Soybean is a highly valuable crop in the North Central U.S., but it consistently faces threats from various pathogens, which are exacerbated by changing climate conditions like milder winters and increasingly humid seasonsa,b. These environmental shifts facilitate the emergence and spread of diseases such as frogeye leaf spot and white mold, previously considered rare in certain areas, and the introduction of new threats like red crown rot in states like Indiana, Illinois, and Kentucky. To maintain productivity, farmers have increased their use of inputs such as seed treatments, multiple foliar fungicide applications, and pushing maturity groups to name a few. However, these practices raise concerns about increased costs and the potential for developing resistant pathogen populations. Evaluating the impacts of both high-intensity and low-intensity disease management strategies is crucial to determine the most effective practices for optimal disease control, yield, and economic return under varying conditions.
The market has recently seen a surge in biological control products, including beneficial microbes like bacteria and fungi, which offer more sustainable alternatives to chemical controlsc. Despite their potential, the field efficacy and economic feasibility of these biological products in soybean production are not well-established, raising questions about their practical utility compared to traditional chemical products. Furthermore, recent survey results from Nebraska have revealed significant gaps in the current management practices, such as unexpectedly high fungicide application rates and limited knowledge of fungicide modes of actiond. These findings indicate a pressing need for enhanced educational outreach and research to refine disease management strategies and prevent the escalation of fungicide-resistant pathogens.
In response to these challenges, we propose a collaborative multi-state project to survey regional soybean farmers. This initiative aims to gather detailed insights into the current management practices and the decision-making processes influencing those practices. By directly engaging with farmers and crop consultants, we can identify prevalent misconceptions and knowledge gaps that affect the efficacy and sustainability of management resources like fungicides and resistance genes. The insights gained from this survey will inform targeted research and extension efforts, ultimately leading to more sustainable soybean production practices across the North Central region. This project will not only improve our understanding of current management techniques but also establish a foundation for future research and the development of new, effective disease management proposals.

Objective 1: Integrated Disease Management Efficacy and Economic Viability
1a. High- vs. Low-Intensity Management Trials
We will run three-year, multi-site field trials comparing “high-intensity” strategies (e.g., multiple fungicide applications, seed treatments, and manipulating maturity groups) against minimal or no treatment. Each site’s yield, disease incidence, and associated costs will be tracked to determine the conditions under which each management intensity optimizes ROI. By doing so, we aim to offer farmers tailored recommendations for profitable, environment-specific disease management.
1b. Uniform Fungicide Trials
Building on established efficacy protocols, participating co-PIs will annually evaluate new and existing fungicide products across multiple environments. These data will inform regional updates to fungicide efficacy tables and provide a robust foundation for practical recommendations. In addition, the uniform approach will help pinpoint product performance under emerging disease challenges.
1c. Economic Analysis of Fungicide Trials
We will collect historical uniform fungicide trial results alongside new data, performing an economic meta-analysis to map ROI across various locations and weather patterns. This effort will reveal which fungicides perform best under differing temperature, rainfall, and humidity conditions, yielding environment-specific guidance. Ultimately, these findings will complement Objective 1a by identifying where intensive fungicide use is financially advantageous.
Objective 2: Biologicals Uniform Fungicide Trials
2a. Evaluating Biological Controls for White Mold
Yearly multi-location trials will pit biological fungicides against a known, highly effective chemical control and an untreated check. Researchers will gauge both disease incidence and yield, running partial profit analyses to assess cost-effectiveness. This will clarify the viability of biological products for white mold under real-world conditions.
2b & 2c. Biological Seed Treatments (Oomycetes & SDS)
We will explore the efficacy of biological seed treatments against key pathogens—Phytophthora, Pythium (2b), and Fusarium virguliforme, the causal agent of sudden death syndrome (2c). Trials will be conducted at sites either inoculated with or naturally containing these pathogens, measuring stand counts, disease severity, and yield. Each product’s profitability will be evaluated, guiding farmers on whether and when biological seed treatments make economic sense.
Objective 3: Soybean Farmer Survey
We will develop a survey aimed at understanding how farmers choose disease management tactics. This includes measuring their familiarity with fungicide modes of action, adoption of biological products, cost considerations, and perceived risks or benefits. Survey results will illuminate how economic and social factors influence on-farm decisions, steering future Extension content and possibly shaping new research directions.
Objective 4: Extension Materials and Decision Tools
4a. Development of Extension Material
Each season, participating co-PIs will compile data from their trials, leading to updated or newly created efficacy tables for both chemical fungicides and biological products. These resources will be disseminated through Extension events, digital platforms, Soybean Research Information Network (SRIN), and the Crop Protection Network (CPN), ensuring farmers and agronomists have access to the latest findings on product performance and best practices.
4b. Creation of ROI Decision Tools
Leveraging economic insights from Objective 1c, we will build and host interactive calculators for key soybean diseases—initially white mold and frogeye leaf spot. By entering product costs, grain prices, and expected yields, farmers will receive rapid estimates of likely returns. Promoted through channels like SRIN, these tools will empower farmers to compare products more effectively and bolster profitable disease management decisions.

