Interpreting the relationship between pheromone component emission from commercial lures and captures of Helicoverpa zea (Boddie) in bucket and cone traps

Male corn earworm moths, Helicoverpa tea (Boddie), were captured in conical Texas pheromone traps (cone traps) and bucket traps baited with four diffe rent commercial lures manufactured by three different manufacturers. Becaus e significant numbers were captured in bucket traps baited with some of the lures, and none with others, the volatile emissions from all of the lures were sampled and analyzed by gas chromatographic methods. The numbers of ma les captured in two types of trap were compared with bait emissions in an e ndeavor to define a more effective lure for bucket traps. The lure from one manufacturer captured the same numbers of males in both trap types; one ca ptured more in bucket traps than in cone traps, and another captured only a small number in bucket traps. The emission rate of all active compounds fr om each of the different lures was approximately linear for the duration of the assays. A gas-liquid chromatographic peak associated with a third comp ound, ((Z) under bar)-9-tetradecenal, which reduces behavioral responses, w as observed in the emissions from all lures evaluated. The effectiveness of the Hereon (Emmigsville, PA) lure in capturing males in both types of trap was associated with a lower emission of ((Z) under bar)-11-hexadecenal, (( Z) under bar)-9-hexadecenal and ((Z) under bar)-9-tetradecenal than from th e other lures.