Control of Italian Ryegrass (Lolium multiflorum) in Winter Wheat

Field studies were established in 1999 and 2000 to evaluate Italian ryegrass, wheat, and double-crop soybean response to fall and spring postemergence applications of flucarbazone, sulfosulfuron, clodinafop, diclofop, and tralkoxydim applied alone and in combination with thifensulfuron + tribenuron to winter wheat. Fall-applied herbicides caused 5% or less wheat injury. Spring-applied herbicides caused 3 to 45% wheat injury, and the greatest injury occurred with the combination of flucarbazone with thifensulfuron + tribenuron in the spring of 2001. Spring-applied sulfosulfuron, tralkoxydim, diclofop, and clodinafop caused 3 to 6% and 16 to 26% wheat injury in 2000 and 2001, respectively. Herbicide injury to wheat did not reduce wheat grain yield compared with the hand-weeded treatment. Italian ryegrass competition in the nontreated plots reduced wheat yield by as much as 33% compared with herbicide-treated plots. Italian ryegrass control was 89 to 99% from clodinafop and diclofop and 78 to 97% from flucarbazone, with no differences because of application timing in either year of the study. Italian ryegrass control from sulfosulfuron and tralkoxydim was greater from the spring of 2000 applications (94 to 99%) compared with the fall of 1999 applications (65 to 88%). However, in 2001, application timing (fall vs. spring) for sulfosulfuron and tralkoxydim did not affect Italian ryegrass control. Thifensulfuron + tribenuron combined with tralkoxydim reduced control of Italian ryegrass control compared with tralkoxydim alone in both years of the study. Italian ryegrass control was not reduced when thifensulfuron + tribenuron was combined with sulfosulfuron, flucarbazone, diclofop, or clodinafop. Italian ryegrass was controlled effectively by the acetyl-CoA carboxylase–inhibiting herbicides diclofop, clodinafop, and tralkoxydim. However, control of Italian ryegrass with the acetolactate synthase–inhibiting herbicides flucarbazone and sulfosulfuron was inconsistent. Double-crop soybean after wheat did not have foliar symptoms or yield loss from fall- or spring-applied herbicides.

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Mesosulfuron-Resistant Italian Ryegrass (Lolium Multiflorum) Biotype from Texas

Weed Technology ◽

10.1614/wt-08-032.1 ◽

2008 ◽

Vol 22 (3) ◽

pp. 431-434 ◽

Cited By ~ 9

Author(s):

Andrew T. Ellis ◽

Gaylon D. Morgan ◽

Thomas C. Mueller

Keyword(s):

Winter Wheat ◽

Plant Biomass ◽

Lolium Multiflorum ◽

Acetolactate Synthase ◽

Italian Ryegrass ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa ◽

Resistance Level ◽

Greenhouse Experiments

Acetolactate synthase (ALS)–inhibiting herbicides are often used to control Italian ryegrass in winter wheat in Texas. An Italian ryegrass biotype near Waco, TX was evaluated for resistance to mesosulfuron in field and greenhouse experiments. Control of the biotype in the field was less than 10% with the label rate of mesosulfuron (15 g ai/ha). Greenhouse studies confirmed that the biotype was resistant to mesosulfuron; control of the biotype was less than 35% at 120 g ai/ha mesosulfuron. The herbicide dose required to reduce plant biomass of a susceptible and the Waco biotype by 50% (GR50) was 1.3 and 31 g ai/ha, respectively, indicating a resistance level of 24-fold in the Waco biotype. However, the Waco biotype was controlled with the acetyl-CoA carboxylase inhibitors diclofop and pinoxaden.

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Comparison of Herbicides for Control of Diclofop-Resistant Italian Ryegrass in Wheat

Agriculture ◽

10.3390/agriculture8090135 ◽

2018 ◽

Vol 8 (9) ◽

pp. 135 ◽

Cited By ~ 1

Author(s):

Taghi Bararpour ◽

Ralph Hale ◽

Gurpreet Kaur ◽

Jason Bond ◽

Nilda Burgos ◽

...

