INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
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Herbicide Resistant Rigid Ryegrass Globally
(Lolium rigidum)
Herbicide Resistant Rigid Ryegrass Globally
(Lolium rigidum)
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Herbicide Resistant Rigid Ryegrass Globally
(Lolium rigidum)
#CountryFirstYearSituationActive IngredientsSite of Action
1 AlgeriaAlgeria 2023 Wheat clodinafop-propargyl, and pinoxaden 115 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass29273
2 AlgeriaAlgeria 2023 Wheat iodosulfuron-methyl-Na, mesosulfuron-methyl, and pyroxsulam 115 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass29274
3 AlgeriaAlgeria 2023 Wheat clodinafop-propargyl, iodosulfuron-methyl-Na, mesosulfuron-methyl, pinoxaden, and pyroxsulam 115 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass29277
4 Australia (Western Australia) AustraliaWestern Australia1982 Canola, Spring Barley, and Wheat chlorsulfuron, diclofop-methyl, fluazifop-butyl, sethoxydim, tralkoxydim, and trifluralin 1 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
 		112Lolium rigidumRigid Ryegrass15
5 Australia (South Australia) AustraliaSouth Australia1982 Spring Barley, and Wheat chlorpropham, chlorsulfuron, clomazone, diclofop-methyl, ethalfluralin, fluazifop-butyl, imazapyr, metolachlor, metsulfuron-methyl, quizalofop-ethyl, sethoxydim, tralkoxydim, tri-allate, triasulfuron, and trifluralin 1 Multiple Resistance: 6 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Deoxy-D-Xylulose Phosphate SynthaseHRAC Group 13 (Legacy F4)
Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
Inhibition of Microtubule Organization HRAC Group 23 (Legacy K2)
Very Long-Chain Fatty Acid Synthesis inhibitorsHRAC Group 15 (Legacy K3 N)
 		112Lolium rigidumRigid Ryegrass389
6 Australia (Western Australia) AustraliaWestern Australia1984 Cropland, Spring Barley, and Wheat chlorsulfuron, and metsulfuron-methyl 1 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass324
7 Australia (Western Australia) AustraliaWestern Australia1984 Cropland, and Pasture seed trifluralin 1 Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
 		112Lolium rigidumRigid Ryegrass330
8 Australia (South Australia) AustraliaSouth Australia1984 Cropland metolachlor 1 Very Long-Chain Fatty Acid Synthesis inhibitorsHRAC Group 15 (Legacy K3 N)
 		112Lolium rigidumRigid Ryegrass398
9 Australia (Victoria) AustraliaVictoria1984 Pastures, Spring Barley, and Wheat chlorsulfuron, diclofop-methyl, fluazifop-butyl, metsulfuron-methyl, quizalofop-ethyl, sethoxydim, and trifluralin 1 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
 		112Lolium rigidumRigid Ryegrass5042
10 Australia (New South Wales ) AustraliaNew South Wales 1985 Canola, Chickpea, Faba beans, Lentils, Lupins, Peas, Spring Barley, and Wheat chlorsulfuron, diclofop-methyl, fluazifop-butyl, haloxyfop-methyl, metsulfuron-methyl, quizalofop-ethyl, sethoxydim, tralkoxydim, triasulfuron, and trifluralin 1 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
 		112Lolium rigidumRigid Ryegrass4
11 Australia (Western Australia) AustraliaWestern Australia1988 Railways, and Roadsides amitrole 1 Inhibition of Lycopene Cyclase HRAC Group 34 (Legacy F3)
 		112Lolium rigidumRigid Ryegrass316
12 Australia (Western Australia) AustraliaWestern Australia1988 Cropland, Pasture seed, Railways, Roadsides, and Triazine-tolerant canola atrazine, and simazine 1 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		112Lolium rigidumRigid Ryegrass480
13 Australia (South Australia) AustraliaSouth Australia1994 Cereals trifluralin 1 Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
 		112Lolium rigidumRigid Ryegrass5226
14 Australia (Victoria) AustraliaVictoria1996 Canola, Cereals, Fencelines, and Wheat glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass380
