Trail-following activity of the fungus garden materials to Odontotermes formosanus ( Isoptera: Termitidae) foragers

• 1、Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry,Nanjing Forestry University, Nanjing 210037
• 2、The Administration Bureau of Dr. Sun Yat-sen’s Mausoleum, Nanjing 210014

Abstract：Odontotermes formosanus is an important fungus-growing termite. In this paper, we investigated trail-following activity of extracts of fungus garden, trunk's outer epidermis of Liriodendron chinense× L. tulipifera and the pine wood powder infected by Gloeophyllum trabeum (PWG) to O. formosanus foragers. Trail-following response rate and selection coefficient of different materials were tested by using streak method. Tested materials included the top layer of fungus garden in main chamber (TFM), the middle layer of fungus garden in main chamber (MFM), the bottom layer of fungus garden in main chamber (BFM), the fungus garden in satellite chamber (FSC). Based on the result, the best reagent was determined. Furthermore, trail-following activities were compared between extraction from the fungus garden, TEL and PWG. Moreover, the concentration effects of extraction of fungus garden on the trail-following activity was also studied. The n-hexane extraction showed the highest trail-following activity to O. formosanus foragers, those resulting from ethyl alcohol, acetone and ethyl acetate varied irregularly, and that of distilled water extraction was of the lowest one. BFM has the highest trail-following activity among all tested fungus garden materials, so it is the best for extraction. The linear relationship between the concentration of n-hexane extracting solution(X) and trail-following response rate (Y) can be expressed by the equation y = 1.6958x3 - 13.346x2 + 30.137x + 33.409. The fungus garden in the chambers of O. formosanus has obviously trail-following activity to its foragers. The trail-following activity of fungus garden was much higher than that of field-collected materials (TEL) and similar with that of PWG. BFM showed the highest trail-following activity, TFM second, MFM and FSC were lowest, but even so there were not significant differences between them. As to the extraction of trail-following substances, the n-hexane was the best reagent. The active concentration range of n-hexane extraction to O. formosanus foragers was 0.125 CU-1.00 CU.

Keywords： Odontotermes formosanus fungus garden symbiotic fungus foragers trail-following activity