Identification and evaluation of effective biological control agents in deep winter greenhouse crops in Eastern Canada

Abstract: This study proposes an Integrated Pest Management strategy for winter greenhouses maintained at 5 °C, where Myzus persicae aphids thrive. We compared the efficacy of biological control agents (Nabis americoferus, Micromus variegatus, Eupeodes americanus, and Anystis baccarum) and biopesticides and oils (Beauveria bassiana, mineral oil, canola oil, and insecticidal soap) in spinach crops. The predators N. americoferus, E. americanus and M. variegatus proved most effective, reducing populations by over 67 % compared to the control. The biopesticides and oils did not differ significantly from the control, likely due to cold temperatures. Our results indicate that a biological control strategy based on the introduction of cold-hardy predators at the first signs of infestation has the potential to control aphid populations in cold-greenhouse vegetable production.