2025
An integrated approach towards the detection, diagnosis, and response to emerging herbicide-resistant weeds in soybean.
Category:
Sustainable Production
Keywords:
(none assigned)
Parent Project:
This is the first year of this project.
Lead Principal Investigator:
Eric Patterson, Michigan State University
Co-Principal Investigators:
Sarah Lancaster, Kansas State University
Christy Sprague, Michigan State University
Luis Avila, Mississippi State University
Caio Brunharo , Pennsylvania State University
Thomas Butts, Purdue University
Bryan Young, Purdue University
Mithila Jugulam, Texas A&M AgriLife Research Center
Patrick Tranel, University of Illinois at Urbana-Champaign
Rodrigo Werle, University of Wisconsin - Madison
+8 More
Project Code:
60065
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:
Effective weed management is critical for maximizing soybean yields and profits. Over the past 30 years, the predominant method for efficient weed control in soybean has been herbicides. Overreliance on a limited number of herbicide sites-of-action (SOAs) has led to a proliferation of herbicide-resistant weed populations across the entire soybean growing region of the United States and beyond. This proposal aims to coordinate the efforts of a network of herbicide resistance experts at universities representing the eastern, southern, and northcentral regions to develop new technologies that rapidly detect resistance and track its spread. These diagnostics tools will be directly translated into faster resistance detection for growers as well as more reliable and accurate recommendations for soybean growers throughout the soybean growing region. Information about this project will be communicated through a strong translational and outreach strategy, developed by extension experts.
Unique Keywords:
#weed management
Information And Results
Project Summary

Effective weed management is crucial for optimizing soybean yields and profitability; however, herbicide resistance poses a significant threat to efficient chemical weed control in soybeans. This proposed project directly addresses this issue through the development of new diagnostic tools, increased resistance screening capacity, and improved recommendations for resistance management. It represents a collaborative effort among some of the world's premier experts in herbicide resistance detection and management, spanning the eastern, southern, and northcentral U.S. soybean growing regions. Key objectives include developing rapid diagnostic tools for herbicide resistance detection, establishing diagnostic standards, discovering new herbicide resistance mechanisms for further diagnostic development, and translating these products directly to farmers. Funding will also provide training opportunities for six graduate students and two post-doctoral researchers, ensuring the development of the next generation of weed scientists. A major outcome will be the creation of a variety of diagnostic tools, which will be made available post-project through local universities across the soybean growing region. Ultimately, this collaborative approach aims to enhance communication and knowledge exchange among scientists, farmers, and agronomists, thereby strengthening the resilience of soybean production against herbicide resistance. If funds are awarded, they will be leveraged to obtain complementary support from private industry and the federal government to extend the proposed work. This project anticipates significant economic returns for soybean farmers, estimated at $87.5 million annually, by providing timely and effective weed resistance management solutions.

Project Objectives

The proposed collaborative effort, spanning multiple soybean growing regions, seeks to address soybean growers’ needs by: i) Establishing a pipeline for identifying resistant weeds and setting diagnostic standards for confirming resistance, ii) Developing and deploying more rapid herbicide resistance diagnostics, iii) Discovering new herbicide resistance mechanisms for future diagnostic development, iv) Understanding how resistance manifests across pre- and post-emergence application timings, and v) Effectively disseminating information to soybean farmers and their advisors. Ultimately, this project aims to establish a broad and collaborative weed science workgroup to facilitate knowledge exchange and the development of decision support tools for local and regional weed management.

Objective 1) Develop standard greenhouse diagnostic protocols for resistance detection.
Objective 2) Create fast assays for known herbicide resistance mechanism detection.
Objective 3) Uncover novel resistance mechanisms for timely development of quick diagnostics.
Objective 4) Investigate resistance to pre- and post-applied herbicides in Amaranthus spp.
Objective 5) Disseminate findings, communicate with growers, and develop human capital.

Project Deliverables

Success will be evaluated by several metrics. First, PIs with extension appointments will incorporate results in their annual extension talks including explanations to growers that suspected resistant samples from soybean farms can be submitted for screening to either MSU or Miss State. The number of those talks, where they were located, and the number of attendants will be recorded. We will also include brief surveys at these meetings to check farmer understanding and willingness to use diagnostic services. Second, we will calculate how many samples are being submitted by soybean growers before, during, and after this project. As word spreads from extension talks about this project, we anticipate more growers being interested in testing. Furthermore, success in developing an herbicide resistance testing network for soybean growers will be measured by assessments conducted during the webinars and farmer panels at the North Central Weed Science Society (NCWSS), Northeastern Weed Science Society (NEWSS), and Southern Weed Science Society (SWSS) annual meetings. Third, we will work with our state soybean commodity groups to publish extension articles about this project and inform growers about herbicide resistance testing. We will measure growers understanding and awareness of testing in the first and last year of the project. Fourth, we will also keep track of the number of 1) protocols developed, 2) papers written, 3) extension articles written, and 4) students graduated that result from this effort. Finally, extension PIs will evaluate changes in growers’ response to putative resistance cases and the adoption of recommendations that are a result of discoveries from this project. All metrics will be collected and reported at the end of the third year of this project.

