Both male and female attractants influence Colorado potato beetle crop colonization

Colorado potato beetle (Leptinotarsa decemlineata; Coleoptera: Chrysomelidae) is a widespread key pest of potatoes and other nightshade crops of the temperate northern hemisphere.  Its evolution of multiple pesticide resistance is a continuing threat if chemical control is relied upon for pest management.  An integrated approach including semiochemicals and other non-pesticidal tactics is essential to sustainable management. In addition to the known volatile aggregation pheromone produced by male adult beetles that is attractive to both females and males, there is also a yet-unidentified female-produced sex pheromone. Using caged "bait plants" in the field in Maryland, USA, we tested the attraction of male and female beetles to groups of male-only, female-only, larvae, and uninfested bait plants. Results of five field experiments demonstrate that the female-produced sex pheromone is as attractive to male beetles as is the male-produced aggregation pheromone, yet it is not at all attractive to females. To our knowledge this is the first demonstrated instance of a beetle species using bidirectional communication between males and females. Use of semiochemicals for monitoring and management of Colorado potato beetle should consider male-, female-, and plant-produced volatiles as important tools for pest manipulation in potato IPM.