Keyword(s):

Triticum Aestivum ◽

Winter Wheat ◽

Lolium Perenne ◽

Wheat Yield ◽

Field Studies ◽

Triticum Aestivum L ◽

Italian Ryegrass ◽

Lolium Perenne L

Diclofop-resistant Italian ryegrass (Lolium perenne L. ssp. Multiflorum (Lam.) Husnot) is a dominant weed problem in non-irrigated winter wheat (Triticum aestivum L.) in mid-south USA. Field studies were conducted from 2001 to 2007 to evaluate the efficacy of herbicides for diclofop-resistant ryegrass control and effect on wheat yield. In 2001 through 2004, chlorsulfuron/metsulfuron at 0.026 kg ha−1 preemergence (PRE) followed by (fb) mesosulfuron at 0.048 kg ha−1 at 4-leaf to 2-tiller ryegrass provided 89% control of diclofop-resistant Italian ryegrass, resulting in the highest wheat yield (3201 kg ha−1). Flufenacet/metribuzin at 0.476 kg ha−1 applied at 1- to 2-leaf wheat had equivalent Italian ryegrass control (87%), but lesser yield (3013 kg ha−1). In 2005–2006, best treatments for Italian ryegrass control were chlorsulfuron/metsulfuron, 0.013 kg ha−1 PRE fb mesosulfuron 0.015 kg ha−1 at 3- to 4-leaf ryegrass (92%); metribuzin, 0.280 kg ha−1 at 2- to 3- leaf wheat fb metribuzin at 2- to 3-tiller ryegrass (94%); chlorsulfuron/metsulfuron (0.026 kg ha−1) (89%); and flufenacet/metribuzin at 1- to 2-leaf wheat (89%). Chlorsulfuron/metsulfuron fb mesosulfuron provided higher yield (3515 kg ha−1) than all other treatments, except metribuzin fb metribuzin.

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Italian Ryegrass (Lolium Multiflorum) Management Options in Winter Wheat in Oklahoma

Weed Technology ◽

10.1614/wt-06-038.1 ◽

2007 ◽

Vol 21 (1) ◽

pp. 151-158 ◽

Cited By ~ 8

Author(s):

Chad S. Trusler ◽

Thomas F. Peeper ◽

Amanda E. Stone

Keyword(s):

Winter Wheat ◽

Plant Density ◽

Control Strategies ◽

Lolium Multiflorum ◽

Wheat Yield ◽

Italian Ryegrass ◽

Wheat Crop ◽

Management Options ◽

Spike Density ◽

Herbicide Treatments

An experiment was conducted at three sites in central Oklahoma to compare the efficacy of Italian ryegrass management options in no-till (NT) and conventional tillage (CT) winter wheat. The Italian ryegrass management options included selected herbicide treatments, wheat-for-hay, and a rotation consisting of double-crop soybean seeded immediately after wheat harvest, followed by early season soybean, and then by wheat. In continuous wheat, before application of glyphosate or tillage, Italian ryegrass plant densities in mid-September were 12,300 to 15,000 plants/m2in NT plots vs. 0 to 500 plants/m2in CT plots. When applied POST, diclofop controlled more Italian ryegrass than tralkoxydim or sulfosulfuron. In continuous wheat, yields were greater in CT plots than in NT plots at two of three sites. None of the Italian ryegrass management options consistently reduced Italian ryegrass density in the following wheat crop. Of the Italian ryegrass control strategies applied to continuous wheat, three herbicide treatments in NT at Chickasha and all treatments in NT at Perry reduced Italian ryegrass density in the following wheat crop. Italian ryegrass plant density in November and spike density were highly related to wheat yield at two and three sites, respectively. No management options were more profitable than rotation to soybean.

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First Detection and Characterization of Cross- and Multiple Resistance to Acetyl-CoA Carboxylase (ACCase)- and Acetolactate Synthase (ALS)-Inhibiting Herbicides in Black-Grass (Alopecurus myosuroides) and Italian Ryegrass (Lolium multiflorum) Populations from Ireland

Agriculture ◽

10.3390/agriculture11121272 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1272

Author(s):

Vijaya Bhaskar Alwarnaidu Vijayarajan ◽

Patrick D Forristal ◽

Sarah K Cook ◽

David Schilder ◽

Jimmy Staples ◽

...

