Soybean cyst nematode (SCN) is the greatest yield robbing disease of soybean production across the United States, and SCN continues to spread throughout North Dakota. Effective management strategies for SCN are available, but a 15-30% yield loss is common before above ground symptoms appear, making proactive identification and monitoring critical for two different reasons. First, soil sampling is the best way to initially detect SCN, this is increasingly important in the western, central, and northeastern parts of the state. Second, monitoring egg levels allows growers to evaluate how well their management tools are working and is increasingly important in the southeast and east central parts of the state. In 2013, the NDSC and NDSU developed a free-sampling-bag program for growers, in order to encourage growers to sample for SCN. Between 2013 and 2023, approximately 6,000 samples have been submitted by North Dakota producers using this program, with many more expected in 2024. Maps generated from the project have served as a highly leveraged tool to increase awareness of the expanding SCN problem in North Dakota. Further, we aim to conduct field evaluations for the level of resistance present in commercial soybean varieties for managing SCN levels and the capacity of the pathogen to reproduce during the growing season. This work will help to give up-to-date information on commercial resistance available in North Dakota. We propose to continue this sampling program in 2025, evaluate commercial resistance, update Extension materials on SCN, and disseminate results during winter meetings in 2025/26.

i. Provide SCN sampling bags to growers of North Dakota
ii. Develop updated SCN distribution map (limited resolution so no farms or growers can be identified) and develop Extension material for distribution at field days, meetings, and other events for continued awareness of this pathogen.
iii. Create an interactive SCN map that can bring greater awareness and transparency to the results from historical SCN sampling program.
iv. Evaluate commercial soybean varieties under high SCN environments

i. Growers will be provided with free sampling bags for their testing of SCN on their own farms.
ii. Distribution maps will be generated for the understanding of the current status of SCN prevalence in North Dakota.
iii. Interactive SCN maps will be developed using historical data.
iv. Growers will be provided with access to field data of commercial soybean varieties with SCN reproduction capacity.
v. Extension material describing SCN, the distribution, and management practices available will be updated and distributed at 2025-26 winter meetings.

By providing farmers with access to SCN sampling, testing, and mapping of the distribution/severity of the soybean cyst nematode (SCN) across North Dakota, our research equips farmers with vital information on the prevalence and severity of this pest in their own fields. Further, our evaluations of commercially available soybean varieties under high SCN pressure provide insights into the best options for minimizing SCN-related losses. Together, these efforts empower North Dakota farmers with the tools and knowledge to safeguard their soybean yields, ensuring the state's agricultural production against the threat of SCN.