Herbicide Resistant Weeds

GROUP A/1 RESISTANT ITALIAN RYEGRASS (Lolium multiflorum)
France

Tuesday, September 07, 2010

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Italian Ryegrass

1.	Introduction
2.	Level of Infestation
3.	Quick Statistics
4.	Notes about this biotype
5.	Academic Aspects
6.	R Italian Ryegrass Globally
7.	Fact Sheets and Literature
8.	Contributing Weed Scientists
9.	Acknowledgements
10.	Where to now?

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Introduction

Level of Infestation

Italian Ryegrass (Lolium multiflorum) is a monocot weed in the Poaceae family. In France this weed first evolved resistance to Group A/1 herbicides in 1993 and infests wheat. Group A/1 herbicides are known as ACCase inhibitors (Inhibition of acetyl CoA carboxylase (ACCase)). Research has shown that these particular biotypes are resistant to diclofop-methyl and they may be cross-resistant to other Group A/1 herbicides.

Local weed scientists estimate that Group A/1 resistant Italian Ryegrass in France infests unknown sites and the number of sites are increasing. They also estimate that there are unknown acres infested with Group A/1 resistant Italian Ryegrass and the area infested is increasing.

The 'Group' letters/numbers that you see throughout this web site refer to the classification of herbicides by their mode of action. To see a full list of herbicides and HRAC herbicide classifications click here.

QUIK STATS ( last updated Nov 19, 2000 )
Common Name	Italian Ryegrass
Species	Lolium multiflorum
Group	ACCase inhibitors (A/1)
Herbicides	diclofop-methyl
Location	France
Year	1993
Situation(s)	wheat
Sites	unknown
Acres Infested	unknown
Contributors	Jacques Gasquez
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NOTES ABOUT THIS BIOTYPE

AREAS FOUND

Jacques Gasquez

In the North of France, in the South West and in the South East.

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GENERAL

Jacques Gasquez

As for blackgrass the resistant populations of this weed have increased since 1993. We know that there are target mutation and detoxification, but, up to now, each one in different populations. The major problem with this weed is the identification. In France there are three highly outcrossing species, Lolium perenne, Lolium multiflorum, and Lolium rigidum. Furthermore many varieties have been used which interbred with the wild plants. So it is almost impossible to be sure that a given plant belongs to one of these species. The plants are all annual. Generally the plants growing in the North of France are Lolium multiflorum and in the South east Lolium rigidum. But in many cases there is no way to give a botanical name.

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ACADEMIC ASPECTS

Confirmation Tests

Field, Greenhouse, and Laboratory trials comparing a known susceptible Italian Ryegrass biotype with this Italian Ryegrass 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

The genetic basis of resistance for this biotype is either unknown or has not been entered in the database. If you know anything about the genetic inheritance of this biotype please update the database.

Mechanism of Resistance

Studies on the mechanism of resistance of Group A/1 resistant Italian Ryegrass from France indicate that resistance is due to an altered target site, and enhanced metabolism. There may be a note below or an article discussing the mechanism of resistance in the "Fact Sheets and Other Literature"

Relative Fitness

There is no record of differences in fitness or competitiveness of these resistant biotypes when compared to that of normal susceptible biotypes. If you have any information pertaining to the fitness of Group A/1 resistant Italian Ryegrass from France please update the database.

