Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2011
Publication Date: 8/15/2011
Citation: Duehl, A.J., Cohnstaedt, L.W., Arbogast, R.T., Teal, P.E. 2011. Evaluating light attraction to increase trap efficiency for Tribolium castaneum (Coleoptera: Tenebrionidae). Journal of Economic Entomology. 104(4):1430-1435.
Interpretive Summary: The red flour beetle is the most important insect pest in flour mills. Current trapping systems attract beetles through food and pheromone lures. This combination is more attractive than control traps but limited in its effectiveness. To better sample insects in flour mills and decrease the use of methyl bromide fumigation better traps are required. Scientists at the Center for Medical, Agricultural and Veterinary Entomology, ARS, USDA in Gainesville, FL, identified specific light spectra that are most attractive to the beetle. These wavelengths are in the near UV and when emitted by LEDs can be easily added to traps. The response to this wavelength was established in the lab but then tested in sheds. Traps with light captured 20 times the number of beetles compared to control traps in competitive shed trapping experiments where both traps had standard chemical baits. By adding visual cues to traps, trap efficiency can be greatly increased. This research identified a prime visual cue for these pest insects. Using more efficient light traps, beetles can be effectively sampled at lower densities and control efforts can be targeted at specific locations and times. With better sanitation and pest management, fumigations can be limited or even eliminated.
Technical Abstract: The red flour beetle, Tribolium castaneum (Herbst) is a major coleopteran pest in flour mills and storage facilities. An aggregation pheromone has been identified for this pest, however the pheromone is of limited value for population monitoring. To develop more efficient methods to monitor this pest experiments were conducted to determine if light functioned as an attractant for the red flour beetle. Light emitting diodes (LEDs) of various wavelengths were examined as light sources because they produce bright, narrow light spectra. A comparison of responses to light spectra across the visible and UV regions of the electromagnetic spectrum indicated that the beetle was most attracted to near UV light at a 390 nm dominant wavelength. The use of LEDs in laboratory experiments resulted in the capture 20% of the beetles released, compared to a 1% capture with the aggregation pheromone alone. Even more beetles were captured with a combination of LEDs and commercially available chemical lures in traps. LEDs can easily be added onto existing trap designs or new traps can be designed to take full advantage of positive phototaxis.