Use of semiochemical-baited traps to monitor the range expansion of the invasive Sitona lineatus (Curculionidae: Coleoptera) and the presence of associated ground beetles

Abstract

Abstract The invasive pea leaf weevil, Sitona lineatus (Linnaeus) (Coleoptera: Curculionidae), damages field peas, Pisum sativum Linnaeus (Fabaceae), and faba beans, Vicia faba Linnaeus (Fabaceae), on the Canadian prairies. We used semiochemical-baited pitfall traps to monitor and detect S. lineatus range expansion and capture associated predaceous ground beetles (Coleoptera: Carabidae) in pulse-growing regions across Alberta. Traps captured male and female S. lineatus in all pulse-growing regions in the spring and fall, including a first record of S. lineatus in the Peace River region of northwestern Alberta. Pheromone-baited traps captured more weevils than unbaited traps did, and the addition of host plant volatiles did not increase the catch. More weevils were captured in traps in pea fields compared to in faba bean fields. Rubber septa lures released more pheromones and attracted a similar number or more weevils to traps than microcentrifuge tube lures did. Ground beetle capture was not affected by semiochemical baits targeting S. lineatus. Ground beetle diversity varied by region and collection period, but the most frequently collected species was Pterostichus melanarius, a potential predator of S. lineatus. This study shows that pitfall traps baited with rubber septa pheromone lures can be used to monitor new and expanding S. lineatus populations, as well as potential natural enemy communities.