Multiple resistant Kochia scoparia from Czech Republic

International Survey of Herbicide-Resistant Weeds

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Thursday, October 31, 2024

MULTIPLE RESISTANT KOCHIA
(Kochia scoparia)

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)

Czech Republic

INTRODUCTION		KOCHIA
Kochia (Kochia scoparia) is a dicot weed in the Chenopodiaceae family. In Czech Republic this weed first evolved multiple resistance (to 2 herbicide sites of action) in 1996 and infests Railways, and Roadsides. Multiple resistance has evolved to herbicides in the Groups 2 (Legacy B), and PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2). These particular biotypes are known to have resistance to atrazine, chlorsulfuron, imazapyr, metsulfuron-methyl, nicosulfuron, prosulfuron, rimsulfuron, sulfosulfuron, thifensulfuron-methyl, tribenuron-methyl, and triflusulfuron-methyl and they may be cross-resistant to other herbicides in the Groups 2 (Legacy B), and PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2). The 'Group' letters/numbers that you see throughout this web site refer to the classification of herbicides by their site of action. To see a full list of herbicides and HRAC herbicide classifications click here.

QUIK STATS (last updated Dec 12, 2000 )
Common Name	Kochia
Species	Kochia scoparia
Group	Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B) PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
Herbicides	atrazine, chlorsulfuron, imazapyr, metsulfuron-methyl, nicosulfuron, prosulfuron, rimsulfuron, sulfosulfuron, thifensulfuron-methyl, tribenuron-methyl, and triflusulfuron-methyl
Location	Czech Republic
Year	1996
Situation(s)	Railways, and Roadsides
Contributors - (Alphabetically)	Daniela Chodová
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NOTES ABOUT THIS BIOTYPE

AREAS FOUND

Daniela Chodová

Jan Mikulka Kochia scoparia is classified among foreign expansive weeds. The occurrence of imazapyr resistant kochia was identified in 1996 in railroad areas following irregular applications of imazapyr and atrazine. This species is spreading to other localities than those along the railroads (crossroad, roads, unkept areas).

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GENETICS

Daniela Chodová

Jaroslav Salava, Daniela Chodová, Jan Mikulka The resistance to ALS-inhibiting herbicides in all Czech kochia (Kochia scoparia /L./ Schrad.) biotypes studied was conferred by a mutation at codon 574 of the ALS gene. Analysis of the results of DNA sequencing indicated that the mutation induced a leucine for tryptophan substitution.

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GENETICS

Daniela Chodová

Daniela Chodová, Jaroslav Salava The ploidy level and chromosome numbers were verified in nine Czech of kochia from various sites with different susceptibility to acetolactate synthase (ALS)-inhibiting and atrazine herbicides. Radicles 5-15 mm in length from pre-germinated seeds of kochia were used for karyologic analysis. None of eleven examined populations comprised a case where all 50 analyzed roots would have the diploid number of chromosomes (2n=18). Tetraploidy (4n=36) of low frequency was found in a population with multiple resistance to atrazine and ALS inhibitors. Besides diploids a high frequency of mixoploids was recorded

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ACADEMIC ASPECTS

Confirmation Tests

Field, Greenhouse, and Laboratory trials comparing a known susceptible Kochia biotype with this Kochia biotype have been used to confirm resistance. For further information on the tests conducted please contact the local weed scientists that provided this information.

Genetics

Genetic studies on HRAC Group 2, 5 resistant Kochia indicate that the inheritance is determined by a nuclear trait. There may be a note below or an article discussing the genetics of this biotype in the Fact Sheets and Other Literature

Mechanism of Resistance

Studies on the mechanism of resistance of multiple resistant Kochia from Czech Republic indicate that resistance is due to an altered target site. There may be a note below or an article discussing the mechanism of resistance in the Fact Sheets and Other Literature

Relative Fitness

Researchers have indicated that Group 2, 5/B, C1 C2 resistant Kochia is ecologically less fit than normal susceptible Kochia. There may be a note below or an article discussing the fitness of this biotype in the Fact Sheets and Other Literature

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CONTRIBUTING WEED SCIENTISTS

DANIELA CHODOVÁ

Research Associate Research Institute Of Crop Production Plant Protection Po Box 1369 Prague 6, CS-161 06, Ruzyne Czech Republic Email Daniela Chodová

ACKNOWLEDGEMENTS
The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Czech Republic have been instrumental in providing you this information. Particular thanks is given to Daniela Chodová for providing detailed information.

