Influence of Age and Mating Status on Pheromone Production in a Powderpost Beetle Lyctus africanus (Coleoptera: Lyctinae)

SIMPLE SUMMARY: Powderpost beetles, such as Lyctus africanus, are a common pest group for dried cured wood. The damage is slow and inconspicuous; thus, the infestation is mostly identified belatedly due to a lack of knowledge of how to locate and monitor it. L. africanus produces a pheromone, a chemical compound to attract other beetles. This pheromone has been determined and suggested as a monitoring tool for L. africanus. Here, we examined the physiological and behavioral parameters that affect pheromone production. We found that food availability may affect pheromone production in adult L. africanus males. In addition, of three components in male L. africanus aggregation pheromones, major compounds 2 (3-pentyl dodecanoate) and 3 (3-pentyl tetradecanoate) may be affected by age, not mating status, while compound 1 (2-propyl dodecanoate) was produced steadily and was affected by mating status. This suggests compounds 2 and 3 might have an important function in aggregation behavior, especially in signaling for mating opportunities. We also were able to clarify the minor effect of compound 1 in the aggregation pheromone of L. africanus, although not its role. The present information will be helpful in understanding the chemical communication of these insects, which may be important for the development of improved pheromone-based management strategies for controlling Lyctus beetles. ABSTRACT: Powderpost beetles such as Lyctus africanus are a common pest group for dried cured wood, causing significant harm to wood and wood products. We examined the life span and effects of aging and mating status on pheromone production in the powderpost beetle L. africanus (Coleoptera: Lyctinae). Experiments compared starved and unstarved male groups, and chemical analysis was used to determine factors affecting pheromone production. Regarding lifespan, male beetles provided food survived up to 14 weeks, while starved beetles died before the fifth week. Thus, an adult L. africanus male may require food throughout its lifespan, and food availability may affect pheromone production. There was no significant difference in the quantity of two major pheromone compounds, compound 2 (3-pentyl dodecanoate) and 3 (3-pentyl tetradecanoate) between mated and un-mated males. On the other hand, a minor compound, compound 1 (2-propyl dodecanoate) showed increased quantity after mating. The two major compounds were produced in low amounts by young L. africanus beetles, increasing until the fifth week, and beginning to decrease at the ninth week. The minor compound was produced steadily without significant change up to 9 weeks. Our results represent a step forward in the knowledge of the chemical communication of this important pest.