Submitted to: Journal of Stored Products Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/2/2012
Publication Date: 9/14/2012
Citation: Campbell, J.F. 2012. Attraction of walking Tribolium castaneum adults to traps. Journal of Stored Products Research. 51: 11-22. doi: http://dx.doi.org/10.1016/j.jspr.2012.06.002. Interpretive Summary: The red flour beetle is a major pest of food processing facilities' and its activity can be monitored using traps baited with pheromone and food odor attractants. How well these attractants work under real world conditions has not been previously evaluated, although anecdotal reports from users suggest that beetles are not highly responsive. Using a new experimental protocol that simulates how beetles interact with traps in commercial food facilities, it was demonstrated that beetle response was strongest to traps baited with pheromone and food attractant, or with pheromone alone, when air flowed from the trap toward the beetle. The beetle’s positive response to pheromone and food attractant baited traps extended out to a distance of 35 inches, the maximum distance tested. However, under still air conditions beetles did not respond to any of the tested attractants. Within food processing facilities, traps are often placed in sheltered locations with limited air movement, with the result that traps may have limited attractiveness to red flour beetles. Understanding the role of air movement on the response of this important pest could improve the interpretation of monitoring programs and guide the optimal placement of traps within a facility.
Technical Abstract: The red flour beetle, Tribolium castaneum (Herbst), is a major pest of food processing facilities and can be monitored using pitfall type traps. To determine how beetles interact with these traps under field situations, the behavior of individual beetles released in the vicinity of traps was observed in a large arena. Specifically, the response of adults to traps baited with combinations of commercially available pheromone and kairomone attractants was measured, as was the influence of beetle sex and strain, airflow presence or absence, and distance from trap. The beetle’s response to traps was strongest (e.g., more encountered trap, more remained in observation zone, more time was spent on treatment side, and decreased speed and increased turn angle) to pheromone/kairomone or pheromone baited traps when there was air movement, while kairomone alone and all attractants under still air conditions generated no significant response by the beetles. Even with the best combination of attractants and with airflow, average number encountering trap was only 40%. With airflow, beetles were successful at locating a pheromone/kairomone baited trap out to 90 cm, the maximum distance tested, but under still air conditions even at 10 cm there was no difference between traps with and without attractants. Since airflow at trap locations within commercial food facilities can vary considerably, these patterns of response to traps could significant impact insect detection.