Caste characteristics of cuticular hydrocarbon inOdontotermes formosanus (Shiraki)
Author of the article:YANG Jin-Jin1** JI Bao-Zhong1*** LIU Shu-Wen2*** ZHANG Xin-Wei1 WANG Li-Ping1ZHAO Zheng-Ping1 D
Author's Workplace：1. Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China; 2. The Administration Bureau of Dr. Sun Yat-sen’s Mausoleum, Nanjing 210014, China
Key Words：Odontotermes formosanus, cuticular hydrocarbon, non-reproductive, reproductive
Abstract： [Objectives] To explore the caste characteristics of cuticular hydrocarbons in Odontotermes formosanus. [Methods] Cuticular hydrocarbons of individuals of different castes and instars were analyzed using solid phase microextraction, gas chromatography and gas chromatography-mass spectrometry. [Results] The cuticular hydrocarbon of workers, soldiers, larvae and alates had the same 32 components; mainly n-alkanes, branched alkanes and alkenes etc. Changes in the amount of some components in non-reproductive individuals can be summarized as follows: In workers (both major and minor workers), 1-C19:1 was significantly lower than in larvae and soldiers. In major workers, C31 and C34 were significantly lower than in minor workers and larvae. In minor workers (living in the nest), 2,8,8-trimeC10 was significantly higher, and C16 and C18 significantly lower, than in other non-reproductive individuals. In soldiers, C14 was significantly lower, and 2-me-1-C19:1 higher, than in other non-reproductive individuals, and C31 and C34 were significantly lower than in minor workers and larvae. In 1st instar larvae, C16 was higher than in other non-reproductive individuals. In 2nd instar larvae, (E)-9-4-meC18 was higher than in other non-reproductive individuals. In 3rd instar larvae, 1-C19:1 and C44 were higher than in other non-reproductive individuals. Furthermore, in 1st, 2nd, and 3rd instar larvae, 3,3,6-trimeC10 and 2-me-(E)-7-C16:1 were higher, and 8-C17:1 was significantly lower, than in other non-reproductive individuals. There were significant differences in the amounts of the components C12, C14, C17, C31, 2,8,8-trimeC10, 8-ethylC15, 2,6-dimeC17, 8-C17:1, 1-C17:1, 1-C18:1 and 9-C19:1 between reproductive and non-reproductive individuals. [Conclusion] The cuticular hydrocarbons of different castes of O. formosanus have the same components, but the amounts of some components differed significantly among different castes. Cuticular hydrocarbons can be used as an important caste-recognition cue in O. formosanus. The cuticular hydrocarbons of different larval instars and workers of different developmental stages had distinctive compositions. The secretion of cuticular hydrocarbons changed with developmental stage.