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ARS Home » Pacific West Area » Corvallis, Oregon » Horticultural Crops Disease and Pest Management Research Unit » Research » Research Project #442205

Research Project: On-Farm Integration of Organic Management of Spotted-Wing Drosophila in Fruit Crops

Location: Horticultural Crops Disease and Pest Management Research Unit

Project Number: 2072-22000-044-033-R
Project Type: Reimbursable Cooperative Agreement

Start Date: Oct 1, 2022
End Date: Aug 31, 2025

Objective 1. Development and expansion of monitoring and economic-based decision aids for organic agriculture. Obj. 1.1. Optimize sampling method for monitoring of adult and SWD larva. Obj. 1.2. Assess economic impacts of organically-approved IPM focused control strategies. Objective 2. Promote beneficial insects in organic fields. Obj. 2.1. Optimize methods for the release and quantifying establishment of G. brasiliensis. Obj. 2.2. Determine the impact of sustainable SWD management of natural enemies and pollinators Objective 3. Develop an integrated outreach and training to implement organic SWD management strategies. Obj. 3.1. Integrated outreach program to deliver outputs to organic growers. Obj. 3.2. Building an organic literate extension workforce through a project-specific Research and Extension Experiences for Undergraduates.

Imported wasps will be released in 8 x 85 m hoop houses with raspberry and blackberry or in open blueberry fields. Weekly releases of 200 wasps will be made on one end with non-crop habitat since the parasitoid can reproduce on SWD hosts there. Four release and four control sites will be set up. Each week, parasitism, adult SWD abundance, SWD larval infestation, natural enemy abundance and pollinator presence will be monitored in a transect to document the distance the parasitoid travels: 0, 10, 25, 50, 100 m away from release spot. Parasitism is monitored in sentinel traps with late-stage SWD larvae inside diet cups. These cups are covered with a mesh that prevents SWD adult movement, but allows parasitoids to enter. Cups are protected in a white delta trap and hung on the canopy. Adults are monitored by baited traps, and larval infestations are checked by collecting 1 kg fruit and salt-floating larvae from crushed fruit. Natural enemies will be monitored by shaking the canopy over a beat sheet for visual counts. Pollinators will be recorded with 5-min visual scans. Releases and monitoring will continue until fruit harvest. The number of adults trapped, larvae in fruit, and proportion of SWD pupae parasitized will be analyzed separately as response variables in a GLMM with repeated measures. Treatment, week, and treatment*week interactions will be fixed effects, and hoop house/plot will be a random subject effect using a Poisson or binomial distribution. The field trial will be repeated or adjusted as needed in a second year.