D3436: Evaluating the efficacy of biorational products on TSSM and predatory mites in high tunnels

High tunnels (HT) are a protected agriculture tool for specialty crop farmers. Cucumbers (Cucumis sativa L.) are well suited for HT production because their vertical growth pattern allows for space optimization and repeated flowering, offering multiple harvest opportunities. However, the twospotted spider mite (Tetranychus urticae Koch; TSSM) is one of the primary pests of cucumbers in HTs. TSSM often goes unnoticed by farmers until the damage is irreversible and the pest is difficult to control. Current recommendations are based on field or greenhouse production and rely on conventional miticides. However, more is needed to satisfy HT growers who wish to use organic pest management methods. Selecting the most efficacious and economical control methods for TSSM management in HT growing systems is difficult for growers because of the need for research-based evaluations in these unique growing environments. Here, we will present results from bioassays under laboratory conditions—first, the evaluation of the oviposition deterrence effect of eight biorational products (Azadirachtin, Bacterium Chromobacterium, Beauveria bassiana, Burkholderia spp., extract of neem oil, potassium salts of fatty acid, pyrethrin and water) on TSSM. Second, assessing the mortality effect of these biorational products on TSSM and predatory mites (Amblyseius andersoni, Neoseiulus californicus, Neoseiulus cucumeris, Neoseiulus fallacis, and Phytoseiulus persimilis) that may be combined in an IPM program. The information gained through this work can help growers select pesticides that reduce TSSM populations and minimize the impacts on predatory mites. This work contributes to the development of an IPM program for TSSM in high tunnel production.