Evaluating astigmatid mites as alternative diets for Orius laevigatus: Effects on life history parameters

Integrated pest management (IPM) in greenhouse cultivation has benefited significantly from the use of predators such as Orius laevigatus. This beneficial insect, a natural enemy of thrips, can feed on pollen, facilitating preventive releases in flowering crops. However, in the absence of quality pollen, a supplementary food source is required to facilitate establishment. This study compared the performance of different populations of O. laevigatus, including wild and commercial populations and selected strains adapted to suboptimal pollen diets (1POL and 2POL), all fed with various species of astigmatid mites, a more economical alternative to traditional foods like Ephestia kuehniella eggs and Artemia cysts. The selected strains of O. laevigatus exhibited higher survival during nymphal development and greater fecundity when fed astigmatid mites compared to commercial populations. Among the astigmatid mites, Acarus siro was the best-performing diet, supporting high survival and acceptable development; however, it did not match the fecundity obtained with Ephestia kuehniella eggs. Acarus siro therefore represents a cost-effective supplementary or maintenance food, particularly suitable for sustaining populations in crops and for reducing reliance on Ephestia , especially when using genetically selected O. laevigatus strains that show enhanced performance on suboptimal diets.