Eric Patterson, an assistant professor and weed geneticist in the MSU Department of Plant, Soil and Microbial Sciences (PSM), leads the project that will cover most of the soybean-growing region of the U.S.

EAST LANSING, Mich. — A national research team led by Michigan State University has received a $500,000 grant from the United Soybean Board to develop new diagnostic tools for herbicide-resistant weeds in soybeans. The award currently covers one year but can be extended for up to three years.

Eric Patterson, an assistant professor and weed geneticist in the MSU Department of Plant, Soil and Microbial Sciences (PSM), leads the project that will cover most of the soybean-growing region of the U.S.

Additional MSU team members include Erin Hill, a weed diagnostician with MSU Plant & Pest Diagnostics; Erin Burns, an assistant professor in PSM; and Christy Sprague, a professor in PSM.
The multistate project also brings together partners from Kansas State University, Mississippi State University, Penn State University, Purdue University, Texas A&M AgriLife Research, the University of Arkansas, the University of Illinois, the University of Missouri, and the University of Wisconsin.

For decades, the primary method of weed eradication has been chemical control with herbicides, but growers and researchers are seeing increased levels of resistance in several weed species. Patterson said the primary culprit is an overreliance on a limited number of herbicides.
According to a 2014 study supported by the United Soybean Board, herbicide-resistant weeds cost U.S. soybean growers more than $2 billion annually. Since then, populations of these weeds have proliferated across the country with almost every major crop, boosting that figure substantially when considering all of agriculture.

The new project is called HERMON (Herbicide Resistance Monitoring Network) and is broadly aimed at developing rapid diagnostic tools for resistance detection, increasing screening capacity and improving chemical management recommendations. The work is rooted in extension with an overarching goal to deliver effective strategies directly to soybean growers.

Patterson, whose research program is supported in part by MSU AgBioResearch, said the team anticipates the new project will generate significant economic returns for soybean farmers.
"HERMON will coordinate the efforts of a network of herbicide resistance experts at universities representing the eastern, southern and northcentral soybean-growing regions to develop new technologies that rapidly detect resistance and track its spread," Patterson said. "Ultimately, we're working 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."

HERMON is composed of five complementary objectives that will take place at partner universities.

Researchers from MSU, Arkansas, Mississippi State and Missouri will develop standardized greenhouse diagnostic protocols for resistance detection. Farmers across the U.S. rely on land-grant universities for resistance diagnostic services and recommendations, but MSU is currently the only university in the country that offers a comprehensive greenhouse-based herbicide resistance screening service through the Plant & Pest Diagnostics program.

The piecemeal approach has led to each university using a unique methodology with varying criteria that may not consider new resistance mechanisms. To solve this issue, the team is proposing to position MSU as a northern diagnostic hub for species such as waterhemp, ragweeds and marestail, Mississippi State as a southern hub for grasses, and Arkansas for Palmer amaranth, possibly the most damaging weed for U.S. soybeans. These hubs will coordinate regularly, sharing reference seed and novel cases of resistance for more intense study.
"Standardizing our diagnostic protocols is essential to delivering the most consistent and reliable information to farmers," Patterson said. "These hubs would allow us to cover the entirety of the soybean-growing regions across the country."

Scientists from Penn State and Purdue will lead the creation of rapid testing for known resistance mechanisms, while collaborators from MSU, Penn State, Illinois and Texas A&M AgriLife Research will work to uncover new resistance mechanisms to also develop rapid diagnostics.

Partners at Arkansas, Mississippi State, Purdue and Wisconsin will investigate resistance to soil-applied residual and foliar herbicides in Amaranthus sp., the most common weeds in soybeans. Soil-applied residual herbicides are deployed prior to weed emergence, while foliar products target weeds once they are present in the field.

Prior research has focused primarily on foliar herbicides for resistance diagnostics, but more information is needed on soil-applied residual products because they are often recommended for management. Researchers also want to understand the relationship between both types of herbicide resistance in weed populations.

Finally, Kansas State is leading efforts to disseminate research findings and educate growers about resistance management. This will be done through a variety of platforms, including a Weed Science Society of America panel discussion, direct farmer meetings, questionnaires, and a short video online seminar series that teaches the basics about resistance, diagnostics, management and general weed science.

A portion of the funding will support training opportunities for six graduate students and two postdoctoral researchers across the entire network. These scientists will go on to become experts in resistance management within industry, academia and government positions.

"Training the next generation of weed scientists is a foundational element of the project," Patterson said. "Equipping them with the skills to meet the needs of U.S. growers now and into the future will be vital to the success of our agriculture industries."

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Michigan State University AgBioResearch scientists discover dynamic solutions for food systems and the environment. More than 300 MSU faculty conduct leading-edge research on a variety of topics, from health and agriculture to natural resources. Originally formed in 1888 as the Michigan Agricultural Experiment Station, MSU AgBioResearch oversees numerous on-campus research facilities, as well as 15 outlying centers throughout Michigan. To learn more, visit agbioresearch.msu.edu.