Combined use of cover crops and the entomopathogenic fungi Metarhizium brunneum to manage wireworm

Wireworms, the larval stage of click beetles (Coleoptera, Elateridae), have caused severe damage to potato crops across Canada and the globe, making them a major pest. Many of the insecticides used to manage wireworm populations are now banned due to their negative effect on both the environment and human health. The use of cover crops in combination with the entomopathogenic fungus, Metarhizium brunneum, is an effective alternative strategy in reducing wireworm populations. Recent reports indicate that certain cover crops can reduce wireworm population through natural compounds released by the growing plant (allelopathy) or after they are mulched into the soil (fumigants). This study will investigate whether brown mustard, buckwheat, sorghum Sudan grass and barley (control) in combination with Metarhizium brunneum, will reduce wireworm populations (Limonius agonus) in southwestern Ontario.