Evaluation of organic strategies to control a new invasive pest, swede midge, Contarinia nasturtii (Diptera: Cecidomyiidae)

Evaluation of organic strategies to control a new invasive pest, swede midge, Contarinia nasturtii (Diptera: Cecidomyiidae)

Summary

The project team has met with four farmers in person to discuss their farming systems and constraints in managing swede midge. This year was particularly challenging for experimental logistics, because the heavy snows late in the season lead to flooding at our partner sites at the Intervale in early. Some areas were flooded at least five times. This affected our ability to conduct some of our early season experiments, and affected replanting. At the end of the season, Hurricane Irene destroyed the plots at the Intervale in Burlington, Vermont. This ended our field experiments.

Objectives/Performance Targets

1) Evaluate the use of row covers for early season crop protection (season 1 and 2)
We were unable to conduct this study because of early season flooding.
2) Conduct an organic insecticide trial for swede midge control
We collected data on this trial late in the season on fall broccoli.
3) Evaluate the field efficacy and application dosage of entomopathogenic nematodes for swede midge control
We were unable to conduct this study because we were planning to test the efficacy of nematodes after finding swede midge damage early in the season.

Accomplishments/Milestones

The Intervale is a crucial site because it was the only location in Vermont in 2010 that had swede midge. We had no idea that the weather would occur the way that it did.
We set out to the carry out all of the activities proposed in the grant. A research technician was hired to carry the activities out. Due to the disastrous year in terms of weather, we did not carry out an August field demonstration, because many of our experiments were not carried out.
Dr. Chen will be holding a workshop at the winter workshop at NOFA-VT. There, she will partner with extension faculty Ann Hazelrigg (VT), Jon Turmel (VT), and Ruth Hazzard (MA). She will discuss the research directions and educate growers and gardeners on the pest.
Dr. Chen also recently acquired a colony of swede midge from Dr. Anthony Shelton of Cornell University. With a colony, it will be feasible to conduct more detailed experiments on the insect.

Impacts and Contributions/Outcomes

Dr. Chen will be conducting outreach talks during the winter conference at NOFA-VT, and with the Vermont Vegetable and Berry Growers meeting. By working with partner farmers, the project team is gaining applicable knowledge on how to manage the pest. The partnering farmers have been very strongly engaged in the research, and look forward to a better field season next year.

Collaborators: