Abstract
Herbicide-resistant kochia is an increasing concern for growers in the northwestern United States. Four suspected glyphosate-resistant (Gly-R) kochia accessions (referred to as GIL01, JOP01, CHES01, and CHES02) collected in fall 2012 from four different chemical-fallow fields in northern Montana were evaluated. The objectives were to confirm and characterize the level of glyphosate resistance in kochia accessions relative to a glyphosate-susceptible (Gly-S) accession and evaluate the effectiveness of various POST herbicides for Gly-R kochia control. Whole-plant dose–response experiments indicated that the four Gly-R kochia accessions had 7.1- to 11-fold levels of resistance relative to the Gly-S accession on the basis of percent control ratings (I 50 values). On the basis of shoot dry weight response (GR 50 values), the four Gly-R kochia accessions exhibited resistance index (R/S) ratios ranging from 4.6 to 8.1. In a separate study, the two tested Gly-R accessions (GIL01 and JOP01) showed differential response (control and shoot dry weight reduction) to various POST herbicides 21 d after application (DAA). Paraquat, paraquat + linuron, carfentrazone + 2,4-D, saflufenacil alone or with 2,4-D, and bromoxynil + fluroxypyr effectively controlled (99 to 100%) and reduced shoot dry weight (88 to 92%) of the GIL01 accession, consistent with the Gly-S kochia accession; however, bromoxynil + MCPA and bromoxynil + pyrasulfotole provided 76% control and 83% shoot dry weight reduction of the GIL01 accession and were lower compared with the Gly-S accession. The JOP01 accession exhibited lower control or shoot dry weight reduction to all herbicides tested, except dicamba, diflufenzopyr + dicamba + 2,4-D, paraquat + linuron, and bromoxynil + pyrasulfotole, compared with the Gly-S or GIL01 population. Furthermore, paraquat + linuron was the only treatment with ≥ 90% control and shoot dry weight reduction of the JOP01 kochia plants. Among all POST herbicides tested, glufosinate was the least effective on kochia. This research confirms the first evolution of Gly-R kochia in Montana. Future research will investigate the mechanism of glyphosate resistance, inheritance, ecological fitness, and alternative strategies for management of Gly-R kochia.
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Claims 10
Claim · model-written summary
Glyphosate-resistant kochia accessions had 7.1- to 11-fold higher levels of resistance than the susceptible accession on percent control.
- Treatment
- glyphosatee0
- Outcome
- levels of resistancee1
- Direction
- higherinferrede1
- Value
- 7.1- to 11-folde1
- Qualifier
- on the basis of percent control ratings (I 50 values)e1
- Comparator
- Gly-S accessione1
- Setting
- northern Montanae0
BassiaOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Four suspected glyphosate-resistant (Gly-R) kochia accessions (referred to as GIL01, JOP01, CHES01, and CHES02) collected in fall 2012 from four different chemical-fallow fields in northern Montana were evaluated”
e1“Whole-plant dose–response experiments indicated that the four Gly-R kochia accessions had 7.1- to 11-fold levels of resistance relative to the Gly-S accession on the basis of percent control ratings (I 50 values)”
Claim · model-written summary
Glyphosate-resistant kochia accessions had resistance index (R/S) ratios of 4.6 to 8.1 on shoot dry weight response.
- Treatment
- glyphosatee0
- Outcome
- resistance index (R/S) ratiose2
- Direction
- higherinferrede2
- Value
- 4.6 to 8.1e2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Four suspected glyphosate-resistant (Gly-R) kochia accessions (referred to as GIL01, JOP01, CHES01, and CHES02) collected in fall 2012 from four different chemical-fallow fields in northern Montana were evaluated”
e2“On the basis of shoot dry weight response (GR 50 values), the four Gly-R kochia accessions exhibited resistance index (R/S) ratios ranging from 4.6 to 8.1”
Claim · model-written summary
Paraquat and other listed POST herbicides effectively controlled the GIL01 kochia accession (99 to 100%), consistent with the susceptible accession.
- Material
- GIL01 accessione4
- Treatment
- various POST herbicidese3
- Outcome
- controle4
- Direction
- effectively controllede4
- Value
- 99 to 100%e4
- Comparator
- Gly-S kochia accessione4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“In a separate study, the two tested Gly-R accessions (GIL01 and JOP01) showed differential response (control and shoot dry weight reduction) to various POST herbicides 21 d after application (DAA)”
e4“Paraquat, paraquat + linuron, carfentrazone + 2,4-D, saflufenacil alone or with 2,4-D, and bromoxynil + fluroxypyr effectively controlled (99 to 100%) and reduced shoot dry weight (88 to 92%) of the GIL01 accession, consistent with the Gly-S kochia accession”
Claim · model-written summary
Paraquat and other listed POST herbicides reduced shoot dry weight of the GIL01 kochia accession by 88 to 92%, consistent with the susceptible accession.