15 Australia (New South Wales ) AustraliaNew South Wales 1997 Apples, Around Buildings, Canola, Cereals, Fencelines, Irrigation Channels, Roadsides, and Wheat glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5094
16 Australia (South Australia) AustraliaSouth Australia1999 Alfalfa, Cereals, Clover, Fencelines, Grapes, Irrigation Channels, and Roadsides glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5188
17 Australia (Victoria) AustraliaVictoria1999 Wheat chlorsulfuron, diclofop-methyl, glyphosate, and trifluralin 1 Multiple Resistance: 4 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
 		112Lolium rigidumRigid Ryegrass5363
18 Australia (Western Australia) AustraliaWestern Australia2003 Cereals, Fencelines, Grapes, Railways, and Roadsides glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5325
19 Australia (South Australia) AustraliaSouth Australia2008 Grapes amitrole, and glyphosate 1 Multiple Resistance: 2 Sites of Action
Inhibition of Lycopene Cyclase HRAC Group 34 (Legacy F3)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5515
20 Australia (South Australia) AustraliaSouth Australia2010 Pasture seed clethodim, and paraquat 1 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
PS I Electron Diversion HRAC Group 22 (Legacy D)
 		112Lolium rigidumRigid Ryegrass5489
21 Australia (South Australia) AustraliaSouth Australia2010 Pasture seed atrazine, chlorsulfuron, clethodim, glyphosate, haloxyfop-methyl, imazapyr, iodosulfuron-methyl-Na, and paraquat 1 Multiple Resistance: 5 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
PS I Electron Diversion HRAC Group 22 (Legacy D)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5510
22 Australia (Western Australia) AustraliaWestern Australia2013 Grapes glyphosate, and paraquat 1 Multiple Resistance: 2 Sites of Action
PS I Electron Diversion HRAC Group 22 (Legacy D)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass6754
23 Australia (Victoria) AustraliaVictoria2015 Wheat tri-allate 1 Very Long-Chain Fatty Acid Synthesis inhibitorsHRAC Group 15 (Legacy K3 N)
 		112Lolium rigidumRigid Ryegrass11023
24 Australia (New South Wales ) AustraliaNew South Wales 2015 Wheat tri-allate 1 Very Long-Chain Fatty Acid Synthesis inhibitorsHRAC Group 15 (Legacy K3 N)
 		112Lolium rigidumRigid Ryegrass11031
25 ChileChile 1997 Canola, Cereals, Lupins, Spring wheat, and Winter wheat clethodim, clodinafop-propargyl, diclofop-methyl, haloxyfop-methyl, sethoxydim, and tralkoxydim 8 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass5102
26 ChileChile 2003 Wheat clethodim, clodinafop-propargyl, diclofop-methyl, flucarbazone-Na, haloxyfop-methyl, iodosulfuron-methyl-Na, pinoxaden, and tepraloxydim 8 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass5427
27 FranceFrance 1993 Wheat diclofop-methyl 17 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass550
28 FranceFrance 2005 Cereals, Grapes, Orchards, and Rapeseed glyphosate 17 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5285
29 FranceFrance 2006 Wheat flupyrsulfuron-methyl-Na, iodosulfuron-methyl-Na, mesosulfuron-methyl, and propoxycarbazone-Na 17 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass5330
30 GreeceGreece 1997 Winter wheat diclofop-methyl 19 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass553
31 GreeceGreece 2009 Winter wheat chlorsulfuron 19 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass13053
32 GreeceGreece 2016 Orchards glyphosate 19 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass17137
33 GreeceGreece 2017 Grapes, Olive, and Orchards glufosinate-ammonium 19 Inhibition of Glutamine Synthetase HRAC Group 10 (Legacy H)
 		112Lolium rigidumRigid Ryegrass17136
34 IranIran 2007 Winter wheat clodinafop-propargyl, diclofop-methyl, and pinoxaden 79 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass5340
35 IsraelIsrael 1979 Orchards, and Roadsides atrazine, and simazine 23 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		112Lolium rigidumRigid Ryegrass97
