Evaluating attractants to the rusty grain beetle, Cryptolestes ferrugineus (Stephens)(Coleoptera: Laemophloeidae)

The rusty grain beetle (RGB), Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae) is a serious pest of stored grain throughout the world.  The male produced aggregation pheromone for this species was described many years ago, but synthetic pheromones have not been used to date for any outdoor field studies with feral beetles.  This experiment focused on the response of this grain pest to synthetic aggregation pheromone (Cucujolide-II) and wheat in areas outside of grain storage facilities.  This experiment showed a statistically significant response to the synthetic aggregation pheromone Cucujolide-II when combined with wheat as opposed to wheat alone.  Two-choice bioassays were then conducted under laboratory conditions to determine what stored commodities RGBs are positively attracted to.  Studies so far show adult RGBs positively responded to adult RGBs feeding on rolled oats vs blank control (P-value=0.0086), crushed wheat vs blank control (P-value=0.0153) and somewhat to corn meal vs blank control (P-value=0.0662).  Other two-choice laboratory tests that studied responses of adult RGBs to oats, dog food, and synthetic pheromone at different doses yielded variable results.  In total, the current and future work on responses to semiochemicals will help to build our knowledge about attractants for this pest that will be helpful in future studies of flight and dispersal ecology in the rusty grain beetle.