- Material
- GIL01 accessione4
- Treatment
- various POST herbicidese3
- Outcome
- shoot dry weighte4
- Direction
- reducede4
- Value
- 88 to 92%e4
- Comparator
- Gly-S kochia accessione4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e3“In a separate study, the two tested Gly-R accessions (GIL01 and JOP01) showed differential response (control and shoot dry weight reduction) to various POST herbicides 21 d after application (DAA)”
e4“Paraquat, paraquat + linuron, carfentrazone + 2,4-D, saflufenacil alone or with 2,4-D, and bromoxynil + fluroxypyr effectively controlled (99 to 100%) and reduced shoot dry weight (88 to 92%) of the GIL01 accession, consistent with the Gly-S kochia accession”
Claim · model-written summary
Bromoxynil + MCPA and bromoxynil + pyrasulfotole gave lower control (76%) of the GIL01 accession than the susceptible accession.
- Material
- GIL01 accessione5
- Treatment
- bromoxynil + MCPA and bromoxynil + pyrasulfotolee5
- Outcome
- controle5
- Direction
- lowere5
- Value
- 76%e5
- Comparator
- Gly-S accessione5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Four suspected glyphosate-resistant (Gly-R) kochia accessions (referred to as GIL01, JOP01, CHES01, and CHES02) collected in fall 2012 from four different chemical-fallow fields in northern Montana were evaluated”
e5“bromoxynil + MCPA and bromoxynil + pyrasulfotole provided 76% control and 83% shoot dry weight reduction of the GIL01 accession and were lower compared with the Gly-S accession”
Claim · model-written summary
Bromoxynil + MCPA and bromoxynil + pyrasulfotole gave lower shoot dry weight reduction (83%) of the GIL01 accession than the susceptible accession.
- Material
- GIL01 accessione5
- Treatment
- bromoxynil + MCPA and bromoxynil + pyrasulfotolee5
- Outcome
- shoot dry weight reductione5
- Direction
- lowere5
- Value
- 83%e5
- Comparator
- Gly-S accessione5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Four suspected glyphosate-resistant (Gly-R) kochia accessions (referred to as GIL01, JOP01, CHES01, and CHES02) collected in fall 2012 from four different chemical-fallow fields in northern Montana were evaluated”
e5“bromoxynil + MCPA and bromoxynil + pyrasulfotole provided 76% control and 83% shoot dry weight reduction of the GIL01 accession and were lower compared with the Gly-S accession”
Claim · model-written summary
The JOP01 kochia accession showed lower control or shoot dry weight reduction than the susceptible or GIL01 population to all herbicides tested, with four exceptions.
- Material
- JOP01 accessione6
- Treatment
- all herbicides testede6
- Outcome
- control or shoot dry weight reductione6
- Direction
- lowere6
- Qualifier
- except dicamba, diflufenzopyr + dicamba + 2,4-D, paraquat + linuron, and bromoxynil + pyrasulfotolee6
- Comparator
- Gly-S or GIL01 populatione6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Four suspected glyphosate-resistant (Gly-R) kochia accessions (referred to as GIL01, JOP01, CHES01, and CHES02) collected in fall 2012 from four different chemical-fallow fields in northern Montana were evaluated”
e6“The JOP01 accession exhibited lower control or shoot dry weight reduction to all herbicides tested, except dicamba, diflufenzopyr + dicamba + 2,4-D, paraquat + linuron, and bromoxynil + pyrasulfotole, compared with the Gly-S or GIL01 population. Furthermore, paraquat + linuron was the only treatment with ≥ 90% control and shoot dry weight reduction of the JOP01 kochia plants”
Claim · model-written summary
Paraquat + linuron was the only treatment giving at least 90% control and shoot dry weight reduction of the JOP01 kochia accession.
- Material
- JOP01 kochia plantse6
- Treatment
- paraquat + linurone6
- Outcome
- control and shoot dry weight reductione6
- Direction
- higherinferrede6
- Value
- ≥ 90%e6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e6“The JOP01 accession exhibited lower control or shoot dry weight reduction to all herbicides tested, except dicamba, diflufenzopyr + dicamba + 2,4-D, paraquat + linuron, and bromoxynil + pyrasulfotole, compared with the Gly-S or GIL01 population. Furthermore, paraquat + linuron was the only treatment with ≥ 90% control and shoot dry weight reduction of the JOP01 kochia plants”
Claim · model-written summary
Glufosinate was the least effective POST herbicide on kochia.
- Treatment
- glufosinatee7
- Outcome
- effective on kochiae7
- Direction
- lowerinferrede7
- Comparator
- all POST herbicides testede7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e7“Among all POST herbicides tested, glufosinate was the least effective on kochia. This research confirms the first evolution of Gly-R kochia in Montana”
Claim · model-written summary
Glyphosate-resistant kochia has evolved for the first time in Montana.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e7“Among all POST herbicides tested, glufosinate was the least effective on kochia. This research confirms the first evolution of Gly-R kochia in Montana”
The same questions in other papers
glyphosate · disease · BassiaPositive and negative results
1 in the opposite direction
- positive
paraquat · control · BassiaResults agree
1 paper in the same direction as this paper
- positive
herbicide · control · BassiaPositive and negative results
1 paper in the same direction as this paper · 5 in the opposite direction
- no effect
- positive
- positive
3 papers more in this group
See all 7 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.