Keyword(s):

Lolium Multiflorum ◽

Acetolactate Synthase ◽

Target Site ◽

Italian Ryegrass ◽

Integrated Weed Management ◽

Multiple Resistance ◽

Acetyl Coa Carboxylase ◽

Acetyl Coa ◽

Alopecurus Myosuroides ◽

Target Site Resistance

Understanding the resistance spectrum and underlying genetic mechanisms is critical for managing herbicide-resistant populations. In this study, resistance to acetyl CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibitors was investigated in four suspected resistant populations of Alopecurus myosuroides (ALOMY-001 to ALOMY-004) and Lolium multiflorum (LOLMU-001 to LOLMU-004), collected from cereal production fields in Ireland. Glasshouse assays with three ALOMY-active herbicides [propaquizafop, cycloxydim (ACCase) and mesosulfuron + iodosulfuron (ALS)] or five LOLMU-active herbicides [pinoxaden, propaquizafop, cycloxydim (ACCase) and mesosulfuron + iodosulfuron, pyroxsulam (ALS)], and target-site resistance mechanism studies, based on pyrosequencing, were carried out in each of those populations. For A. myosuroides, Ile-1781-Leu ACCase mutation contributed to propaquizafop and cycloxydim resistance (shoot dry weight GR50 resistance factor (RF) = 7.5–35.5) in all ALOMY populations, and the independent Pro-197-Thr or Pro-197-Ser ALS mutation contributed to mesosulfuron + iodosulfuron resistance (RF = 3.6–6.6), in ALOMY-002 to ALOMY-004. Most of the analyzed plants for these mutations were homo/heterozygous combinations or only heterozygous. For L. multiflorum, phenotypic resistance to mesosulfuron + iodosulfuron (RF = 11.9–14.6) and pyroxsulam (RF = 2.3–3.1) was noted in all LOLMU populations, but the Pro-197-Gln or Pro-197-Leu ALS mutation (mostly in homozygous status) was identified in LOLMU-001, LOLMU-002 and LOLMU-004 only. Additionally, despite no known ACCase mutations in any LOLMU populations, LOLMU-002 survived pinoxaden and propaquizafop application (RF = 3.4 or 1.3), and LOLMU-003 survived pinoxaden (RF = 2.3), suggesting the possibility of non-target-site resistance mechanisms for ACCase and/or ALS resistance in these populations. Different resistance levels, as evidenced by a reduction in growth as dose increased above field rates in ALOMY and LOLMU, were due to variations in mutation rate and the level of heterozygosity, resulting in an overall resistance rating of low to moderate. This is the first study confirming cross- and multiple resistance to ACCase- and ALS-inhibiting herbicides, highlighting that resistance monitoring in A. myosuroides and L. multiflorum in Ireland is critical, and the adoption of integrated weed management strategies (chemical and non-chemical/cultural strategies) is essential.

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Wheat (Triticum aestivum) Cultivar Tolerance and Italian Ryegrass (Lolium multiflorum) Control with Diclofop, BAY SMY 1500, and Metribuzin

Weed Technology ◽

10.1017/s0890037x00033844 ◽

1991 ◽

Vol 5 (4) ◽

pp. 776-781 ◽

Cited By ~ 10

Author(s):

David R. Shaw ◽

M. Todd Wesley

Keyword(s):

Lolium Multiflorum ◽

Wheat Yield ◽

Italian Ryegrass ◽

Silty Clay ◽

Application Timing ◽

Soft Red Winter Wheat ◽

Early Injury ◽

Winter Wheat Cultivars ◽

Tolerance Study ◽

Silty Clay Soil

In the field, 14 soft red winter wheat cultivars responded differently to 1.1 kg ai ha–1diclofop, 1.7 kg ai ha–1BAY SMY 1500, and 0.42 kg ai ha–1metribuzin applied POST. Diclofop and metribuzin did not injure any cultivar more than 10% on a silty clay soil. However, BAY SMY 1500 injured ‘Pioneer 2551’ and ‘Coker 983’ 39 and 21%, respectively, in March. All other cultivars were injured less than 10% by BAY SMY 1500. Early injury did not translate into yield loss in the cultivar tolerance study. In an application timing study for Italian ryegrass control, late-season ratings indicated better control with two-leaf applications than with PRE applications for all treatments. Delaying application to the three-tiller stage reduced control with BAY SMY 1500 or metribuzin, but not with diclofop. On the sandier soil at this location, wheat injury with 0.28 or 0.43 kg ha–1metribuzin or 2.2 kg ha–1BAY SMY 1500 was sufficient to reduce wheat yield compared with other treatments, despite good Italian ryegrass control.