The first major deliverable from this project will be a comprehensive set of uniform field trial data and analyses. By comparing high- versus low-intensity management regimes (Objective 1a), we will collect annual and multi-year information on yield, disease severity, and economic outcomes across a wide variety of environments. Additionally, fungicide efficacy trials (Objectives 1b and 1c) will focus on product performance using both existing and emerging commercial fungicides, leading to a meta-analysis to pinpoint what conditions and products result in the greatest return on investment. These trials will also include testing new biological control products (Objective 2), measuring the stand establishment, disease suppression, and yield benefits of such treatments for white mold, oomycetes, and sudden death syndrome (SDS).
By synthesizing large datasets from multiple years and locations, the second key deliverable is the creation of user-friendly economic and return on investment (ROI) tools. From Objective 1c, the meta-analyses will highlight fungicide efficacy across diverse climatic and agronomic variables, building on results from the uniform field trials. These insights will lead to the creation of a new ROI calculator (Objective 4b), allowing farmers to enter local costs, grain prices, and projected yields to estimate the probability of profitable returns for specific management choices. As a result, soybean farmers will be equipped to make data-driven decisions and optimize input expenditure.
The third deliverable centers on the survey of soybean farmers disease management decisions (Objective 3). This regional survey will capture producers’ experiences with, and perspectives on, fungicide applications, biological products, and the economic and environmental considerations behind their choices. By analyzing responses on knowledge gaps, common misconceptions, and influences on decision-making, the project team can provide targeted recommendations for both future research and Extension outreach. The resulting data will serve as a baseline for understanding how real-world implementation compares to best practices identified through field trials.
Fourth, new and regularly updated Extension materials will directly translate project findings into accessible resources for growers and agribusiness professionals. Annual data from Objectives 1 and 2 will be condensed into user-friendly formats, such as updated efficacy tables for chemical and biological products. These tables will offer side-by-side comparisons of product performance on white mold, oomycetes, SDS, and other critical pathogens. The results will be distributed through winter meetings, field demonstrations, and partnerships with the Soybean Research and Information Network (SRIN) and the Crop Protection Network, ensuring that all stakeholders have timely access to the latest recommendations.
Fifth, project outcomes will appear in peer-reviewed scientific journals. These publications will extend the impact of the research with the broader scientific and agricultural community

Updated January 9, 2026:
Research Overview
Soybean production in the North Central US is increasingly threatened by pathogen pressures which can be exacerbated by shifting environmental conditions, including milder winters and warmer summer months. Diseases such as frogeye leaf spot and white mold are now common throughout much of the region, alongside emerging threats like red crown rot in the southern portion of the North Central region and the development of sudden death syndrome in the northern tier of the North Central region. In response, farmers have needed to adopt intensive disease management practices involving increased use of seed treatments with multiple modes of action, consistent and often multiple fungicide applications, and shifts in maturity groups. These practices, while potentially effective, raise concerns regarding higher production costs and the risk of developing fungicide-resistant pathogens. Therefore, there is a need to evaluate and optimize both high-intensity and low-intensity management practices to identify effective and economically viable approaches to disease control.
The surge in biological control products, including beneficial bacteria and fungi, presents promising sustainable alternatives to chemical controls. However, their practical efficacy and economic viability in soybean production remain uncertain due to a lack of standardized field data. Recent localized surveys from the University of Nebraska-Lincoln indicate significant gaps in current disease management practices, such as excessive fungicide use and limited understanding of fungicide modes of action. To address these challenges, this research proposes conducting multi-site trials to assess the effectiveness and return on investment (ROI) of varying fungicide trials. Further, economic analyses using historical and current trial data will further refine our understanding of conditions under which specific strategies result in the greatest economic returns.
Additionally, this project will conduct a survey of soybean farmers across the North Central region to identify and address knowledge gaps, management practices, and decision-making drivers. Insights gained from this survey will guide targeted Extension outreach and inform the development of effective educational materials and interactive decision-support tools. Further, tools from the previously discussed economic analyses will be incorporated into a new decision support system, which will assist farmers in making informed and economically beneficial decisions on disease management practices. Ultimately, this multi-state project aims to improve the productivity and profitability of soybean farming within the North Central region.
Objectives
Objective 1: Integrated disease management strategies, fungicide efficacy, and economic viability of these strategies will be evaluated across the North Central region.
Objective 1a: High-Intensity vs. Low-Intensity Uniform Disease Management Trials
Objective 1b: Uniform Fungicide Trials for Foliar Soybean Diseases
Objective 1c: Economic Analysis of Uniform Fungicide Trials

