Female sex pheromone of Athetis lepigone (Lepidoptera: Noctuidae): Identification and field evaluation

Athetis lepigone has been recorded in many countries in Europe and Asia, but it had never been documented as an agricultural pest until 2005. For the purpose of using the sex pheromone to control this pest, we conducted a study to identify the sex pheromone of A.lepigone by gas chromatography with an electroantennographic detector (GC-EAD) and GC coupled with mass spectrometry (GC/MS) analyses. Three pheromone candidates were detected by GC-EAD analysis in the extracts of the female sex pheromone gland, and two candidates were identified as (Z)-7-dodecenyl acetate (Z7-12:OAc) and (Z)-9-tetradecenyl acetate (Z9-14:OAc) in a ratio of 1:5 by mass spectral analysis of natural pheromone components and dimethyl disulphide adducts. In the field male trapping test, the traps baited with the binary blend captured high number of males, while traps with single component hardly caught males, indicating that the two components are essential for the male attractiveness. In addition, the optimum ratios of Z7-12:OAc and Z9-14:OAc were determined as 3:7-7:3, and the best doses for the binary blend (at ratio of 3:7 between Z7-12:OAc and Z9-14:OAc) were 0.25-0.5mg/trap, based on the number of male catches. The identification of a highly attractive sex pheromone will help in developing efficient strategies for monitoring and control of A.lepigone.