International Survey of Herbicide-Resistant Weeds

Countries Weeds Herbicides Mutations Graphs References Researchers
Most Recent Cases of Herbicide Resistant Weeds Entered into the Database
(click on a column header to sort or click on a country for details)
#Date Last UpdatedSpeciesCountryFirst YearSite of Action
1 December 6, 2025Ischaemum rugosumBrazilBrazil 20245 Inhibition of Acetolactate Synthase (B/2)
99Saramollagrass33276
2 November 24, 2025Poa annuaUnited States (Oregon) United StatesOregon202545 Inhibition of Microtubule Assembly (K1/3)
130Annual Bluegrass33279
3 November 24, 2025Poa annuaUnited States (Oregon) United StatesOregon202545 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
130Annual Bluegrass33281
4 November 24, 2025Poa annuaUnited States (Oregon) United StatesOregon202545 PS I Electron Diversion (D/22)
130Annual Bluegrass33280
5 November 24, 2025Poa annuaUnited States (Oregon) United StatesOregon202545 Inhibition of Acetyl CoA Carboxylase (A/1)
130Annual Bluegrass33278
6 November 24, 2025Poa annuaUnited States (Oregon) United StatesOregon202545 Inhibition of Cellulose Synthesis (L/29)
130Annual Bluegrass33277
7 November 8, 2025Amaranthus palmeriUnited States (North Carolina) United StatesNorth Carolina202545 Multiple Resistance: 5 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
Auxin Mimics (O/4)
14Palmer Amaranth33275
8 October 9, 2025Helianthus annuusMexicoMexico 202329 Inhibition of Acetolactate Synthase (B/2)
95Common Sunflower32283
9 October 9, 2025Digitaria sanguinalisFranceFrance 202317 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
77Large Crabgrass32286
10 October 9, 2025Echinochloa crus-galli var. crus-galliFranceFrance 201717 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
79Barnyardgrass32285
11 August 28, 2025Eleusine indicaUnited States (North Carolina) United StatesNorth Carolina202245 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
81Goosegrass32279
12 August 19, 2025Lolium rigidumAlgeriaAlgeria 2023115 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
112Rigid Ryegrass29277
13 August 19, 2025Lolium rigidumTunisiaTunisia 202378 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
112Rigid Ryegrass29276
14 August 19, 2025Lolium rigidumMoroccoMorocco 2023166 Inhibition of Acetolactate Synthase (B/2)
112Rigid Ryegrass29272
15 August 19, 2025Lolium rigidumMoroccoMorocco 2023166 Inhibition of Acetyl CoA Carboxylase (A/1)
112Rigid Ryegrass29271
16 August 19, 2025Lolium rigidumMoroccoMorocco 2023166 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
112Rigid Ryegrass29278
17 August 19, 2025Papaver rhoeasTunisiaTunisia 202578 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Auxin Mimics (O/4)
123Corn Poppy32278
18 August 19, 2025Papaver rhoeasMoroccoMorocco 2025166 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Auxin Mimics (O/4)
123Corn Poppy32277
19 August 18, 2025Arctotheca calendulaAustralia (Western Australia) AustraliaWestern Australia20211 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
21Capeweed32276
20 August 18, 2025Kochia scopariaUnited States (South Dakota) United StatesSouth Dakota202345 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
101Kochia32275
21 July 30, 2025Amaranthus palmeriUnited States (Arkansas) United StatesArkansas202345 Auxin Mimics (O/4)
14Palmer Amaranth32271
22 July 25, 2025Lolium perenne ssp. multiflorumUnited States (New York) United StatesNew York202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
110Italian Ryegrass32273
23 July 24, 2025Kochia scopariaArgentinaArgentina 202348 Inhibition of Acetolactate Synthase (B/2)
101Kochia31277
24 July 24, 2025Daucus carotaNew ZealandNew Zealand 202530 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
76Wild Carrot32274
25 July 24, 2025Stellaria mediaEstoniaEstonia 202199 Inhibition of Acetolactate Synthase (B/2)
168Common Chickweed30270
26 July 24, 2025Amaranthus palmeriUnited States (North Carolina) United StatesNorth Carolina202545 Inhibition of Protoporphyrinogen Oxidase (E/14)
14Palmer Amaranth32272
27 July 23, 2025Amaranthus palmeriItalyItaly 201824 Inhibition of Acetolactate Synthase (B/2)
14Palmer Amaranth32268
28 June 5, 2025Poa trivialisIrelandIreland 202381 Inhibition of Acetolactate Synthase (B/2)
350Roughstalk Bluegrass31279
29 May 30, 2025Panicum dichotomiflorumSpainSpain 202238 Inhibition of Acetolactate Synthase (B/2)
122Fall Panicum31276
30 May 30, 2025Kochia scopariaSpainSpain 202238 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
Auxin Mimics (O/4)