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Winter Wheat Response to Preplant Applications of Aminocyclopyrachlor

Weed Technology ◽

10.1614/wt-d-10-00049.1 ◽

2011 ◽

Vol 25 (1) ◽

pp. 51-57 ◽

Cited By ~ 20

Author(s):

Andrew R. Kniss ◽

Drew J. Lyon

Keyword(s):

Winter Wheat ◽

Yield Loss ◽

Wheat Yield ◽

Field Studies ◽

Wheat Crop ◽

Yield Losses ◽

Fallow Period ◽

Winter Wheat Yield ◽

Winter Wheat Crop ◽

Preceding Winter

Field studies were conducted in Wyoming and Nebraska in 2007 through 2009 to evaluate winter wheat response to aminocyclopyrachlor. Aminocyclopyrachlor was applied at rates between 15 and 120 g ai ha−1 6, 4, and 2 mo before winter wheat planting (MBP). Redroot pigweed control was 90% with aminocyclopyrachlor rates of 111 and 50 g ha−1 when applied 4 or 2 MBP. Aminocyclopyrachlor at 37 g ha−1 controlled Russian thistle 90% when applied 6 MBP. At Sidney, NE, winter wheat yield loss was > 10% at all aminocyclopyrachlor rates when applied 2 or 4 MBP, and at all rates > 15 g ha−1 when applied 6 MBP. At Lingle, WY, > 40% winter wheat yield loss was observed at all rates when averaged over application timings. Although the maturing wheat plants looked normal, few seed were produced in the aminocyclopyrachlor treatments, and therefore preharvest wheat injury ratings of only 5% corresponded to yield losses ranging from 23 to 90%, depending on location. The high potential for winter wheat crop injury will almost certainly preclude the use of aminocyclopyrachlor in the fallow period immediately preceding winter wheat.

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Resistance Profile of Diclofop-Resistant Italian Ryegrass (Lolium multiflorum) to ACCase- and ALS-Inhibiting Herbicides in Arkansas, USA

Weed Science ◽

10.1614/ws-08-003.1 ◽

2008 ◽

Vol 56 (4) ◽

pp. 614-623 ◽

Cited By ~ 31

Author(s):

Yong In Kuk ◽

Nilda R. Burgos ◽

Robert C. Scott

Keyword(s):

Lolium Multiflorum ◽

Acetolactate Synthase ◽

Italian Ryegrass ◽

Cross Resistance ◽

Southern United States ◽

Resistance Pattern ◽

Acetyl Coa Carboxylase ◽

Wheat Production ◽

Resistant Accession ◽

Als Inhibitors

Diclofop-resistant Italian ryegrass is a major weed problem in wheat production. This study aimed to determine the resistance pattern of diclofop-resistant Italian ryegrass accessions from the southern United States to the latest commercialized herbicides for wheat production, pinoxaden and mesosulfuron, and to other acetolactate synthase (ALS) and acetyl-CoA carboxylase (ACCase) inhibitors. Twenty-nine of 36 accessions were resistant to the commercial dose of diclofop. The majority (80%) of diclofop-resistant accessions were also resistant to clodinafop. Of 25 diclofop-resistant accessions, 5 were resistant to pinoxaden. All accessions tested were susceptible to the commercial dose of clethodim and sethoxydim. The cross-resistance pattern of diclofop-resistant Italian ryegrass to other ACCase inhibitors was 20% for pinoxaden and none with clethodim or sethoxydim. One accession was resistant to mesosulfuron but not to diclofop. This mesosulfuron-resistant accession was cross-resistant to sulfometuron but not to imazamox. All diclofop-resistant accessions tested were susceptible to ALS inhibitors, mesosulfuron, sulfometuron, and imazamox. Therefore, diclofop-resistant Italian ryegrass in Arkansas can be controlled with imazamox (in Clearfield wheat) and can mostly be controlled with mesosulfuron and pinoxaden. It could also be controlled by other selective grass herbicides in broadleaf crops.