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HERBICIDE RESISTANT ITALIAN RYEGRASS GLOBALLY
#	Country	Year	Sites	Acres	Mode of Action
1.	Argentina	2007	2-5	51-100	Glycines (G/9)
2.	Brazil	2003	2-5	51-100	Glycines (G/9)
3.	Chile	1998	11-50	1001-10000	ACCase inhibitors (A/1)
4.	Chile	2001	2-5	101-500	Glycines (G/9)
5.	Chile	2002	2-5	unknown	Glycines (G/9)
6.	Chile Multiple Resistance	2002	1	11-50	ALS inhibitors (B/2) Glycines (G/9)
7.	Chile	2004	1	101-500	ACCase inhibitors (A/1)
8.	Chile Multiple Resistance	2005	1	51-100	ACCase inhibitors (A/1) ALS inhibitors (B/2)
9.	Chile Multiple Resistance	2005	1	101-500	ACCase inhibitors (A/1) ALS inhibitors (B/2)
10.	Chile Multiple Resistance	2005	1	11-50	ACCase inhibitors (A/1) ALS inhibitors (B/2)
11.	Chile Multiple Resistance	2006	1	51-100	ACCase inhibitors (A/1) ALS inhibitors (B/2)
12.	Chile Multiple Resistance	2006	1	101-500	ACCase inhibitors (A/1) ALS inhibitors (B/2)
13.	Chile Multiple Resistance	2006	1	51-100	ACCase inhibitors (A/1) ALS inhibitors (B/2)
14.	Chile Multiple Resistance	2006	1	11-50	ACCase inhibitors (A/1) ALS inhibitors (B/2)
15.	Chile Multiple Resistance	2006	1	51-100	ACCase inhibitors (A/1) Glycines (G/9)
16.	Chile Multiple Resistance	2007	1	51-100	ACCase inhibitors (A/1) ALS inhibitors (B/2) Glycines (G/9)
17.	France	1993	unknown	unknown	ACCase inhibitors (A/1)
18.	Italy	1995	51-100	10001-100000	ACCase inhibitors (A/1)
19.	Spain	2006	2-5	101-500	Glycines (G/9)
20.	United Kingdom	1990	51-100	101-500	ACCase inhibitors (A/1)
21.	United Kingdom	1990	11-50	unknown	Ureas and amides (C2/7)
22.	USA (Oregon)	1987	101-500	1001-10000	ACCase inhibitors (A/1)
23.	USA (North Carolina)	1990	501-1000	10001-100000	ACCase inhibitors (A/1)
24.	USA (South Carolina)	1990	101-500	1001-10000	ACCase inhibitors (A/1)
25.	USA (Idaho)	1991	101-500	10001-100000	ACCase inhibitors (A/1)
26.	USA (Virginia)	1993	501-1000	10001-100000	ACCase inhibitors (A/1)
27.	USA (Mississippi)	1995	51-100	101-500	ALS inhibitors (B/2)
28.	USA (Georgia)	1995	6-10	101-500	ACCase inhibitors (A/1)
29.	USA (Arkansas) Multiple Resistance	1995	51-100	1001-10000	ACCase inhibitors (A/1) ALS inhibitors (B/2)
30.	USA (Maryland)	1998	unknown	unknown	ACCase inhibitors (A/1)
31.	USA (Arkansas)	2003	1	11-50	ALS inhibitors (B/2)
32.	USA (Oregon)	2004	1	1-5	Glycines (G/9)
33.	USA (Idaho) Multiple Resistance	2005	101-500	1001-10000	ACCase inhibitors (A/1) ALS inhibitors (B/2) Chloroacetamides and others (K3/15)
34.	USA (Mississippi)	2005	unknown	1001-10000	Glycines (G/9)
35.	USA (Arkansas)	2005	11-50	501-1000	ACCase inhibitors (A/1)
36.	USA (Tennessee)	2006	51-100	1001-10000	ACCase inhibitors (A/1)
37.	USA (Arkansas) Multiple Resistance	2008	6-10	101-500	ACCase inhibitors (A/1) ALS inhibitors (B/2)
38.	USA (Arkansas)	2008	11-50	1001-10000	Glycines (G/9)