Objective 2: The efficacy of commercial biological control products will be evaluated for their reduction of soybean disease development.
Objective 2a: Biological Control Products for White Mold
Objectives 2b and 2c: Biological Control Seed Treatment Trials for Pythium/Phytophthora and Sudden Death Syndrome

Objective 3: A survey will be distributed to farmers across the North Central region to better understand the current farmer knowledge of soybean diseases and what is driving their disease management decisions.

Objective 4: Develop Extension material and interactive disease management decision tools
Objective 4a: Development of Extension Material
Objective 4b: Develop New Management Decision Tools

Completed Work and Objective Progress
Progress on the pathology led project has been moving forward steadily. At the beginning of the project in October of 2024, all seven PIs/co-PIs met in Madison, Wisconsin to plan for the next three years of the project. At this meeting, each co-PI presented the objective that they will be leading and their plans for completing each objective. Updates on each objective are listed below.

Objective 1.
Objective 1a. Field trials examining varying levels of soybean disease management are being led by Dr. Dylan Mangel from the University of Nebraska-Lincoln. Within these trials, there will be 8 treatments examined which will include the following. These will be focusing on combinations of seed treatment with foliar fungicide applications. Each combination of these will be explored exemplifying high intensity in management practices to low intensity.
Treatment Number Seed Treatment Foliar Application 1 Foliar Application 2
1 Non-treated - -
2 CruiserMaxx & Saltro Delaro Complete 8 floz/ac @ R1 Delaro Complete 8 floz/ac @ R3
3 CruiserMaxx & Saltro - Delaro Complete 8 floz/ac @ R3
4 CruiserMaxx & Saltro - -
5 - Delaro Complete 8 floz/ac @ R1 Delaro Complete 8 floz/ac @ R3
6 - - Delaro Complete 8 floz/ac @ R3
7 CruiserMaxx & Saltro Delaro Complete 8 floz/ac following Frogspotter -
8 - Delaro Complete 8 floz/ac following Frogspotter -

For this objective, 7 site-years will be conducted with one location in each of the seven representative states. Seed of these varieties have been sourced and are currently being treated at the University of Nebraska-Lincoln by the Mangel team. The seed will be distributed to each university within the next few weeks. Progress is moving smoothly with no barriers at this time.

Objective 1b. Field trials examining multiple soybean foliar fungicide programs will be led by Dr. Darcy Telenko of Purdue University. The treatments being tested are listed here.
Treatment Number Fungicide Program
1 Non-treated Control
2 Delaro Complete 8 floz/ac @ R3
3 Delaro Complete 8 floz/ac @ R5
4 Delaro Complete 8 floz/ac @ R3 & R5
5 Adastrio 8 floz/ac @ R3
6 Badge SC 1.5 pt/ac @ R3
7 Affiance 14 floz/ac @ R3
8 Generic Quilt (Tigris Azoxyprop) 12 floz/ac @ R3
9 Generic Quilt (Tigris Azoxyprop) 12 floz/ac @ R5
10 Viatude 16 floz/ac @ R3
These treatments will be examining multiple commercially available products that farmers are using across the region. Further, we are examining the use of generic products as well which would offer a more cost-effective option for farmers, if efficacy is not reduced. Lastly, we are examining the application of products at the R5 growth stage due to the lack of information available on this timing. This lack of information came to be known after Hurricane Helene moved through parts of Indiana and Ohio in 2024, leaving many soybean acres affected by fungal infections. As a result, it was questioned if later fungicide applications could have mediated these infections, and therefore we plan to evaluate these timings to acquire data for these later growth stages.
For this objective,10 site years will be conducted across the seven states. Currently, protocols have been distributed to all co-PIs, seed is being sourced, and trials will be planted shortly. Each PI is also working on sourcing fungicides from each company as well for evaluation. Progress is moving smoothly with no barriers at this time.

