Soybean Disease Loss Estimates from the United States and Ontario, Canada — 2025

Soybean diseases reduce yield in North America each year. The importance of these diseases varies annually as many factors influence which diseases have the greatest impact on yield. These factors can include environment, production practices, and variety susceptibility to disease. 

The current publication provides estimates of annual soybean yield losses due to soybean diseases for the 2025 season in the major soybean-producing areas of the United States and Ontario, Canada. Extension, university, USDA plant pathologists, and/or soybean specialists from each state and province provided the estimates. These reports accounted for 99.9 percent of total soybean production in the United States and all of Ontario's production in 2025. The estimated losses include those caused by foliar diseases, stem diseases, nematodes, seedling blights, and diseases of harvested grain. 

Disease loss estimates are gathered using several methods, including disease surveys, interactions with Extension, university, government, industry, and farmer representatives, and personal experience with disease losses. Estimation methods vary by state or province. 

Values for soybean disease losses are based on yield before estimated losses occurred for each state or province and are determined using the formula (harvested bushels/[{100 – percent estimated disease loss}/100]). Next, the formula ([percent loss/100] × yield before estimated loss) is used to determine bushels lost for each participating state or province. Additional information on yield and economic losses due to soybean diseases can be found at the CPN Field Crop Disease Loss Calculator. 

2025 Production and Conditions

The U.S. produced nearly 4.3 billion bushels of soybean in 2025, which is 35.9 million bushels less than the average of the previous five years (Figure 1). The number of U.S. acres planted to soybean in 2025 was the lowest since 2019. Ontario, Canada, produced 130.8 million bushels in 2025, which is 18.0 million bushels less than the previous five years. In general, 2025 saw near-normal rainfall and above-average temperatures across much of the soybean growing regions. However, from 1 May through 30 September, precipitation was highly dependent upon location (Figure 2). Many states received 10+ inches above normal precipitation, while several states received much less than normal. Temperatures were several degrees above normal across most soybean-growing states (Figure 3). The National Oceanic Atmospheric Administration reported record humidity and record high overnight temperatures from mid-June through late July in parts of the midwestern U.S.

2025 Disease Losses

In all, an estimated 4.8 percent (216.5 million bushels) of the potential soybean production in 2025 was lost due to disease across 29 soybean-producing U.S. states, and 4.5 percent (6.1 million bushels) of the total soybean production in 2025 was estimated to be lost due to disease in Ontario, Canada. Table 1 provides yield-loss estimates for specific diseases across the soybean production system in the U.S. and Ontario, Canada, and Figure 4 compares the proportions of losses caused by major diseases. The estimated 2025 losses from soybean disease in the U.S. are the third-lowest among 30 years of available data, with only 2022 and 2023 lower. In Ontario, the estimated 2025 yield losses were lower than losses from any of the previous 15 years (2010-2024). 

Red crown rot was estimated to have caused 7.7 million bushels of soybean yield losses in the U.S. in 2025 (Figure 5). Estimated losses from this disease increased substantially in 2025 compared to 2024, when losses were estimated at only 121,354 bushels. Yield losses from red crown rot occurred in five U.S. states, and were primarily driven by estimated losses in Illinois and, to a lesser extent, in Indiana. The greatest cause of estimated yield losses in 2025 was soybean cyst nematode. However, estimated losses from soybean cyst nematode in 2025 were the lowest reported out of 30 years of available data. Estimated losses caused by sudden death syndrome in 2025 were the greatest since 2014. Wet weather conditions may have impacted both of these diseases in 2025, as wet soils can reduce the ability of the soybean cyst nematode to reproduce but are conducive to sudden death syndrome development and toxin uptake.

Table 1. Estimated soybean yield losses from diseases in 29 soybean-producing states in the United States and Ontario, Canada, in 2025, are listed in order of the greatest to the least losses in each disease category.

¹Lance, spiral, sting, stubby root, and stunt; ²Soybean mosaic, soybean vein necrosis, and others.

Diseases in the Northern United States

The northern states in the U.S., which include Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Nebraska, New York, North Dakota, Ohio, Pennsylvania, South Dakota, and Wisconsin, accounted for 79.0 percent of the total estimated U.S. yield losses in 2025. Because a high percentage of U.S. soybean production occurs in the northern states, disease losses in these states greatly affect the overall importance of different diseases across the country (see Table 2). From 1996 through 2018, the average annual estimated losses due to disease in the northern U.S. was 348.0 million bushels; from 2019 through 2024, it was 169.3 million bushels. The trend of reduced estimated losses due to soybean diseases continues in 2025, with an estimated 171.0 million bushels lost. As in 2024, no foliar diseases ranked among the top yield-reducing diseases in 2025 for the northern region. 

Table 2. Estimated soybean yield losses due to the five most significant diseases in the northern states¹ in 2025.

¹Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Nebraska, New York, North Dakota, Ohio, Pennsylvania, South Dakota, and Wisconsin. 

Diseases in the Southern United States

Similar to what was observed in the previous three years, soybean cyst nematode and root-knot nematode caused the most estimated yield losses in 2025 in the southern U.S., which includes Alabama, Arkansas, Delaware, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia (see Table 3). The difference in estimated losses from soybean cyst nematode and root-knot nematode is the least it has ever been since separate data collection values for root-knot nematode began in 2011. 