FACT SHEETS AND OTHER LITERATURE	Format
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Scientific Abstracts on Herbicide Resistant Lolium multiflorum
Diclofop-methyl resistance in populations of Lolium spp. from central Italy.
Bravin, F., G. Zanin and C. Preston 2001. Diclofop-methyl resistance in populations of Lolium spp. from central Italy. Weed Research. 41: 49-58.
Resistance to diclofop-methyl in two Lolium spp. populations from Italy: studies on the mechanism of resistance.
Bravin, F., G. Zanin and C. Preston 2001. Resistance to diclofop-methyl in two Lolium spp. populations from Italy: studies on the mechanism of resistance. Weed Research. 41: 461-473.
The occurrence of herbicide-resistant grass-weeds in the United Kingdom and a new system for designating resistance in screening assays.
Moss, S. R., J. Clarke H., A. Blair M., T. Culley N., M. Read A., P. Ryan J., and M. Turner. 1999. The occurrence of herbicide-resistant grass-weeds in the United Kingdom and a new system for designating resistance in screening assays. 1999 Brighton crop protection conference: weeds. Proceedings of an international conference, Brighton, UK, 15-18 November 1999. 1: 179-184.
Evolution of resistance to diclofop-methyl in ryegrass (Lolium multiflorum): investigation of the role of introgression with related species.
Martinez Ghersa, M. A., C. Ghersa M., M. Vila Aiub M., E. Satorre H., and S. Radosevich R. 1997. Evolution of resistance to diclofop-methyl in ryegrass (Lolium multiflorum): investigation of the role of introgression with related species. Pesticide Science. 51: 305-308.
Isoforms of acetyl-coenzyme A carboxylase in Lolium multiflorum.
Evenson, K. J., J. W. Gronwald, and D. L. Wyse. 1997. Isoforms of acetyl-coenzyme A carboxylase in Lolium multiflorum. Plant Physiology and Biochemistry Paris. 35: 265-272.
Registration of ORARHR-G93 and ORARHR-M93 Italian ryegrass germplasm with tolerance to diclofop-methyl.
Barker, R. E., G. Mueller Warrant W., G. Banowetz M., M. Roush L., B. Maxwell D., S. Griffith M., and S. Radosevich R. 1997. Registration of ORARHR-G93 and ORARHR-M93 Italian ryegrass germplasm with tolerance to diclofop-methyl. Crop Science. 37: 1035.
Revised guidelines for preventing and managing herbicide-resistant grass-weeds.
Anon. 1997. Revised guidelines for preventing and managing herbicide-resistant grass-weeds. Revised guidelines for preventing and managing herbicide resistant grass weeds. : 8.
Identification of sulfometuron-resistant Italian ryegrass (Lolium multiflorum) selections.
Taylor, J. M. and G. E. Coats. 1996. Identification of sulfometuron-resistant Italian ryegrass (Lolium multiflorum) selections. Weed Technology. 10: 943-946.
Comparison of fall versus spring applications of sulfometuron for common bermudagrass (Cynodon dactylon) release.
Taylor, J. M. and G. E. Coats. 1996. Comparison of fall versus spring applications of sulfometuron for common bermudagrass (Cynodon dactylon) release. Weed Technology. 10: 947-950.
Selection pressures for diclofop-methyl resistance and germination time of Italian ryegrass.
Ghersa, C. M., M. A. Martinez Ghersa, T. G. Brewer, and M. L. Roush. 1994. Selection pressures for diclofop-methyl resistance and germination time of Italian ryegrass. Agronomy Journal. 86: 823-828.
Purification and characterization of acetyl-coenzyme A carboxylase from diclofop-resistant and -susceptible Lolium multiflorum.
Evenson, K. J., J. W. Gronwald, and D. L. Wyse. 1994. Purification and characterization of acetyl-coenzyme A carboxylase from diclofop-resistant and -susceptible Lolium multiflorum. Plant Physiology. 105: 671-680.
Use of gene flow to control diclofop-methyl resistance in Italian ryegrass (Lolium multiflorum).
Ghersa, C. M., M. A. Martinez Ghersa, T. G. Brewer, and M. L. Roush. 1994. Use of gene flow to control diclofop-methyl resistance in Italian ryegrass (Lolium multiflorum). Weed Technology. 8: 139-147.
The influence of the biology and ecology of Italian ryegrass on the evolution of herbicide resistance.
Heap, I. and R. G. Lym. 1993. The influence of the biology and ecology of Italian ryegrass on the evolution of herbicide resistance. Proceedings of the Western Society of Weed Science, Tucson, Arizona, USA, 9-11 March 1993. 46: 122-126.
Implications of herbicide resistant Lolium multiflorum (Italian rye-grass).
Moss, S. R., J. Horswell, R. J. Froud Williams, and M. M. Ndoping. 1993. Implications of herbicide resistant Lolium multiflorum (Italian rye-grass). Aspects of Applied Biology. 35: 53-60.
Target site-based resistance to herbicides inhibiting acetyl-CoA carboxylase.
Tardif, F. J. and S. B. Powles. 1993. Target site-based resistance to herbicides inhibiting acetyl-CoA carboxylase. Brighton crop protection conference, weeds. Proceedings of an international conference, Brighton, UK, 22-25 November 1993. 2: 533-540.
Mechanism of inheritance of diclofop resistance in Italian ryegrass (Lolium multiflorum).
Betts, K. J., N. J. Ehlke, D. L. Wyse, J. W. Gronwald, and D. A. Somers. 1992. Mechanism of inheritance of diclofop resistance in Italian ryegrass (Lolium multiflorum). Weed Science. 40: 184-189.
Mechanism of diclofop resistance in an Italian ryegrass (Lolium multiflorum Lam.) biotype.
Gronwald, J. W., C. V. Eberlein, K. J. Betts, R. J. Baerg, N. J. Ehlke, and D. L. Wyse. 1992. Mechanism of diclofop resistance in an Italian ryegrass (Lolium multiflorum Lam.) biotype. Pesticide Biochemistry and Physiology. 44: 126-139.
Diclofop-resistance in a Lolium multiflorum biotype from Oregon.
Gronwald, J. W., K. C. Betts, N. J. Ehlke, and D. L. Wyse. 1992. Diclofop-resistance in a Lolium multiflorum biotype from Oregon. Proceedings of the 1st International Weed Control Congress. 2: 189-191.
Cross-resistance to herbicides in annual ryegrass (Lolium rigidum) . I. Properties of the herbicide target enzymes acetyl-coenzyme A carboxylase and acetolactate synthase.
Matthews, J. M., J. A. M. Holtum, D. R. Liljegren, B. Furness, and S. B. Powles. 1990. Cross-resistance to herbicides in annual ryegrass (Lolium rigidum) . I. Properties of the herbicide target enzymes acetyl-coenzyme A carboxylase and acetolactate synthase. Plant Physiology. 94: 1180-1186.
Italian ryegrass (Lolium multiflorum) accessions tolerant to diclofop.
Stanger, C. E. and A. P. Appleby. 1989. Italian ryegrass (Lolium multiflorum) accessions tolerant to diclofop. Weed Science. 37: 350-353.

CONTRIBUTING WEED SCIENTISTS

JACQUES GASQUEZ	Edit
INRA Laboratoire de Malherbologie BV 1540 Dijon, 21034, Cedex France Email Jacques Gasquez

Acknowledgements

Where to now?

The Herbicide Resistance Action Committee, the Weed Science Society of America, and weed scientists in France have been instrumental in providing you this information. Particular thanks is given to Jacques Gasquez for providing detailed information.

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