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Herbicide Resistant Kochia Globally
(Kochia scoparia)

Country

FirstYear

Situation

Active Ingredients

Site of Action

Canada (Manitoba)

1988

Industrial sites, Spring Barley, and Wheat

chlorsulfuron, imazethapyr, metsulfuron-methyl, thifensulfuron-methyl, triasulfuron, and tribenuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

Canada (Saskatchewan)

1988

Cropland, and Wheat

thifensulfuron-methyl, and tribenuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

Canada (Alberta)

1989

Spring Barley, and Wheat

chlorsulfuron, metsulfuron-methyl, thifensulfuron-methyl, and tribenuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

Canada (Alberta)

2012

Spring Barley, and Wheat

glyphosate, thifensulfuron-methyl, and tribenuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

Canada (Saskatchewan)

2012

Canola, Spring Barley, and Wheat

glyphosate, thifensulfuron-methyl, and tribenuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

Canada (Manitoba)

2014

Corn (maize), and Soybean

glyphosate, thifensulfuron-methyl, and tribenuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

Canada (Saskatchewan)

2015

Spring wheat

dicamba, fluroxypyr, thifensulfuron-methyl, and tribenuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
Auxin Mimics ( HRAC Group 4 (Legacy O)

Canada (Alberta)

2017

Canola, Corn (maize), Fallow, Lentils, Peas, Wheat, and Winter barley

dicamba, glyphosate, thifensulfuron-methyl, and tribenuron-methyl

Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
Auxin Mimics ( HRAC Group 4 (Legacy O)

Canada (Saskatchewan)

2021

Mustard

saflufenacil

Inhibition of Protoporphyrinogen Oxidase ( HRAC Group 14 (Legacy E)

Czech Republic

1996

Railways, and Roadsides

atrazine, chlorsulfuron, imazapyr, metsulfuron-methyl, nicosulfuron, prosulfuron, rimsulfuron, sulfosulfuron, thifensulfuron-methyl, tribenuron-methyl, and triflusulfuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Kansas)

1976

Corn (maize), and Railways

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Colorado)

1982

Corn (maize)

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Montana)

1984

Railways

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Wyoming)

1984

Corn (maize)

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Iowa)

1985

Railways

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Wisconsin)

1987

Corn (maize), and Railways

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (North Dakota)

1987

Cropland, and Wheat

chlorsulfuron, and metsulfuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Kansas)

1987

Cropland, and Wheat

chlorsulfuron

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (New Mexico)

1988

Railways, and Roadsides

sulfometuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (South Dakota)

1988

Cropland, and Wheat

chlorsulfuron

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Idaho)

1989

Roadsides, and Wheat

chlorsulfuron

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Montana)

1989

Cropland, and Wheat

chlorsulfuron, and metsulfuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Washington)

1989

Cereals, and Wheat

chlorsulfuron

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Colorado)

1989

Roadsides, and Wheat

metsulfuron-methyl, and triasulfuron

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Illinois)

1992

Cropland, and Railways

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Oklahoma)

1992

Roadsides, and Wheat

chlorsulfuron, metsulfuron-methyl, and sulfometuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Oregon)

1993

Wheat

chlorsulfuron, metsulfuron-methyl, and triasulfuron

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Minnesota)

1994

Cropland, and Wheat

imazethapyr, thifensulfuron-methyl, and tribenuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Montana)

1994

Cropland, and Wheat

dicamba, and fluroxypyr

Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (Indiana)

1995

Railways

atrazine, cyanazine, and metsulfuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (North Dakota)

1995

Wheat

dicamba

Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (Illinois)

1995

Corn (maize), Cropland, and Wheat

atrazine, and metsulfuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Wisconsin)

1995

Roadsides

sulfometuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Wyoming)

1996

Wheat

metsulfuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Idaho)

1997

Roadsides

dicamba

Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (Utah)

1998

Industrial sites

sulfometuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (North Dakota)

1998

Corn (maize)

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Texas)

1998

Wheat

metsulfuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Colorado)

1999

Corn (maize)

dicamba

Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (North Dakota)

2004

Railways

diuron, metribuzin, and tebuthiuron

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Michigan)

2005

Sugar beets

imazamox, and triflusulfuron-methyl

Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)