Objective 1c. A meta-analysis of historical white mold fungicide trials is currently underway and led by Dr. Damon Smith out of the University of Wisconsin-Madison. A dataset has been created and finalized with trial data dating from 2017-2024 across seven states. This dataset includes data looking at various commercially available fungicide products with varying application timings. To assist in the conducting of this analysis the Data Science Institute at the University of Wisconsin-Madison has been brought in for their expertise in examining the primary ANOVA tables from data of each individual field trial. From these ANOVA tables, we are currently working on conducting a weighted network meta-analysis from these results. It is expected that much progress will be made in the next 6 months of this project. Progress has been moving rapidly for this sub-objective which is ahead of schedule. We do not expect any barriers for this project in the near future.

Objective 2.
Objective 2a. White mold is caused by the fungal pathogen Sclerotinia sclerotiorum which forms long-term survival structures called sclerotia which survive in field soil. In this objective, management by commercial biological control agents will be investigated by field trials examining the application of products focused on the degradation of these sclerotia in the soil. This objective is co-led by Drs. Darcy Telenko, Damon Smith, and Wade Webster. Currently, sclerotia from S. sclerotiorum are being grown under laboratory conditions, and then these sclerotia will either be buried or placed on the surface of the soil within small mesh sample bags. These sclerotia will then have these biological products applied over the top and left fallow for an entire season. These trials will be conducted by using either Contans (active agent: Coniothyrium minitans), Theia (active agent: Bacillus subtilis strain AFS032321), and RootShield Plus (active agents: Trichoderma harzianum and T. virens). All of these species are biological agents with mycoparastism which are known to degrade fungal organisms such as S. sclerotiorum. At four time-points over 12 months these sclerotia will be recovered from the field and evaluated for degradation. To evaluate this degradation, the sclerotia will be plated onto potato dextrose agar growth media and observations will be made if fungal growth appears out of the sclerotia. It is expected that the biological control products will have varying degrees of degradation across the North Central region. We will also be collecting soil samples at the establishment of each trial to examine the soil texture and the levels of biological activity by using Solvita tests. This data will allow for us to better understand which soil conditions are more favorable for sclerotial degradation compared to others. These trials will be conducted across seven site years in the region during 2025.

Objective 2b. The evaluation of biological seed treatment products for the control of oomycete pathogens is being led by Dr. Wade Webster. A total of four biological products alongside two controls have been identified that are of interest to the group for control of these pathogens. These trials will be inoculated with either Pythium or Phytophthora for disease reduction or will be planted into fields with a history of soybean seedling diseases. The seed treatments in this study will include the following.
Treatment Number Fungicide Program
1 Non-treated Control
2 Base (CruiserMaxx) @1.38 floz/140,000 seeds
3 Base + RootShield Plus @ 2 lbs/140,000 seeds
4 Base + Terrasym 401 @ 0.125 oz per 140,000 seeds
5 RootShield Plus @ 2 lbs/140,000 seeds
6 Terrasym 401 @ 0.125 oz per 140,000 seeds

Further, we have added an additional component to this objective in an attempt to standardize vigor ratings. We have coordinated with Dr. Mark Licht from Iowa State University to help perform standardized drone imagery across these trials at the V2 growth stage in addition to on-ground validation of seedling height, biomass, and stand counts. This work will lead to the development of a standardized method of determining and measuring plant vigor for improved understanding of how these type of products impact overall soybean health. These trials will be conducted across 11 site years in the North Central region. Seed is being treated at Iowa State University and will be distributed to each state in early April for planting in the spring. Progress is moving smoothly with no barriers at this time.


Objective 2c. Biological control of SDS by seed treatments is being led by Dr. Daren Mueller at Iowa State University. A total of 6 seed treatments have been identified alongside controls. Trials will be conducted in fields naturally infested with SDS. These trials will be conducted across 8 site-years in 2025. Seed is being treated at Iowa State and will be distributed to each state in early April.
Treatment Number Fungicide Program
1 Non-treated Control
2 Base (CruiserMaxx) @1.38 floz/140,000 seeds
3 Base + CeraMax + Germate Plus
4 Base + Avodigen + Adaplan + Ethos Elite
5 Base + TBZ + Headsup + Biost 2nd Gen + Ascribe SAR
6 Base + RootShield Plus
7 Base + ILEVO

Objective 3. Farmer Survey
Dr. Horacio Lopez-Nicora has led discussions with a survey consultant company, called PRIME46, to initiate the development of this survey in the second quarter of 2025 to capture soybean farmers’ level of understanding of soybean disease impact and management decisions. The survey tool, including questionnaires, a list of participants, and inclusion-exclusion criteria, is currently under development. We expect the survey to be completed by the third quarter of 2025. Establishing this baseline will aid researchers and stakeholders in identifying critical knowledge gaps, ultimately enhancing the protection of soybean health. Progress of this objective is moving along smoothly, and we do not see any major barriers at this time.