Progress Of Work

Updated August 1, 2025:
Our project, entitled “An integrated approach towards the detection, diagnosis, and response to emerging herbicide-resistant weeds in soybean” is off to a great start. We met as a group at Weed Science Society of America on February 25th, 2025 to begin planning our first steps and we chose the name “Hermon” (Herbicide resistance monitoring network) to talk about our project in brief.. Funds were received in March and subaward contracts and MTAs initiated immediately. Once funds were dispersed, the 11 PIs on the team were able to open positions at their respective universities and begin the hiring process to find personal to work on this project. Due to all of us working on the school year/student hiring cycle this meant most of us were hiring to start in the summer of fall of 2025. To date we have:
1. A research associate starting at Mississippi in September.
2. A research associate and student already working at Wisconsin
3. A master’s student at Texas
4. A post-doc and master’s student at Arkansas
5. A PhD student starting at Kansas state in September
6. A post-doc already started at Michigan
7. A post-doc already started at Pennsylvania

Those of us with extension appointments have been giving talks to soybean growers throughout the year, especially I the summer months about the importance of herbicide resistance testing and monitoring, and the importance of germplasm for Hermon. We expect several new populations to be received in late summer and early fall when weeds are putting out seeds. PIs Butts, Werle, Lancaster, and Sprague have especially been active in talks, hosting field days for soybean growers with herbicide demonstrations and appearing on local radio and on agriculture podcasts. Also in extension, PI Lancaster has started collecting interviews with the various PIs on this project as well as other knowledgeable weed scientists to be turned into short-form video essays about various important components of this project including a project overview, the importance of monitoring, the importance of getting your weeds tested, the importance of weed control and herbicide resistance management in general etc. We have developed a plan with USB, TakeAction, and GROW to publish these materials and amplify their impact.

In research we have made progress on several fronts. First we have begun collecting all the information about existing weed seed collections hosted at the various participating universities. This required a standardized database with inclusive fields to capture as much information about available germplasm as possible. With this we will begin sharing important seeds for bulk up and molecular investigation in the next steps of the project. We will also use this information to populate county-level maps with cases of confirmed and suspected herbicide resistance that will be made publicly available to growers. For this, we have begun meeting with the creators of EDDmaps, a powerful agriculture database that can generate up-to-date maps with ease. We are still working on what uploading our data will look like. We have supported their application for a symposium at the 2026 WSSA meeting which has been accepted and both PI Patterson and Lancaster will talk about the Hermon project and herbicide resistance monitoring.

PI Patterson and Tranel have also begun conversations with Corteva about the importance of the Enlist trait and monitoring and studying 2,4 D resistance in both Palmer and Waterhemp. While we have enough budget to tackle some of this resistance case, we have been talking to Corteva to leverage these funds and amplify our capacity to fully understand what drives 2,4D resistance in these species.

PIs Werle and Norsworthy have been working on extensive dose response greenhouse experiments looking at waterhemp resistance to PRE herbicides in Wisconsin and HPPD POST herbicides in Arkansas. The former being importance to protect PPO herbicides for Soybean and the later due to Bayer wanting to include HPPD herbicides in the upcoming HT4 soybeans. PIS Patterson, Werle, and Brunharo have also developing methodology to test for herbicide resistance in agar for Pre herbicides which will greatly accelerate and standardize pre-emergent resistance testing, PI Avila has been screening hundreds of grass weed samples (Goosegrass, Johnsongrass, and Lolium), developing standardized screening and populations for these important soybean weeds.

The remainder of the year will focus on germplasm sharing and bulk up, developing expanded collaborations both within and outside of Hermon, finalizing some of our extension materials, developing new assays for novel herbicide resistance cases, screening new cases of HR as they are discovered later this season, and a focus on methodology standardization.

Final Project Results

Benefit To Soybean Farmers

There exists an urgent need for research that enables growers to swiftly diagnose herbicide resistance in their fields and access up-to-date information and recommendations for effectively managing emerging problems to maintain profitability and environmental sustainability in soybean production.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.