Current Critical Issues Projects

Each year, the North Central IPM Center chooses to fund research projects related to important pest concerns; the pests may threaten crop productivity or human health or safety. Funding may be awarded to Critical Issue Projects that provides opportunity to better understand a pest's biology or that seek ways to better manage the pest (or both). Pest threats may include diseases, weeds or insects. Learn more about the details of our Critical Issues grant opportunities and how to apply.

Past Critical Issues Projects


Survey of Nematode Communities in Soils of the North Central Region

Project Director: Mandy Bish, University of Missouri

Soil health is essential to ensure our food security. An estimated 95% of the global food supply is produced on soils. Nematode communities are commonly used bioindicators to assess the health of soil ecosystems and impact of disturbances caused by environmental and anthropogenic events. Yet information on nematode community dynamics in the North Central region of the US remains limited.  Can we increase knowledge of nematode community dynamics in the North Central US to better understand and measure our impacts on the soil and potential disruptions to the soil food web?  

We propose to utilize morphological characterization and DNA sequencing to develop a baseline understanding of nematode communities in the North Central United States.  The initial focus will be on undisturbed soils in four different ecoregions of Missouri.  Characterization of nematode communities in these soils will serve as baseline information for future projects. We plan to utilize this baseline data generated to secure future funding that will allow us to (1)  monitor shifts in nematode community compositions over time and with changing climate conditions and (2) compare nematode communities from undisturbed and disturbed soils to better understand environmental and anthropogenic effects on North Central US soil health.


  • Collect and preserve nematode samples from undisturbed or minimally disturbed areas within four different ecoregions of Missouri that span into seven additional North Central states
  • Image up to 50 nematodes per sample to develop a nematode reference guide
  • Use morphology to characterize nematodes within each sample
  • Extract nematode DNA from each sample for amplification and genomic sequencing with use of selected nematode-specific markers


Improving our Ability to Detect, Monitor and Manage Corn Tar Spot in the Great Plains

Project Director: Tamra Jackson-Ziems, University of Nebraska-Lincoln

Tar spot disease of corn has caused yield losses of up to 50% in severe cases in some Midwest fields since its first confirmation in the United States in 2015 in Indiana and Illinois. Movement of the fungus causing tar spot, Phyllachora maydis, to the Great Plains states of Kansas, Nebraska, and South Dakota in 2021to 2022 has led to development of tar spot in new areas of the country where corn production practices and environments vary greatly. It is unclear how tar spot will respond in these new areas, especially where overhead pivot irrigation is often common and expected to exacerbate disease severity based on observations in other states. These uncertainties create greater risk for producers in the Great Plains.

In addition, on the forefront of the movement of the tar spot pathogen into the Great Plains, there’s need for additional diagnostic resources. Many field practitioners already struggle with disease diagnoses and especially differentiating similar symptoms of diseases. Diagnostic mistakes and delays can lead to ineffective management decisions and unnecessary expenses for producers. This project proposes outreach activities to demonstrate and train users in the region on the use of new, affordable microscope tools that are now widely available to enhance their diagnostic capabilities of tar spot and other common diseases.

Additionally, fields will be selected across the three participating Great Plains states of Kansas, Nebraska, and South Dakota, which have had confirmed issues with tar spot. The disease severity will be documented frequently through the growing season on plants in adjacent irrigated and non-irrigated areas under varying irrigation regimes. Disease progression will be compared to better understand the impacts of the diverse growing conditions and irrigation on tar spot development. Finally, tar spot samples from the Great Plains states will be compared phylogenetically to assess for fitness differences in those found in the region versus those found in other parts of the country.


  • Offer hands-on, interactive training workshops with affordable, contemporary microscopic tools focused on corn tar spot disease diagnostics
  • Evaluate tar spot development under different irrigated crop production environments in the Great Plains
  • Evaluate genetic and morphological diversity of Phyllachora maydis causing tar spot in the Great Plains.


Weed Emergence Scouting Tool (WEST)

Project Director: Melissa Widhalm, Purdue University

U.S. corn and soybean production systems are heavily reliant on post-emergence applied herbicides. However, overuse of post-emergence herbicides combined with frequent resprays to control weed escapes has resulted in the rapid spread of herbicide-resistant weeds, necessitating increased use of soil residual herbicides with different sites of action and pre-plant tillage to provide additional control measures before the crop is planted. Soil residual herbicides work by getting into the soil solution and coming into contact with a germinating weed seedling right after the germination process has initiated. Freshly germinated weed seeds are also very susceptible to tillage control measures. Understanding and communicating to farmers and spray applicators about when weeds will be germinating and when peak weed emergence will occur allows for more timely applications of soil residual herbicides and the use of tillage to control germinating weed seedlings.

We propose to develop the Weed Emergence Scouting Tool (WEST). This product will be a real-time tool for monitoring first and peak emergence of giant ragweed and waterhemp in the Midwest to support more effective weed management with soil residual herbicides or tillage. Past research has identified the emergence sequence for numerous weed groups based on growing degree day (GDD) accumulations, but weed management historically has not utilized temperature-based scouting protocols. The WEST will integrate weed emergence and management knowledge with high-resolution weather and climate data to develop a first-of-its-kind tool that supports timely soil residual herbicide use and tillage.


  • Gathering field observations of first and peak emergence for giant ragweed and waterhemp and comparing results to known emergence sequences
  • Developing the Weed Emergence Scouting Tool (WEST), which includes GDD-based weed emergence climatology, real-time emergence tracking, and user-submitted emergence observations
  • Disseminating the WEST to key audiences across the region