Sex Pheromones of Noctuid Moths. 1. A Quantitative Bioassay for the Sex Pheromone of Trichoplusia ni (Lepidoptera: Noctuidae)1

Abstract
The sex pheromone of Trichoplusia ni (Hübner), the cabbage looper, was bioassayed by noting the number of males that started to vibrate their wings or fly after exposure to ether extracts of female abdomen tips. The procedure can be used to detect a concentration as low as that equivalent to 1×10-4 female. The sensitivity of this type of bioassay depends upon the effort taken to exclude males from extraneous contact with the pheromone.