United States (Kansas)

2007

Corn (maize), Cotton, and Soybean

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Nebraska)

2009

Corn (maize)

dicamba

Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (South Dakota)

2009

Corn (maize), and Soybean

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Nebraska)

2011

Corn (maize), and Soybean

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (North Dakota)

2012

Corn (maize), and Soybean

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Montana)

2012

Cereals

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Colorado)

2012

Cereals

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Oklahoma)

2013

Corn (maize)

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Montana)

2013

Wheat

glyphosate, metsulfuron-methyl, thifensulfuron-methyl, and tribenuron-methyl

Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Kansas)

2013

Corn (maize)

atrazine, chlorsulfuron, dicamba, and glyphosate

Multiple Resistance: 4 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (Kansas)

2013

Corn (maize), and Sorghum

dicamba, fluroxypyr, and glyphosate

Multiple Resistance: 2 Sites of Action
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
Auxin Mimics ( HRAC Group 4 (Legacy O)

United States (Nebraska)

2014

Corn (maize)

atrazine

PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)

United States (Oregon)

2014

Corn (maize), and Sugar beets

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Idaho)

2014

Corn (maize), and Sugar beets

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

United States (Wyoming)

2014

Sugar beets

glyphosate

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)

Literature about Similar Cases

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Hall, L. M. ; Beckie, H. J. ; Low, R. ; Shirriff, S. W. ; Blackshaw, R. E. ; Kimmel, N. ; Neeser, C.. 2014. Survey of glyphosate-resistant kochia (Kochia scoparia L. Schrad.) in Alberta. Canadian Journal of Plant Science 94 : 127 - 130.

Glyphosate-resistant (GR) kochia was identified in Warner county in southern Alberta in 2011. To determine the scale of the distribution and frequency of GR kochia, a randomized stratified survey of more than 300 locations (one population per location) in southern Alberta was conducted in the fall of 2012. Mature plants were collected, seed separated, and F₁ seedlings screened by spraying with glyphosate at 900 g a.e. ha^-1 under greenhouse conditions. Screening confirmed 13 GR kochia sites: seven in Warner county, five in Vulcan county, and one in Taber county. The frequency of GR individuals in a population ranged from 0.3 to 98%. GR kochia were found in arid areas where chemical fallow is a significant component of the rotation. Economic and agronomic impact of this GR weed biotype is compounded because of multiple resistance to acetolactate synthase-inhibiting herbicides..

Linda M. Hall, Hugh J. Beckie, Ryan Low, Scott W. Shirriff, Robert E. Blackshaw, Nicole Kimmel, Christoph Neeser. 2014. Survey of glyphosate-resistant kochia (Kochia scoparia L. Schrad.) in Alberta. Can. J. Plant Sci 94 : 127 - 130.

Glyphosate-resistant (GR) kochia was identified in Warner county in southern Alberta in 2011. To determine the scale of the distribution and frequency of GR kochia, a randomized stratified survey of more than 300 locations (one population per location) in southern Alberta was conducted in the fall of 2012. Mature plants were collected, seed separated, and F1 seedlings screened by spraying with glyphosate at 900 g a.e. ha−1 under greenhouse conditions. Screening confirmed 13 GR kochia sites: seven in Warner county, five in Vulcan county, and one in Taber county. The frequency of GR individuals in a population ranged from 0.3 to 98%. GR kochia were found in arid areas where chemical fallow is a significant component of the rotation. Economic and agronomic impact of this GR weed biotype is compounded because of multiple resistance to acetolactate synthase-inhibiting herbicides..

Waite, J. ; Thompson, C. R. ; Peterson, D. E. ; Currie, R. S. ; Olson, B. L. S. ; Stahlman, P. W. ; Al-Khatib, K.. 2013. Differential kochia (Kochia scoparia) populations response to glyphosate. Weed Science 61 : 193 - 200.

Kochia is a troublesome weed throughout the western United States. Although glyphosate effectively controls kochia, poor control was observed in several no-till fields in Kansas. The objectives of this research were to evaluate kochia populations response to glyphosate and examine the mechanism that causes differential response to glyphosate. Glyphosate was applied at 0, 54, 109, 218, 435, 870, 1305, 1740, 3480, and 5220 g ae ha^-1 on 10 kochia populations. In general, kochia populations differed in their response to glyphosate. At 21 d after treatment, injury from glyphosate applied at 870 g ha^-1 range from 4 to 91%. In addition, glyphosate rate required to cause 50% visible injury (GR₅₀) ranged from 470 to 2149 g ha^-1. Differences in glyphosate absorption and translocation and kochia mineral content were not sufficient to explain differential kochia response to glyphosate..

