D3058: Improving two-spotted spider mite management in high tunnel cucumbers

High tunnels (HT) are a protected agriculture tool used among small farmers. The popularity of HTs falls on the low cost of construction and increased profitability by extending the growing season and protecting crops against climatic conditions. Cucumber (Cucumis sativa L.) are well suited for HT production because of their vertical growth pattern allowing for space optimization and repeated flowering, offering multiple harvest opportunities. However, two-spotted spider mite (Tetranychus urticae Koch; TSSM) is one of the primary pests of cucumbers in HT. TSSM sucks essential plant nutrients from the leaves, causing yellowed, mottling symptoms, and eventual leaf death. TSSM often goes unnoticed by farmers until the damage is irreversible and the pest is difficult to control without insecticides, which are limited in high tunnels. Because there is inadequate knowledge of the TSSM behavior inside HTs, it is essential to evaluate the performance of this pest and possible management strategies. Here, we will present results from an experiment evaluating the susceptibility of different cucumber`s cultivars for high tunnel production. We also evaluated the efficacy of different biopesticides labeled for mite management in HT across Indiana. Cultivar susceptibility was evaluated by quantifying TSSM symptoms using the Horsfall-Barret scale in a RCB design. Biopesticides were applied per label recommendations in separate tunnels planted with a single variety of cucumber (cv. Corinto) and applied in a RCB design. The information gained through this work can help growers select varieties that minimize TSSM damage and biopesticides that are efficacious at controlling this damaging pest.