Table 3. Estimated soybean yield losses due to the five most significant diseases in the southern states¹ in 2025.

¹Alabama, Arkansas, Delaware, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia.

Diseases in Ontario, Canada

Soybean cyst nematode, sudden death syndrome, and seedling diseases caused the greatest estimated yield loss in Ontario, Canada, in 2025, followed by Phytophthora root and stem rot and Sclerotinia stem rot (see Table 4). 

Table 4. Estimated soybean yield losses due to the five most significant diseases in Ontario, Canada, in 2025.

¹Seedling diseases and Phytophthora root and stem rot were estimated to have caused similar yield losses in Ontario, Canada, in 2025.

Disclaimer

The yield losses estimated in this publication were provided by members of the North Central Research and Extension Activity (NCERA) 137 Soybean Disease Committee and the Southern Soybean Disease Workers. The information in this publication is intended as a guide. The values in this publication are estimates and are not intended to be used as exact measurements of soybean yield losses due to plant diseases. However, these data provide valuable insight into the ranking of a given disease's importance within a production region (north or south) and across the entire production system. The most appropriate means available were used to estimate disease losses, and no liability resulting from the use of these estimates is assumed. 

Additional information on yield and economic losses due to soybean diseases can be found at the CPN Field Crop Disease Loss Calculator.

Acknowledgements

Data Compilers

Tom Allen, Mississippi State University; Daren Mueller, Iowa State University; and Adam Sisson, Iowa State University

Authors

Ed Sikora, Auburn University; Travis Faske, University of Arkansas; Alyssa Betts, University of Delaware; Nick Dufault and Zane Grabau, University of Florida; Bob Kemerait, University of Georgia; Boris Camiletti, University of Illinois; Darcy Telenko, Purdue University; Daren Mueller and Adam Sisson, Iowa State University; Rodrigo Onofre, Kansas State University; Carl Bradley, University of Kentucky; Boyd Padgett, Trey Price, and Tristan Watson, Louisiana State University; Marty Chilvers, Michigan State University; Dean Malvick, University of Minnesota; Tom Allen, Mississippi State University; Mandy Bish, University of Missouri; Dylan Mangel, University of Nebraska; Gary Bergstrom, Cornell University; LeAnn Lux, North Carolina State University; Febina Mathew and Wade Webster, North Dakota State University; Horacio Lopez-Nicora, The Ohio State University; Maira Duffeck, Oklahoma State University; Albert Tenuta, Ontario Ministry of Agriculture, Food and Agribusiness; Alyssa Collins, Paul Esker, and Greg Roth, Pennsylvania State University; John Mueller and Michael Plumblee, Clemson University; Madalyn Shires, South Dakota State University; Heather Kelly, University of Tennessee; Tom Isakeit, Texas A&M University; David Langston and Yuan Zeng, Virginia Tech; and Damon Smith, University of Wisconsin-Madison.

Reviewers

Alison Robertson, Iowa State University and Kiersten Wise, University of Kentucky.

Production data from the United States Department of Agriculture-National Agriculture Statistics Service, Farm Service Agency, Statistics Canada, and direct state representative communication when data was unavailable elsewhere. Climate information from the National Oceanic and Atmospheric Administration-National Center for Environmental Information and the Iowa Environmental Mesonet.

Iowa Environmental Mesonet. Automated Data Plotter. Plot #97. Accessed 27 January 2026.

 United States Department of Agriculture National Agricultural Statistics Service. Quick Stats Database. Accessed 3 and 5 February 2026.

United States Department of Agriculture Farm Service Agency. FSA Crop Acreage Data Reported to the FSA. Accessed 19 January 2026.

Statistics Canada. Table 32-10-0359-01 Estimated areas, yield, production, average farm price, and total farm value of principal field crops in metric and imperial units. Accessed 20 January & 4 March 2026.

Sponsors

The authors thank the United Soybean Board and the Grain Farmers of Ontario through the Sustainable Canadian Agricultural Partnership (Sustainable CAP), a federal-provincial territorial initiative, for their support. Support was also provided by State and Federal Funds appropriated to the State Land Grant Institutions of cooperating authors and the United States Department of Agriculture - National Institute of Food and Agriculture (USDA-NIFA).

How to cite: Sikora, E., Faske, T., Betts, A., Dufault, N., Grabau, Z., Kemerait, B., Camiletti, B., Telenko, D., Mueller, D., Sisson, A., Onofre, R., Bradley, C., Padgett, B., Price, T., Watson, T., Chilvers, M., Malvick, D., Allen, T., Bish, M., Mangel, D., Bergstrom, G., Lux, L., Mathew, F., Webster, W., Lopez-Nicora, H., Duffeck, M., Tenuta, A., Collins, A., Esker, P., Roth, G., Mueller, J., Plumblee, M., Shires, M., Kelly, H., Isakeit, T., Langston, D., Zeng, Y., Smith, D. 2026. Soybean Disease Loss Estimates from the United States and Ontario, Canada — 2025. Crop Protection Network. CPN-1018-25. doi.org/10.31274/cpn-20260306-0.