The response of Agriotes obscurus click beetles to pheromone and its impact on the acquisition of a fungal pathogen

Wireworms, the larval stage of click beetles, are a pest of many root crops, and are a challenge to control due to their long, subterranean life style and tolerance to chemical insecticides. An alternative approach is to target the adults. Pheromones have primarily been used as aggregants in attract-and-kill pest management tactics. However, pheromones can also alter insect movement and social interactions in other ways. I investigated whether female sex pheromone can enhance the primary transmission of the fungal pathogen Metarhizium brunneum Petch in Agriotes obscurus L. click beetles. Using video tracking, I found sex pheromone increases beetle activity regardless of season, and different light and air movement conditions. Heightened activity resulted in 58% more male-to-male contacts in a small arena. Although beetles picked up significant numbers of spores from contact with conspecifics, and an environment contaminated by conspecifics, pheromone did not enhance the level of infection obtained through these pathways.