Corn diseases cost farmers an estimated $13.8 billion USD from 2020 to 2023, according to a new multiyear analysis led by plant disease specialists from across the United States and Ontario, Canada. The study , published in Plant Health Progress , found that diseases reduced corn yields by an estimated 2.5 billion bushels during the 4-year period, highlighting the significant economic and production risks facing growers each season.
The research represents collaborative efforts of more than 40 plant pathologists representing 29 U.S. states and Ontario, Canada, evaluated disease impacts on corn grown across 375.1 million acres during the 2020–2023 growing seasons. The researchers estimated annual yield losses caused by 37 pathogens or pathogen groups, along with losses associated with grain contaminated by mycotoxins. Among all diseases evaluated, tar spot, Fusarium stalk rot, and plant-parasitic nematodes caused the greatest estimated losses. Overall annual losses varied widely by region and year, ranging from negligible levels in Texas in 2023 to a 15.8% yield loss in Michigan in 2021. Across all surveyed locations and years, diseases reduced corn yield by an average of 3.0%—or an estimated average economic loss of $37.76 per acre annually. These figures did not include the added costs growers often face for disease management tools such as seed treatments and foliar fungicide applications.
The study provides one of the most comprehensive recent assessments of corn disease losses in North America. More than 40 corn disease experts contributed data and estimates to the project, allowing researchers to compare disease impacts across a wide geographic area and multiple growing seasons.
“Tracking estimated disease impact over the years documents how corn threats change over time and can help direct limited resources to address difficult crop protection issues,” Alyssa Betts (Department of Plant and Soil Sciences, University of Delaware) said.
These findings can help guide disease management recommendations, research priorities, and breeding efforts aimed at improving disease resistance in corn hybrids. The data may also assist Extension educators, commodity organizations, government agencies, and the crop protection industry in identifying the diseases that pose the greatest risks to production. The results highlight the importance of continued monitoring and coordinated disease management efforts as disease pressures shift over time and new threats emerge in corn production systems.
The article is the latest in a larger series of disease loss summaries coordinated through the Crop Protection Network . Data from the most recent growing seasons and for additional crops such as soybean, wheat, and cotton can be viewed at the Crop Protection Network’s Field Crop Disease and Insect Loss Calculator .
The present article is the latest multiyear summary of corn disease data. Data for 2012–2015 and 2016–2019 can be found in two previous Plant Health Progress publications.
Read " Corn Yield Loss Estimates Due to Diseases in the United States and Ontario, Canada, from 2020 to 2023 " to learn more.
About Plant Health Progress
Plant Health Progress (PHP) , published by The American Phytopathological Society, is a peer-reviewed, multidisciplinary journal of applied plant health and crop protection. Established in 2000, PHP publishes new scientific information to enhance the health, management, and production of agricultural and horticultural crops of economic importance.
Plant Health Progress
Corn Yield Loss Estimates Due to Diseases in the United States and Ontario, Canada, from 2020 to 2023
2-Apr-2026
The author(s) declare no conflict of interest.