Practice-based optimization of biological control against a new aphid genotype in bell pepper

Abstract: Aphid control remains a major challenge in greenhouse bell pepper production due
to rapid population growth, frequent reinfestation, and the remarkable adaptive capacity of
aphid populations, which facilitates the evolution of insecticide resistance and other adaptive
traits increasing. The green peach aphid (Myzus persicae) is of particular concern, as multiple insecticide-resistant genotypes have become widespread in north-western European greenhouse systems. In addition, farmers report that beside their insecticide-resistance, the M. persicae that are now infecting their greenhouses also exhibits enhanced reproductive capacity, increased production of winged individuals, and reduced susceptibility to both plant protection products and natural enemies. This study summarizes results of practice-based trials to optimize biological control strategies against the M. persicae population currently prevalent in Flemish greenhouses, which growers report to exhibit altered behaviour and to be more difficult to control. Results demonstrated that improving early establishment of beneficial insects significantly enhanced predator establishment and delayed aphid population growth. These findings support a shift towards more targeted, efficient and economically sustainable biological control programs in greenhouse pepper production.