Objective 4. The development of new Extension material has been progressing nicely. Through the Crop Protection Network, our group has been involved in the updating of publications as of the spring of 2025 including the ‘Fungicide Efficacy for Control of Soybean Foliar Diseases’, ‘Fungicide Efficacy for Control of Soybean Seedling Diseases’, and ‘Soybean Disease Loss Estimates from the United States and Ontario, Canada – 2024’. Further, new publications involving our team included the ‘Scouting for Soybean Stem Diseases’, ‘Monitoring for resistance to the SDHI fungicide seed treatments ILEVO (fluopyram) and Saltro (pydiflumetofen) for soybean sudden death syndrome (SDS ) management’. Also, a new CPN TV video was recently released titled ‘White Mold: Insights and Updates for 2025’ which was created by Drs. Chilvers, Smith, and Webster. During the year of 2024, a total of 67,892 page views were recorded for all soybean content, which is up from 27,000 in 2022 and 41,000 in 2023. Progress is moving smoothly with the development of new Extension material for the benefit of North Central soybean farmers and more content will be developed in the coming years of this project.

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Updated January 30, 2026:
Research Overview
Soybean production in the North Central U.S. is increasingly threatened by pathogen pressures which can be exacerbated by shifting environmental conditions, including milder winters and warmer summer months. Diseases such as frogeye leaf spot and white mold are now common throughout much of the region, alongside emerging threats like red crown rot in the southern portion of the North Central region and the development of sudden death syndrome in the northern tier of the North Central region. In response, farmers have needed to adopt intensive disease management practices involving increased use of seed treatments with multiple modes of action, consistent and often multiple fungicide applications, and shifts in maturity groups. These practices, while potentially effective, raise concerns regarding higher production costs and the risk of developing fungicide-resistant pathogens. Therefore, there is a need to evaluate and optimize both high-intensity and low-intensity management practices to identify effective and economically viable approaches to disease control.
The surge in biological control products, including beneficial bacteria and fungi, presents promising sustainable alternatives to chemical controls. However, their practical efficacy and economic viability in soybean production remain uncertain due to a lack of standardized field data. Recent localized surveys from the University of Nebraska-Lincoln indicate significant gaps in current disease management practices, such as excessive fungicide use and limited understanding of fungicide modes of action. To address these challenges, this research proposes conducting multi-site trials to assess the effectiveness and return on investment (ROI) of varying fungicide trials. Further, economic analyses using historical and current trial data will further refine our understanding of conditions under which specific strategies result in the greatest economic returns.
Additionally, this project will conduct a survey of soybean farmers across the North Central region to identify and address knowledge gaps, management practices, and decision-making drivers. Insights gained from this survey will guide targeted Extension outreach and inform the development of effective educational materials and interactive decision-support tools. Further, tools from the previously discussed economic analyses will be incorporated into a new decision support system, which will assist farmers in making informed and economically beneficial decisions on disease management practices. Ultimately, this multi-state project aims to improve the productivity and profitability of soybean farming within the North Central region.
Objectives
Objective 1: Integrated disease management strategies, fungicide efficacy, and economic viability of these strategies will be evaluated across the North Central region.
Objective 1a: High-Intensity vs. Low-Intensity Uniform Disease Management Trials
Objective 1b: Uniform Fungicide Trials for Foliar Soybean Diseases
Objective 1c: Economic Analysis of Uniform Fungicide Trials

Objective 2: The efficacy of commercial biological control products will be evaluated for their reduction of soybean disease development.
Objective 2a: Biological Control Products for White Mold
Objectives 2b and 2c: Biological Control Seed Treatment Trials for Pythium/Phytophthora and Sudden Death Syndrome

Objective 3: A survey will be distributed to farmers across the North Central region to better understand the current farmer knowledge of soybean diseases and what is driving their disease management decisions.