36 IsraelIsrael 1998 Alfalfa, and Wheat clodinafop-propargyl, diclofop-methyl, pinoxaden, and quizalofop-ethyl 23 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass5109
37 IsraelIsrael 2007 Wheat chlorsulfuron, clodinafop-propargyl, florasulam, flumetsulam, glyphosate, imazapyr, iodosulfuron-methyl-Na, mesosulfuron-methyl, metosulam, pinoxaden, propoxycarbazone-Na, sulfometuron-methyl, and tribenuron-methyl 23 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5556
38 IsraelIsrael 2013 Carrots, and Wheat clethodim, clodinafop-propargyl, cycloxydim, haloxyfop-methyl, iodosulfuron-methyl-Na, mesosulfuron-methyl, pinoxaden, propoxycarbazone-Na, and sulfometuron-methyl 23 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass10992
39 ItalyItaly 2007 Grapes, and Orchards glyphosate 24 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5370
40 MoroccoMorocco 2023 Wheat clodinafop-propargyl, and pinoxaden 166 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass29271
41 MoroccoMorocco 2023 Wheat iodosulfuron-methyl-Na, mesosulfuron-methyl, and pyroxsulam 166 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass29272
42 MoroccoMorocco 2023 Wheat clodinafop-propargyl, iodosulfuron-methyl-Na, mesosulfuron-methyl, pinoxaden, and pyroxsulam 166 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass29278
43 Saudi ArabiaSaudi Arabia 1992 Cereals, and Wheat clodinafop-propargyl, diclofop-methyl, and tralkoxydim 35 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass551
44 South AfricaSouth Africa 1993 Wheat clodinafop-propargyl, diclofop-methyl, fluazifop-butyl, haloxyfop-methyl, imazamox, sethoxydim, and tralkoxydim 37 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass192
45 South AfricaSouth Africa 2001 Grapes glyphosate 37 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5093
46 South AfricaSouth Africa 2002 Fruit, and Grapes paraquat 37 PS I Electron Diversion HRAC Group 22 (Legacy D)
 		112Lolium rigidumRigid Ryegrass5119
47 South AfricaSouth Africa 2003 Grapes glyphosate, haloxyfop-methyl, paraquat, and tepraloxydim 37 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
PS I Electron Diversion HRAC Group 22 (Legacy D)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5239
48 SpainSpain 1992 Wheat chlorotoluron, and diclofop-methyl 38 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		112Lolium rigidumRigid Ryegrass172
49 SpainSpain 1992 Wheat diclofop-methyl 38 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass173
50 SpainSpain 1992 Orchards simazine 38 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		112Lolium rigidumRigid Ryegrass174
51 SpainSpain 2006 Orchards glyphosate 38 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass5332
52 SpainSpain 2015 Wheat, and Winter barley clethodim, diclofop-methyl, florasulam, iodosulfuron-methyl-Na, mesosulfuron-methyl, and pyroxsulam 38 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass31272
53 SpainSpain 2016 Olive glyphosate, and oxyfluorfen 38 Multiple Resistance: 2 Sites of Action
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass17105
54 TunisiaTunisia 1996 Cereals diclofop-methyl 78 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		112Lolium rigidumRigid Ryegrass5028
55 TunisiaTunisia 2023 Wheat iodosulfuron-methyl-Na, mesosulfuron-methyl, and pyroxsulam 78 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass29275
56 TunisiaTunisia 2023 Wheat clodinafop-propargyl, iodosulfuron-methyl-Na, mesosulfuron-methyl, and pinoxaden 78 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		112Lolium rigidumRigid Ryegrass29276
57 United States (California) United StatesCalifornia1998 Almonds, and Orchards glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		112Lolium rigidumRigid Ryegrass1034
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