Comparison of electroantennograms from female and male cabbage looper moths (Trichoplusia ni) of different ages and for various pheromone concentrations.

The electroantennogram (EAG) responses of both male and femaleTrichoplusia ni to two components of the female-released sex pheromone were determined over a range of concentrations of chemical and age of insect. The EAG was at a peak at a dose of 100 μg for both dodecyl acetate and (Z)-7-dodecenyl acetate (Z7-12∶OAc) for both sexes. The EAG responses varied with age of the insect. Responsiveness to both components was at a maximum at three days postemergence for males followed by a fairly rapid senescence, and for females it peaked at three days followed by a rapid senescence forZ7-12∶OAc but not for dodcecyl acetate.