Abstract:  【Aim】 To observe the calling behavior and dynamic rhythm, and to identify the sex pheromone component of female moths of Sylepta derogata, so as to provide basis for the development of sex attractants and population forecast and green control of this pest insect. 【Methods】 The virgin female moths of S. derogata were placed individually in a plastic cup and their calling behavior was observed every half hour from 0.5 h before scotophase to 0.5 h after scotophase. The female sex pheromone glands were collected from virgin female moths during the peak calling period and extracted by hexane. The mchromatographic peaks of the active components of the sex pheromone gland extracts were analyzed by gas chromatography coupled with electroantennographic detection (GC-EAD), and the chemical structure information of the active components of the sex gland extracts was determined by GC coupled with mass spectrometry (GC-MS). 【Results】 The peak callingperiod of female moths of S. derogata was between the 4th and 7.5th hour into scotophase, and the 3-4 day-old female moths displayed the most active calling behavior. When female moths were calling, their antennae swinged from side to side, their wings vibrated rapidly, and the ovipositor kept extended. Two pheromone candidates, which could elicit strong EAG response of male moths, were detected in the extracts of the female sex pheromone glands by GC-EAD analysis, and the component with higher content was 10,12-16∶Ald detected by GC-MS and further identified as (10E,12Z)-10,12-hexadecadienal (E10,Z12-16∶Ald) by comparing the results of GC analysis between the pheromone gland extracts and the blend of synthetic standard compounds containing four 10,12-16∶Ald isoforms. Further EAG test showed that E10,Z12-16∶Ald could elicit a significant EAG response of male moths in a dose-dependent manner. 【Conclusions】 The 3-4-day-old female moths of S. derogata show the most active calling behavior, and the peak calling period of female moths is between the 4th and 7.5th hour into scotophase, and the major female sex pheromone component was identified as E10,Z12-16∶Ald, which needs to be confirmed by further field male trapping experiment.

Key words: Sylepta derogata, calling rhythm, sex pheromone, (10E,12Z)-10,12-hexadecadienal, sex attractant