Légère, A. ; Stevenson, F. C. ; Beckie, H. J. ; Warwick, S. I. ; Johnson, E. N. ; Hrynewich, B. ; Lozinski, C.. 2013. Growth characterization of kochia (Kochia scoparia) with substitutions at Pro₁₉₇ or Trp₅₇₄ conferring resistance to acetolactate synthase-inhibiting herbicides. Weed Science 61 : 267 - 276.

Over 90% of Canadian kochia populations are resistant to acetolactate synthase (ALS)-inhibiting herbicides. We questioned whether the target site-based resistance could affect plant growth and competitiveness. Homozygous F₂ herbicide-resistant (HR) kochia plants with an amino acid substitution at Trp₅₇₄ (sources: Alberta [AB], Saskatchewan [SK], and Manitoba [MB]), or Pro₁₉₇ (MB, AB with two populations) were grown in replacement series with homozygous F₂ herbicide-susceptible (HS) plants from the corresponding heterogeneous population (total: six populations). In pure stands, growth of HR plants from AB and SK was similar to that of HS plants, regardless of mutation; conversely, MB2-HR plants (Trp₅₇₄Leu) developed more slowly and were taller than MB2-HS plants. Final dry weight of HR plants in pure stands was similar across all six populations, whereas that for HS plants in pure stands and HR-HS plants in mixed stands (50-50%) varied with population. Results for AB and SK populations suggest little impact of either ALS mutation on kochia growth, whereas those for MB lines would suggest an unidentified factor (or factors) affecting the HS, HR, or both biotypes. The variable response within and between lines, and across HS biotypes highlights the importance of including populations of various origins and multiple susceptible controls in HR biotype studies..

Beckie, H. J. ; Blackshaw, R. E. ; Low, R. ; Hall, L. M. ; Sauder, C. A. ; Martin, S. ; Brandt, R. N. ; Shirriff, S. W.. 2013. Glyphosate- and acetolactate synthase inhibitor-resistant kochia (Kochia scoparia) in western Canada. Weed Science 61 : 310 - 318.

In summer, 2011, we investigated suspected glyphosate-resistant (GR) kochia in three chem-fallow fields (designated F1, F2, F3, each farmed by a different grower) in southern Alberta. This study characterizes glyphosate resistance in those populations, based on data from dose-response experiments. In a greenhouse experiment, the three populations exhibited a resistance factor ranging from 4 to 6 based on shoot biomass response (GR₅₀ ratios), or 5 to 7 based on survival response (LD₅₀ ratios). Similar results were found in a field dose-response experiment at Lethbridge, AB, in spring 2012 using the F2 kochia population. In fall 2011, we surveyed 46 fields within a 20-km radius of the three chem-fallow fields for GR kochia. In the greenhouse, populations were screened with glyphosate at 900 g ae ha^-1. Seven populations were confirmed as GR, the farthest site located about 13 km from the three originally confirmed populations. An additional GR population more than 100 km away was later confirmed. Populations were screened for acetolactate synthase (ALS)-inhibitor (thifensulfuron tribenuron) and dicamba resistance in the greenhouse, with molecular characterization of ALS-inhibitor resistance in the F1, F2, and F3 populations. All GR populations were resistant to the ALS-inhibiting herbicide, but susceptible to dicamba. ALS-inhibitor resistance in kochia was conferred by Pro₁₉₇, Asp₃₇₆, or Trp₅₇₄ amino acid substitutions. Based upon a simple empirical model with a parameter for selection pressure, calculated from weed relative abundance and glyphosate efficacy, and a parameter for seedbank longevity, kochia, wild oat, and green foxtail were the top three weeds, respectively, predicted at risk of selection for glyphosate resistance in the semiarid Grassland region of the Canadian prairies; wild oat, green foxtail, and cleavers species were predicted at greatest risk in the subhumid Parkland region. This study confirms the first occurrence of a GR weed in western Canada. Future research on GR kochia will include monitoring, biology and ecology, fitness, mechanism of resistance, and best management practices..

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