Objective 4: Develop Extension material and interactive disease management decision tools
Objective 4a: Development of Extension Material
Objective 4b: Develop New Management Decision Tools

Completed Work and Objective Progress
Progress in the first year of the pathology-led project has been moving forward steadily. At the beginning of the project in October of 2024, all seven PIs/co-PIs met in Madison, Wisconsin to plan for the next three years of the project. During the 2025 growing season, all trials were successfully conducted, and planning is currently underway to conduct trials during the 2026 growing season. Below are the progress updates for each objective within this project.
Objective 1.
Objective 1a. Field trials examining varying levels of soybean disease management are being led by Dr. Dylan Mangel from the University of Nebraska-Lincoln. Within these trials, there will be 8 treatments examined which will include the following. These will focus on combinations of seed treatment with foliar fungicide applications. Each combination of these will be explored, exemplifying high intensity in management practices to low intensity.
Treatment Number Seed Treatment Foliar Application 1 Foliar Application 2
1 Non-treated - -
2 CruiserMaxx & Saltro Delaro Complete 8 floz/ac @ R1 Delaro Complete 8 floz/ac @ R3
3 CruiserMaxx & Saltro - Delaro Complete 8 floz/ac @ R3
4 CruiserMaxx & Saltro - -
5 - Delaro Complete 8 floz/ac @ R1 Delaro Complete 8 floz/ac @ R3
6 - - Delaro Complete 8 floz/ac @ R3
7 CruiserMaxx & Saltro Delaro Complete 8 floz/ac following Frogspotter -

8 - Delaro Complete 8 floz/ac following Frogspotter -
During the 2025 field season, the first year of Objective 1A was conducted across six locations in the North Central region. Two of the eight planned locations were unable to conduct the trial this year, but plan to in 2026. With the exception of North Dakota, all locations used the variety GH2814E3S. All sites received the same base seed treatment of CruiserMaxx APX (4.18 fl oz/100 lbs) and Saltro (2.3 fl oz/100 lbs), while foliar fungicide applications consisted of Delaro Complete (8.0 fl oz/ac) applied with a non-ionic surfactant. Plant stand, disease severity, disease incidence, and yield components were collected and compared. Additionally, harvested seed was collected to observe and compare the occurrence of seed-borne disease. Preliminary analyses indicated no significant differences in yield or return on investment (ROI) among management intensities when averaged across locations. However, profitability and yield varied by site, highlighting the strong influence of environmental conditions on treatment response. Combining seed treatment with a single fungicide application, timed using a disease forecasting tool, was the most consistently profitable strategy across locations.

Objective 1b. Field trials examining multiple soybean foliar fungicide programs are led by Dr. Darcy Telenko of Purdue University. The treatments being tested are listed here.
Treatment Number Fungicide Program
1 Non-treated Control
2 Delaro Complete 8 floz/ac @ R3
3 Delaro Complete 8 floz/ac @ R5
4 Delaro Complete 8 floz/ac @ R3 & R5
5 Adastrio 8 floz/ac @ R3
6 Badge SC 1.5 pt/ac @ R3
7 Affiance 14 floz/ac @ R3
8 Generic Quilt (Tigris Azoxyprop) 12 floz/ac @ R3
9 Generic Quilt (Tigris Azoxyprop) 12 floz/ac @ R5
10 Viatude 16 floz/ac @ R3
During the 2025 field season, the first year of Objective 1B was conducted across twelve locations in the North Central region. These trials are being planned to be repeated in 2026. All sites. At each location, the development of foliar diseases was evaluated for the fungicide programs applied. These diseases include frogeye leaf spot, Cercospora leaf blight, and Septoria brown spot. At the end of the season, yield was collected at all sites adjusted to 13% moisture. Currently, all data is being aggregated across all twelve locations and being fed into larger historical datasets. These analyses are still being conducted.
Objective 1c. A meta-analysis of historical white mold fungicide trials was successfully performed under the direction of Dr. Damon Smith at the University of Wisconsin-Madison. This dataset included fungicide trial data from 2017-2024 across seven states in the North Central region. This dataset included field trial data examining the effects of various commercially available fungicide products with varying application timings. To assist in the conducting of this analysis the Data Science Institute at the University of Wisconsin-Madison had been brought in for their expertise in examining the primary ANOVA tables from data of each individual field trial. From these ANOVA tables, a weighted network meta-analysis was conducted. This work has been published as a PhytoFrontiers paper with all models disclosed. Using these results, Monte-Carlo simulations were performed and used to create a new White Mold ROI-Calculator that is now available on the Crop Protection Network. Farmers and practitioners can now access the tool and use it to make informed fungicide decisions based on economics.
• Renfroe-Becton, H., Oros, M., Byrne, A.M., Chilvers, M.I., Kleczewski, N., Lopez-Nicora, H.D., Mueller, B.D., Mueller, D.S., Smith, D.L., Telenko, D.E.P., and Webster, R.W. 2025. Meta-analytic and economic evaluation of fungicide programs applied for managing Sclerotinia stem rot in soybean across the north-central United States. PhytoFrontiers. https://doi.org/10.1094/PHYTOFR-07-25-0068-R.
• https://cropprotectionnetwork.org/roi-calculators
Objective 2.
Objective 2a. White mold is caused by the fungal pathogen Sclerotinia sclerotiorum which forms long-term survival structures called sclerotia which survive in field soil. In this objective, management by commercial biological control agents will be investigated by field trials examining the application of products focused on the degradation of these sclerotia in the soil. This objective is co-led by Drs. Darcy Telenko, Damon Smith, and Wade Webster.
During the 2025 field season, at least 6 field trials were conducted. These were performed by placing sclerotia into small mesh sample bags, and these were either buried or placed onto the soil surface. These sclerotia then had biological products applied over the top and left fallow for an entire season. These trials will be conducted by using either Contans (active agent: Coniothyrium minitans), Howler (active agent: Pseudomonas chlororaphis strain AFS009), and RootShield (active agents: Trichoderma harzianum). All of these species are biological agents with either inhibitory or mycoparasitic characteristics which are known to degrade fungal organisms such as S. sclerotiorum. At four time-points over 12 months, these sclerotia will be recovered from the field and evaluated for degradation. Three time points at 1, 2, and 3 months after establishment have already been collected. We will be collecting the final timepoint in April of 2026 as the final timepoint of evaluating degradation. To evaluate this degradation, the sclerotia were plated onto potato dextrose agar growth media, and observations will be made if fungal growth appears out of the sclerotia. It is expected that the biological control products will have varying degrees of degradation across the North Central region. This data has all been collected up to the third time-point, and we are waiting for the final time-point in April to be completed for us to evaluate the results with statistical analyses. These trials will be repeated for another season of testing in 2026.

