Reinvestigation of sex pheromone components and attractiveness of synthetic sex pheromone of the pink borer, Sesamia inferens Walker (Lepidoptera: Noctuidae) in Okinawa

Two EAG-active compounds were found in the solvent extract of abdominal tips of virgin females of the pink borer Sesamia inferens. They were identified as (Z)-11-hexadecenyl acetate (Z11-16:Ac) and (Z)-11-hexadecen-1-ol (Z11-16:OH) at ca. 60 ng and ca. 20 ng per female, respectively, by means of GC-MS analysis and chemical derivatization. In field tests, a 75: 25 blend of these compounds showed maximum attractions at 1.0 mg when loaded on rubber septa. The optimal dose appears to be between 1.0 and 2.0 mg/septum. Addition of a possible minor component; (Z)-11-hexadecenal, showed neither synergistic nor inhibitory effects. The trap catches with the 75:25 blend of Z11-16:Ac and Z11-16:OH at 1.0 mg/septum were greater than those with virgin females, but the difference was not significant. This indicates that the attractiveness of this blend is comparable with that of virgin females.