Temporal efficacy of commercially available pheromone lures for monitoring Helicoverpa zea (Lepidoptera: Noctuidae).

The performance of commercially available corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), female sex pheromone lures that attract male moths from four different commercial vendors was evaluated to determine the duration of catch in the field. Lures were aged outdoors beneath Scentry Heliothis traps for a period of 0, 2, 4, 6, and 8 weeks before standardized field testing in New York and North Carolina. Scentry Heliothis traps baited with aged lures were monitored for male H. zea for 14 d across two independent replications in each state. Gas chromatography-mass spectrometry study (GC-MS) was used to quantify the release rates and residual pheromone content in the dispenser of 11-Z-hexadecenal (Z11-16Ald), the major pheromone compound, for a subset of field-aged lures. We found an unequal decline in H. zea attraction efficiency among commercial lure types (significant lure type × age interaction). Lure type and age were also related to trap capture (model main effects), which are two important factors when selecting lures and determining replacement intervals in the field. Release of pheromone over 24 h was significantly different among lure types. Notably, discrepancies between residual pheromone and actual emission rates in septa lure highlights the need for better commercial dispensers with longer longevity and higher pheromone controlled release. Results highlight clear differences in lure performance that could directly affect the probability of H. zea detection in the field. Impacts of these temporal emission differences may increase the frequency of lure replacement in field applications.