Developing robust identification assays for Amaranthus palmeri in seed mixtures
Don Wyse, Agronomy & Plant Sciences
This project created a highly reliable test for detecting Palmer Amaranth, in individual plants and pools of seed. The test is commercially viable and will be an important tool for Minnesota farmers, crop consultants, and agronomic specialists.
Researchers collected Pigweed samples across the United States as well as Mexico, South America and Africa. Researchers extracted DNA samples from 24 populations of Palmer amaranth and 42 non-Palmer pigweeds, resulting in DNA from over 2,000 individual plants. They sequenced more than 800 of these samples through the University of Minnesota Genomic Center to search for genetic differences between Palmer and the other species. These differences served as a target for developing a set of genetic markers that can be used for species identification. Once developed, the genetic markers were tested against 1,250 pigweed samples to assess their performance.
Palmer amaranth (Amaranthus palmeri) is a weedy annual originally native to the southwestern US and northern Mexico. It can grow several inches in a day, and a single plant can produce as many as one million seeds. In Minnesota, Palmer amaranth is regulated as a prohibited noxious weed. It was only recently introduced to the state via contaminated seed mixes used for conservation plantings. It can reduce corn and soybean yields by 80-90%.
The results of this project will help regulators better identify Palmer-contaminated seed mixtures to protect agricultural lands. Researchers developed a more efficient means of physically separating Amaranthus seeds from other types to drastically increase the volume of seed analysts can test overall. They will also produced a reliable, afforable DNA test for Palmer amaranth identification.
With the help of state partners like the Minnesota Department of Agriculture, the resulting test protocol will provide a strong basis for a proactive seed certification program.
- How can analysts efficiently separate amaranth seeds from other seed types in a mix for a pure sample prior to molecular analysis?
- Can existing DNA markers of Palmer amaranth be validated for implementation in a reliably accurate genetic test?
- What additional DNA markers can be used to increase the accuracy of a positive identification of Palmer amaranth?
Colorado State University, Kansas State University, Minnesota Department of Agriculture, Minnesota Crop Improvement Association
Don Wyse, principal investigator
Anthony Brusa, post-doctoral associate
Jeff Gunsolus, co-investigator
Peter Morrell, co-investigator
Related news & publications
- U of M researchers develop 99.9% accurate genetic test for early detection of Palmer Amaranth (University of Minnesota Research Brief, 2021)
- Protecting Minnesota's corn and soybeans (KSTP-TV)
- Researchers Develop Genetic Test 99.9 Percent Effective In Detecting Palmer Amaranth (WNAX Radio)
- Researchers develop genetic test to detect pigweed (High Plains Journal)
- A needle in a seedstack: An improved method for detection of rare alleles in bulk seed testing through KASP (Pest Management Science, 2021)
- Sorting Seed: How a New DNA Test will Improve Palmer Amaranth Detection
- Meet the Researcher: Anthony Brusa
- Palmer Amaranth Summit in Review
- Video: New genetic test for Palmer amaranth