum trabeum and the attractive activity of the P. massoniana wood powder infected by G. trabeum to workers. [Method] A feeding device of O. formosanus was constructed by using Y-tube olfactometer as the main part and then foraging behavior of workers was observed. The selective preference of workers to the different wood powder was observed by using Y-tube olfactometer. [Result] The foraging behavior of the workers mainly consists of olfactory reception, exploration and identification of the food, and recruiting other foragers in the feeding device of Y-tube olfactometer. The foraging behavior to the pine wood powder with or without infection by G. trabeum was quite similar, but there were some differences in the time of different behavior processes. The workers appearance, access to the food, and mud shelter appearance in the arm of the pine wood powder were later than those in the arm of the wood powder infected by G. trabeum. The feeding behavior of workers collected from different host trees was ranked in responses as the following order: workers from Liriodendron chinense× L. tulipifera > those from Cinnamomum camphora > those from Metasequoia glyptostroboides. The foragers from different host trees all had two rush hours during the course of foraging in the arm filled with the pine wood powder infected by G. trabeum, but there were some differences in the timing of rush hour. The feeding activity of workers collected from L. chinense × L. tulipifera forest peaked at 0.5-1.5 h and 11.5 h, the workers from C. camphora at 3.5-5.5 h and 12.5 h, and the workers from M. glyptostroboides feed food only at 0.5-5.5 h and 10.5-13.5 h. By contrast, there was no peak in the feeding process of workers to the pine wood powder. The number of foragers visiting the pine wood powder infested by G. trabeum was much more than that visiting the pine wood powder. The selective preferences of workers between the pine wood powder and the wood powder infected by G. trabeum were compared. The workers from different forests all had strong preference to the pine powder infected by G. trabeum. [Conclusion] The studies on the foraging behavior demonstrated that the olfactory sensation played an important role in foraging process of O. formosanus or other cryptic foraging termites. The feeding memory of workers affected foraging behavior, but the degree of performance varied with the original food. The experimental results of termite selection preferences showed that the pine wood powder infested by G. trabeum was of obvious attractive activity to the foraging workers. In other words, there would exist some attractive activity substances in the pine wood powder infested by G. trabeum. The chemical composition of attractive activity substance and the olfactory recept mechanism of workers may be an interesting topic for further research.

Key words: Odontotermes formosanus (Shiraki), foraging behavior, wood powder of Pinus massoniana, pine wood powder infected by Gloeophyllum trabeum, attractive activity