101Kochia31275
31 May 30, 2025Conyza sumatrensisBoliviaBolivia 20244 PS I Electron Diversion (D/22)
65Sumatran Fleabane31271
32 May 30, 2025Rapistrum rugosumArgentinaArgentina 201848 Inhibition of Acetolactate Synthase (B/2)
142Turnipweed31273
33 May 22, 2025Amaranthus palmeriArgentinaArgentina 202548 Inhibition of Protoporphyrinogen Oxidase (E/14)
14Palmer Amaranth31274
34 April 24, 2025Conyza canadensisMexicoMexico 201829 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
61Horseweed31270
35 March 3, 2025Polygonum convolvulus (=Fallopia convolvulus)United States (Kansas) United StatesKansas202045 Inhibition of Acetolactate Synthase (B/2)
88Wild Buckwheat31269
36 February 24, 2025Brassica rapa (=B. campestris)MexicoMexico 202129 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
Auxin Mimics (O/4)
36Birdsrape Mustard31268
37 January 27, 2025Amaranthus palmeriUnited States (New York) United StatesNew York202445 Multiple Resistance: 2 Sites of Action
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth30269
38 January 27, 2025Conyza canadensisUnited States (New York) United StatesNew York202445 PS I Electron Diversion (D/22)
61Horseweed30268
39 December 7, 2024Amaranthus palmeriTurkeyTurkey 202371 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth29268
40 December 5, 2024Steinchisma laxumColombiaColombia 202310 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
1358Lax Panicgrass27271
41 December 2, 2024Setaria viridisUkraineUkraine 2024230 Inhibition of Acetolactate Synthase (B/2)
153Green Foxtail29269
42 November 27, 2024Alopecurus myosuroidesFranceFrance 202217 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
6Blackgrass29265
43 November 6, 2024Lolium rigidumTunisiaTunisia 202378 Inhibition of Acetolactate Synthase (B/2)
112Rigid Ryegrass29275
44 October 24, 2024Atriplex patulaFranceFrance 201917 PSII inhibitors - Serine 264 Binders (C1 C2/5)
26Halberdleaf Orach29266
45 October 10, 2024Lolium rigidumAlgeriaAlgeria 2023115 Inhibition of Acetolactate Synthase (B/2)
112Rigid Ryegrass29274
46 October 10, 2024Lolium rigidumAlgeriaAlgeria 2023115 Inhibition of Acetyl CoA Carboxylase (A/1)
112Rigid Ryegrass29273
47 October 9, 2024Galium spuriumAustriaAustria 20242 Inhibition of Acetolactate Synthase (B/2)
93False Cleavers29264
48 September 23, 2024Echinochloa colonaPakistanPakistan 202486 Inhibition of Acetolactate Synthase (B/2)
78Junglerice29279
49 September 17, 2024Amaranthus albusIsraelIsrael 202323 Inhibition of Acetolactate Synthase (B/2)
7Tumble Pigweed29280
50 September 5, 2024Avena fatuaPakistanPakistan 202486 Inhibition of Acetyl CoA Carboxylase (A/1)
28Wild Oat29281
51 August 29, 2024Amaranthus palmeriUnited States (Kansas) United StatesKansas202145 Multiple Resistance: 6 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
Auxin Mimics (O/4)
14Palmer Amaranth24257
52 August 24, 2024Alopecurus myosuroidesFranceFrance 202017 Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
6Blackgrass29267
53 August 11, 2024Schoenoplectus juncoidesChinaChina 20249 Inhibition of Acetolactate Synthase (B/2)
196Rock Bulrush29282
54 August 6, 2024Echinochloa crus-pavonisChinaChina 20249 Auxin Mimics (O/4)
193Gulf Cockspur29283
55 August 3, 2024Amaranthus palmeriUnited States (Oregon) United StatesOregon202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth29270
56 July 21, 2024Chenopodium albumCanada (New Brunswick) CanadaNew Brunswick20187 PSII inhibitors - Serine 264 Binders (C1 C2/5)
47Common Lambsquarters28276
57 July 14, 2024Ambrosia artemisiifoliaCanada (Prince Edward Island) CanadaPrince Edward Island20237 PSII inhibitors - Serine 264 Binders (C1 C2/5)
18Common Ragweed28275
58 July 12, 2024Amaranthus retroflexusCanada (Prince Edward Island) CanadaPrince Edward Island20237 PSII inhibitors - Serine 264 Binders (C1 C2/5)
16Redroot Pigweed28274
59 July 8, 2024Chenopodium albumCanada (Prince Edward Island) CanadaPrince Edward Island20187 PSII inhibitors - Serine 264 Binders (C1 C2/5)
47Common Lambsquarters28273
60 June 15, 2024Oryza sativa var. sylvaticaArgentinaArgentina 201848 Inhibition of Acetolactate Synthase (B/2)
242Red Rice27289
61 June 8, 2024Conyza bonariensisUruguayUruguay 202273 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
60Hairy Fleabane27291
62 June 6, 2024Cyperus difformisPortugalPortugal 202334 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Histidine 215 Binders (C3/6)
71Smallflower Umbrella Sedge28270
63 May 24, 2024Bidens pilosaBrazilBrazil 20225 Inhibition of Protoporphyrinogen Oxidase (E/14)
