Abstract: Andraca bipunctata Walker is a severe defoliator species in Chinese tea plantation. The larvae of A. bipunctata can eat all the tea leaves in case of severe attack, and cause a significant damage. In this study, the sex pheromone of mainland population was identified. The crude pheromone was extracted from abdominal tips of virgin females by n-hexane during their courtship peak period. The extracts were analyzed by gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). The electrophysiological activity of sex pheromone components was tested by electroantennogram (EAG), and the optimal dose of sex pheromone was determined by the field trapping test. Ultimately, the sex pheromone of A. bipunctata was used to monitor the population dynamics in Wuzhishan city of Hainan province. The GC-EAD analyses revealed only one component that elicited responses for the male moth antennae. Based on the mass spectrum, the component was identified as E11, E14-18Ald. The pheromone component was proved to be correctly identified by EAD tests and field trapping results. The data of field trapping show the dose dependent attraction of the pest, with the maximum attractiveness at 0.9 mg sex pheromone loaded on rubber septum lure. The results of population monitoring show that the sex pheromone was a promising tool for monitoring the pest population. It is clear that there were two generations of A. bipunctata in Wuzhishan city of Hainan Province from May to October, and the peak emergence of adult were 17 June and 27 August respectively. The results of this study provided a theoretical basis for the application of sex pheromones for attracting and killing or monitoring pest population in the main tea producing areas of China.

Key words: Andraca bipunctata, sex pheromone, identification, population monitoring