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Interference and Control of ALS-Resistant Mouse-Ear Cress (Arabidopsis thaliana) in Winter Wheat

Weed Technology ◽

10.1017/wet.2018.69 ◽

2018 ◽

Vol 32 (6) ◽

pp. 671-677

Author(s):

Ranjeet S. Randhawa ◽

James H. Westwood ◽

Charles W. Cahoon ◽

Michael L. Flessner

Keyword(s):

Winter Wheat ◽

Control Mouse ◽

Yield Loss ◽

Wheat Yield ◽

Acetolactate Synthase ◽

Potential Yield ◽

Resistant Mouse ◽

Greenhouse Trial ◽

Mouse Ear ◽

And Control

AbstractIn 2015, winter wheat growers in Virginia reported commercial failures of thifensulfuron to control mouse-ear cress. This was the first reported case of field-evolved acetolactate synthase (ALS) resistance in mouse-ear cress, so research was conducted to evaluate alternative herbicide options as well as to document potential yield loss in winter wheat from mouse-ear cress. Efficacy studies were conducted at three site-years in 2015 to 2016 and 2016 to 2017 as well as a POST greenhouse trial. In the PRE study, flumioxazin, pyroxasulfone, saflufenacil, and metribuzin resulted in more than 80% mouse-ear cress control 15 wk after planting across all sites with no observable wheat injury. No differences were observed in wheat yield in two of three sites in the PRE herbicide study; yield differences were attributed to common chickweed and not to mouse-ear cress. In the POST herbicide study, 2,4-D, dicamba, and metribuzin resulted in greater than 75% control in the field and greenhouse. Metribuzin, dicamba, and pyroxsulam resulted in crop injury 3 wk after treatment at some sites, but injury was transient. Yield from all POST treatments was similar to the nontreated plots. No yield loss was observed by mouse-ear cress densities greater than 300 plants m–2, indicating that mouse-ear cress is not very competitive with winter wheat. Growers should make herbicide decisions based on other weeds in the field and can incorporate the aforementioned herbicides for mouse-ear cress control.

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A Survey for Diclofop-Methyl Resistance in Italian Ryegrass from Tennessee and How To Manage Resistance in Wheat

Weed Technology ◽

10.1614/wt-d-09-00035.1 ◽

2010 ◽

Vol 24 (3) ◽

pp. 303-309 ◽

Cited By ~ 21

Author(s):

Andrew T. Ellis ◽

Lawrence E. Steckel ◽

Christopher L. Main ◽

Marcel S. C. De Melo ◽

Dennis R. West ◽

...

Keyword(s):

Field Experiments ◽

Wheat Yield ◽

Acetolactate Synthase ◽

The United States ◽

Research Field ◽

Italian Ryegrass ◽

Cross Resistance ◽

Susceptible Population ◽

Application Timing ◽

Herbicide Programs

Italian ryegrass resistance to diclofop has been documented in several countries, including the United States. The purpose of this research was to screen selected putative resistant populations of Italian ryegrass for resistance to the acetyl-CoA carboxylase (ACCase)–inhibiting herbicides diclofop and pinoxaden and the acetolactate synthase (ALS)–inhibiting herbicides imazamox, pyroxsulam, and mesosulfuron in the greenhouse and to use field experiments to develop herbicide programs for Italian ryegrass control. Resistance to diclofop was confirmed in eight populations from Tennessee. These eight populations did not show cross-resistance to pinoxaden. One additional population (R1) from Union County, North Carolina, was found to be resistant to both diclofop and pinoxaden. The level of resistance to pinoxaden of the R1 population was 15 times that of the susceptible population. No resistance was confirmed to any of the ALS-inhibiting herbicides examined in this research. Field experiments demonstrated PRE Italian ryegrass control with chlorsulfuron (71 to 94%) and flufenacet + metribuzin (84 to 96%). Italian ryegrass control with pendimethalin applied PRE or delayed preemergence (DPRE) was variable (0 to 85%). POST control of Italian ryegrass was acceptable with pinoxaden, mesosulfuron, flufenacet + metribuzin, and chlorsulfuron + flucarbazone (> 80%). Application timing and herbicide treatment had no effect on wheat yield, except for diclofop and pendimethalin treatments, in which uncontrolled Italian ryegrass reduced wheat yield.

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