Objective 2b. The evaluation of biological seed treatment products for the control of oomycete pathogens is being led by Dr. Wade Webster. A total of four biological products, alongside two controls, have been identified that are of interest to the group for control of these pathogens. These trials will be inoculated with either Pythium or Phytophthora for disease reduction or will be planted into fields with a history of soybean seedling diseases. The seed treatments in this study will include the following.
Treatment Number Fungicide Program
1 Non-treated Control
2 Base (CruiserMaxx) @1.38 floz/140,000 seeds
3 Base + Trianum P @ 0.5 oz/140,000 seeds
4 Base + Terrasym 401 @ 0.5 oz per 140,000 seeds
5 Trianum P @ 0.5 oz/140,000 seeds
6 Terrasym 401 @ 0.125 oz per 140,000 seeds
In the 2025 growing season, 15 locations were tested for this study. Across the locations, we recorded stand counts at two growth stages (VC and V2) to determine germination rate and impacts due to seedling death. We also recorded plant vigor variables at the V2 growth stage (plant height, biomass, and dry biomass). Throughout the early season, we also had drone flights performed over the trials in an attempt to build a robust method of measuring plant vigor due to seed treatments. These drone flights, however, were not conducted in every trial. At the end of the season, yield was collected from all plots and adjusted to 13% moisture. Preliminary analyses across all locations demonstrate that the seed treatment CruiserMaxx led to higher plant populations, while the addition of the planter box biological products did not improve plant populations. For yield across all environments, there were no differences in yield; however, the treatments with CruiserMaxx consistently had the highest mean yields. There were also differences observed between treatments in specific locations during this season. We are still aligning the drone imagery data, and analysis will be performed after. During the spring of 2026, we will be updating the protocol for this objective for the 2026 field season.
Objective 2c. Biological control of SDS by seed treatments is being led by Dr. Daren Mueller at Iowa State University. A total of 5 seed treatment programs were used to evaluate their effect on SDS. Trials were conducted in fields naturally infested with SDS.
Treatment Number Fungicide Program
1 Non-treated Control
2 Base (CruiserMaxx) @1.38 floz/140,000 seeds
3 Base + CeraMax + Germate Plus
4 Base + Avodigen + Adaplan + Ethos Elite
5 Base + TBZ + Headsup + Biost 2nd Gen + Ascribe SAR
6 Base + ILEVO
In the 2025 growing season, 15 locations were tested for this study. Across the locations, we recorded stand counts to determine plant populations. In the reproductive growth stages, SDS root rot and foliar disease severity index was recorded. At the end of the season, yield was also collected from all plots and adjusted to 13% moisture. Across all environments, plant populations did differ, but no biological seed treatments were different than the non-treated and were all lower than the base seed treatment. We did not observe any differences in root rot severity, and the foliar disease severity index was lowest due to the ILEVO treatment, with no differences being observed due to the biological treatments. No yield differences were observed. During the spring of 2026, we will be updating the protocol for the evaluation of new products for this particular objective for the 2026 field season.
Objective 3. Farmer Survey
Dr. Horacio Lopez-Nicora from the Ohio State University is leading Objective 3. As a part of this objective, we implemented a qualitative survey to better understand how soybean farmers across the North Central region make disease management decisions and which factors most strongly influence those choices. The survey, conducted by Kynetec, included in-depth interviews with 20 soybean growers representing 13 states and a range of farm sizes. Results showed that disease management decisions are rarely driven by a single factor; instead, growers balance weather patterns, perceived disease risk, crop value, field characteristics, and operational logistics when deciding whether and how to manage disease. While white mold, frogeye leaf spot, and other soilborne and foliar diseases remain persistent concerns in parts of the region, many growers described highly variable disease pressure year-to-year, reinforcing the prevalence of “every-year” versus “weather-dependent” disease management strategies.
Survey findings also identified important knowledge gaps and decision barriers that directly inform future research and Extension priorities. Awareness and concern about fungicide resistance varied widely by region, with greater concern in areas where resistance has been documented, while other growers relied heavily on retailers or crop advisors to manage resistance risk. Information sources most trusted by growers included seed dealers, agronomists, peers, and Extension, although growers expressed a desire for more localized, timely, and economically focused data—particularly research that clarifies yield benefits and return on investment for disease management decisions. Collectively, these results help us better understand gaps in the understanding of farmer disease management decisions. These results will help us in the development of a quantitative survey that will be developed in Year 2 of this project.
Objective 4. The development of new Extension material has been progressing nicely. Through the Crop Protection Network, our group has been involved in the updating of publications as of the spring of 2025 including the ‘Fungicide Efficacy for Control of Soybean Foliar Diseases’, ‘Fungicide Efficacy for Control of Soybean Seedling Diseases’, and ‘Soybean Disease Loss Estimates from the United States and Ontario, Canada – 2024’. Further, new publications involving our team included the ‘Scouting for Soybean Stem Diseases’, ‘Monitoring for resistance to the SDHI fungicide seed treatments ILEVO (fluopyram) and Saltro (pydiflumetofen) for soybean sudden death syndrome (SDS) management’. Also, a new CPN TV video was recently released titled ‘White Mold: Insights and Updates for 2025’ which was created by Drs. Chilvers, Smith, and Webster. We also released the Soybean White Mold ROI Calculator which was mentioned in Objective 1C. Progress is moving smoothly with the development of new Extension material for the benefit of North Central soybean farmers, and more content will be developed in the coming years of this project.

