Gene Map Reveals How Black-Grass Resists Herbicides
The research-stage findings could inform future herbicide design and crop management as resistant weeds spread.
Updated on Nov. 3, 2026 in Botany
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Clemson University researchers, working with international collaborators, identified the genes behind non-target site herbicide resistance in black-grass, a weed that resists many herbicides. The work is research-stage; it describes genetic findings rather than a shipped herbicide or crop tool.
Why it matters
Non-target site resistance, also called metabolic resistance, involves more changes across the plant than target-site resistance, which is typically tied to a specific herbicide or group. Mapping the genes involved gives weed scientists a clearer basis for designing new herbicides and crop management strategies as resistant weeds spread.
The study compared two populations that independently evolved non-target site resistance against one susceptible population, and found a shared core set of genes alongside unique genes in each population. The researchers built a genetic roadmap showing where these genes sit on black-grass chromosomes, though exact gene counts and herbicide-specific details are not given in the source.
The players
Clemson University
A U.S. research university whose team, led by Saski, identified the resistance genes using Palmetto Cluster high-performance computing.
Rothamsted Research
A UK agricultural research institution that developed the two resistant and one susceptible black-grass populations used in the study.
University of Copenhagen
A Danish university that collaborated on the black-grass genetic research.
The details
Non-target site resistance works by changing how the plant metabolizes a herbicide, rather than altering the specific site the chemical targets. To find the responsible genes, Rothamsted Research developed two populations that independently evolved this resistance over several years, and researchers compared them with a susceptible population. Clemson's Palmetto Cluster, a high-performance computing system, processed the resulting data, and the team mapped where the genes lie on black-grass chromosomes.
Timeline
Black-grass completes its lifecycle within the cereal crop growing season, which is why it can evade seasonal control.
Rothamsted researchers spent years developing the genetic study populations used in the work.
The Tech Race
Non-target site resistance is harder to manage than target-site resistance because it spans more of the plant's biology, so mapping its genetic basis is a distinct research direction from target-site work. The Clemson-led genetic roadmap sets a reference point for future herbicide design, though the source does not name competing programs.
The source does not give a timeline for herbicides or crop management tools derived from these genetic findings, so availability for farmers is unannounced. Growers dealing with resistant black-grass should not expect new products from this research in the near term.
The takeaway
The research team believes this genetic knowledge may help usher in new herbicides and improved crop management. Watch for peer-reviewed publication of the genetic roadmap and any follow-up field trials, which would show whether the findings translate beyond the laboratory populations.
Further reading
For background on how weeds evolve resistance, explore our Botany coverage.
Source note: This article includes information reported by Farm Progress.
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