Researchers Map Genes Behind Black-Grass Herbicide Resistance
Clemson-led team identifies genetic roadmap for non-target site resistance in the weed, which is resistant to many herbicides.
Updated on Nov. 3, 2026 in Botany
Live Poll
Do you think weed resistance to herbicides is a serious threat to the food supply?
Researchers at Clemson University, working with international collaborators, determined the genes behind non-target site herbicide resistance in black-grass. The team found a shared core set of genes plus unique genes across the populations studied.
Why it matters
Non-target site resistance, also called metabolic resistance, involves more changes in the plant than target-site resistance, making it harder to manage with conventional herbicides. The researchers believe the findings may help usher in new herbicides and improved crop management.
The study compared two black-grass populations that independently evolved non-target site resistance against one susceptible population, with each plant capable of producing thousands of seeds. The source does not detail how the genetic roadmap will be applied in practice.
The players
Clemson University
A public research university in South Carolina whose researchers led the genetic study identifying the genes behind black-grass herbicide resistance.
Rothamsted Research
A United Kingdom agricultural research institution that developed the two resistant black-grass populations and one susceptible population used in the study.
University of Copenhagen
A Danish public research university that collaborated with Clemson researchers on the black-grass genetics study.
The details
Researchers at Rothamsted Research developed the two resistant populations over several years, and the Clemson-led team then compared them to identify genes involved in the trait. Using Clemson's Palmetto Cluster high-performance computing resource, the team created a genetic roadmap showing where the genes are located on black-grass chromosomes. Black-grass, native to Europe and Asia and introduced to North America, completes its lifecycle within the cereal crop growing season.
Timeline
Years were spent developing the genetic study populations at Rothamsted Research.
Black-grass completes its lifecycle within the cereal crop growing season.
Big Picture
The work builds on Rothamsted Research's black-grass populations, which evolved non-target site resistance independently, allowing comparison of the genetic mechanisms across lineages. Identifying a shared core set of resistance genes alongside population-specific ones extends that earlier work from documenting resistance to mapping its genetic architecture.
Growers managing cereal crops face weeds that survive many herbicides, so a genetic map of resistance could eventually inform which products and rotation strategies remain effective. The source does not indicate when new herbicides or management tools based on these findings might reach farmers.
The takeaway
Resistance in weeds like black-grass is driven by a complex set of genes rather than a single change, so managing it will likely require strategies that account for that complexity. Growers should monitor fields for surviving weeds and vary herbicide approaches to slow resistance.
Further reading
For more on how weeds adapt to chemical control, explore our Botany coverage.
Source note: This article includes information reported by Farm Progress.
Live Poll
Do you think weed resistance to herbicides is a serious threat to the food supply?
