2015
Improving soybean insect management
Contributor/Checkoff:
Category:
Sustainable Production
Keywords:
Biotic stressCrop protectionField management Pest
Lead Principal Investigator:
Erin Hodgson, Iowa State University
Co-Principal Investigators:
Project Code:
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:

This practical entomology project has resulted in generating information that has been the basis of several Extension publications, workshop presentations, videos and technical publication on the management of soybean aphids and spider mites. The goal of this continuing research is to protect soybean yields by optimizing productivity and improving pest management strategies. This work evaluates existing and emerging insect suppression tactics, like insecticides and host plant resistance, to protect yield and develop a suitable management plan. Insecticides are evaluated and research findings will be communicated to Iowa soybean growers as part of the extension educational program.

Key Benefactors:
farmers, agronomists, Extension agents

Information And Results
Final Project Results

During 2013-2015, two field locations were established each year. Plots were set up in a randomized complete block design with four replications, including different foliar insecticides, insecticidal seed treatments and host plant resistance. Soybean aphids were sampled weekly and an estimate of seasonal exposure was estimated for each treatment. Yield was also evaluated for each treatment.

Results of the 3-year study:
• Foliar insecticides labeled for soybean aphid were efficacious; meaning they all had good knockdown or killing power.
• Insecticidal seed treatments could reduce cumulative aphid days, but did not offer sufficient yield protection compared to foliar insecticides.
• Host plant resistance did reduce cumulative aphid days and were comparable to foliar insecticides in yield protection; however, yield potential of host plant resistant varieties was lower compared to susceptible soybean varieties.

Conclusions of the 3-year study:
• Farmers have a wide range of foliar insecticides to choose from if they need to protect yield from a soybean aphid outbreak.
• Scouting and timely treatment with foliar insecticides is recommended over the use of prophylactic seed treatments.
• Using host plant resistance dramatically decreases the likelihood a foliar insecticide will be needed to protect yield.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.