Developing native biocontrol agents: Life histories of predatory mirids Dicyphus famelicus and Dicyphus discrepans on common North American greenhouse plants

• In North America, Dicyphus famelicus and D. discrepans have biocontrol potential. • Both survive and reproduce on tomato when prey are present. • Without prey, D. famelicus lifespan is short and cannot reproduce. • Dicyphus famelicus also reproduces on strawberry and mullein when prey are present. Greenhouse crop production is an important and growing component of Canada’s horticultural sector, ensuring year-round food availability. Arthropod pest management in these protected environments is a continuous challenge. While biological control is often employed as a first response, new agents are needed to mitigate pressure from multiple pest species in diverse crops. In this study, we examined the life histories of two native generalist predatory insects, Dicyphus discrepans and Dicyphus famelicus (Hemiptera: Miridae), as a first step towards their development as greenhouse biocontrol agents. We measured developmental time, longevity, and fecundity of both species on tomato, with eggs of the Mediterranean flour moth Ephestia kuehniella (Lepidoptera: Pyralidae) provided as a dietary supplement . Additionally, we measured longevity and fecundity of D. famelicus on strawberry with E. kuehniella eggs, as well as on tomato leaflets and mullein (a potential banker plant) with and without E. kuehniella eggs. Dicyphus famelicus reached adulthood after 45 days and five instars, while D. discrepans matured after 41 days and four instars. Provisional prey increased D. famelicus longevity on tomato by ∼900% (+109 days) in males and ∼500% (+60 days) in females, and was necessary for reproduction. Dicyphus famelicus persisted on mullein albeit with reduced male lifespan and required prey to reproduce. Dicyphus famelicus also persisted on strawberry with prey. Overall, the ability of these mirids to establish on various plant species in the presence of prey shows promise for their biocontrol potential on greenhouse crops.