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This project delivers powerful decision-making support for farmers looking to refine their disease management practices. By comparing high- and low-intensity strategies, growers will discover which combinations of fungicides, seed treatments, and cultural techniques are most likely to offer a profitable return under their specific environmental conditions. Leveraging multi-year, multi-state trial data means that recommendations can be tailored to diverse climates and production systems, ensuring that farmers receive regionally relevant guidelines rather than one-size-fits-all recommendations.
Additionally, the new and refined decision-support tools, most notably the ROI calculators, put real-time economic data at farmers’ fingertips. Instead of guessing, farmers can input local costs and grain prices to obtain instant estimates of which chemical applications will potentially bring the highest probability of economic gain. This clarity helps farmers avoid unnecessary expenses and better target investments in fungicides or biological products, protecting both yields and profit margins.
Another key benefit is the expansion of reliable, research-based information on biological control products. With the growing demand for sustainable solutions, many producers are curious about these newer technologies yet lack consistent field data to guide adoption. The project’s uniform trials on white mold, seedling diseases, and sudden death syndrome will provide a wealth of practical, unbiased performance data, giving farmers a clear sense of how well biologicals stack up against conventional controls.
The comprehensive survey of farmer practices ensures that the research remains grounded in real-world challenges. By capturing insights into why farmers make certain decisions and what knowledge gaps persist, the project team can craft targeted Extension resources, updated efficacy tables, fact sheets, and webinars that directly address farmer needs. This streamlined communication will enable farmers to apply project findings quickly and effectively.
Finally, the multi-state collaboration allows for an established team of pathologists prepared for rapid responses to evolving threats. As new diseases emerge and greater changes in production systems occur, this established network of plant pathologists and Extension specialists will be able to share data, solutions, and strategies across state lines. In doing so, the project builds a supportive infrastructure that keeps soybean farmers well-prepared, profitable, and competitive in the face of changing agricultural landscapes.