We will evaluate insecticides for management of pyrethroid resistant soybean aphids in eastern North Dakota. This research will provide soybean growers with unbiased research data on insecticide efficacy and needed performance data on the newer groups of insecticides (modes of action), such as Transform WG, Sivanto Prime and Sefina. The residual activity of each insecticide in field also will be determined as growers need to know how long different insecticide will work to control soybean aphids. Further, we plan to assess any impact on beneficial insects, like lady beetles, from insecticides tested. Growers are interested in more sustainable insecticides that are less toxic to beneficial insects. In summary, this research will improve management of pyrethroid resistant soybean aphids, and mitigate the development of soybean aphid resistance to other insecticides. By understanding which insecticides manage pyrethroid resistant soybean aphids, soybean yields can be maximized. We are evaluating a broad range of registered and any new experimental insecticides with different modes of action to optimize control as part of an Integrated Pest Management (IPM) strategy.

• 1) To evaluate different insecticides and modes of action for sustainable management of pyrethroid resistant soybean aphids and impacts on natural enemies.
• 2) To develop extension outreach material on soybean insect pests for the NDSC, growers, crop consultants, agronomists, extension agents/specialist and other stakeholders.

• Results will be disseminated in NDSC reports and trade magazines, NDSC podcasts, NDSU Extension Crop & Pest Report, and the Entomological Society of America peer-reviewed journal, Arthropod Management Tests.
• Results will be presented at soybean extension and commodity meetings and field days. Relevant information will be shared with neighboring states for improved information exchange on soybean insect pests.
• New information from this research will be put into soybean insect extension outreach materials.

Objective 1 - Insecticide resistance in populations of soybean aphids complicates control decisions for growers, and potentially increases costs due to poor control (spraying more than once) and in turn decreases net returns. Since economic aphid populations are known to cause significant yield losses of over 50% if not managed, growers need to know which insecticide products are the most cost effective against pyrethroid resistant soybean aphids, the length of product effectiveness in the field and impacts on natural enemies. The 2nd objective will provide soybean insect pest resources for use by the NDSC, soybean growers, NDSU Extension and other stakeholders.