32Hairy Beggarticks27288
64 May 24, 2024Digitaria sanguinalisSwitzerlandSwitzerland 202141 Inhibition of Acetolactate Synthase (B/2)
77Large Crabgrass27290
65 May 24, 2024Amaranthus hybridus (syn: quitensis)South AfricaSouth Africa 202437 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
12Smooth Pigweed27287
66 May 19, 2024Glebionis segetumGreeceGreece 202119 Inhibition of Acetolactate Synthase (B/2)
2358Corn Marigold28272
67 May 4, 2024Echinochloa phyllopogon (=E. oryzicola)PortugalPortugal 202034 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
178Late Watergrass28269
68 April 20, 2024Echinochloa phyllopogon (=E. oryzicola)PortugalPortugal 202034 Inhibition of Acetyl CoA Carboxylase (A/1)
178Late Watergrass28268
69 April 9, 2024Papaver rhoeasPortugalPortugal 201834 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Auxin Mimics (O/4)
123Corn Poppy28267
70 March 25, 2024Chloris truncataSpainSpain 202338 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
262Windmill Grass27293
71 March 18, 2024Conyza canadensisUnited States (Oregon) United StatesOregon202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
61Horseweed27286
72 March 18, 2024Conyza bonariensisUnited States (Oregon) United StatesOregon202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
60Hairy Fleabane27285
73 March 18, 2024Amaranthus palmeriUnited States (Iowa) United StatesIowa202245 Multiple Resistance: 4 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth27284
74 March 5, 2024Papaver rhoeasPortugalPortugal 201834 Inhibition of Acetolactate Synthase (B/2)
123Corn Poppy28271
75 March 3, 2024Lolium perenne ssp. multiflorumPortugalPortugal 201934 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
110Italian Ryegrass28266
76 February 24, 2024Echinochloa crus-galli var. crus-galliPortugalPortugal 201834 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
79Barnyardgrass28265
77 February 20, 2024Amaranthus palmeriSpainSpain 202338 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth27292
78 January 21, 2024Bromus diandrusNew ZealandNew Zealand 202430 Inhibition of Acetolactate Synthase (B/2)
197Ripgut Brome27283
79 November 19, 2023Avena sterilisSpainSpain 202338 Inhibition of Acetyl CoA Carboxylase (A/1)
29Sterile Oat27282
80 November 9, 2023Amaranthus tuberculatus (=A. rudis)United States (Idaho) United StatesIdaho202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
219Tall Waterhemp27264
81 November 3, 2023Amaranthus hybridus (syn: quitensis)ItalyItaly 201824 Inhibition of Acetolactate Synthase (B/2)
12Smooth Pigweed27281
82 October 30, 2023Amaranthus tuberculatus (=A. rudis)United States (Iowa) United StatesIowa202145 Auxin Mimics (O/4)
219Tall Waterhemp27263
83 October 26, 2023Conyza bonariensisJordanJordan 202255 Multiple Resistance: 2 Sites of Action
PS I Electron Diversion (D/22)
Inhibition of Protoporphyrinogen Oxidase (E/14)
60Hairy Fleabane27269
84 October 25, 2023Echinochloa crus-galli var. crus-galliThailandThailand 202147 Inhibition of Cellulose Synthesis (L/26)
79Barnyardgrass27275
85 October 18, 2023Poa annuaIrelandIreland 202181 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
130Annual Bluegrass27262
86 September 26, 2023Monochoria vaginalisIndonesiaIndonesia 202222 Inhibition of Acetolactate Synthase (B/2)
202Arrowleafed Monochoria27274
87 September 14, 2023Ambrosia artemisiifoliaUkraineUkraine 2023230 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Protoporphyrinogen Oxidase (E/14)
18Common Ragweed26266
88 September 5, 2023Echinochloa crus-galli var. crus-galliBrazilBrazil 20185 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Cellulose Synthesis (L/26)
Auxin Mimics (O/4)
79Barnyardgrass26265
89 September 5, 2023Bidens subalternansBrazilBrazil 20235 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
194Greater Beggarticks26263
90 September 5, 2023Sagittaria montevidensisBrazilBrazil 20235 Auxin Mimics (O/4)
146California Arrowhead26264
91 August 28, 2023Bromus diandrusAustralia (Western Australia) AustraliaWestern Australia20201 Inhibition of Acetyl CoA Carboxylase (A/1)
197Ripgut Brome26262
92 August 5, 2023Panicum miliaceum var. ruderale Kitag.ChinaChina 20239 Inhibition of Acetolactate Synthase (B/2)
1359Wild Panicgrass27273
93 July 13, 2023Echinochloa crus-galli var. crus-galliIndiaIndia 201721 Inhibition of Acetolactate Synthase (B/2)
79Barnyardgrass25264
94 July 11, 2023Amaranthus palmeriUnited States (Colorado) United StatesColorado202145 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth25265
95 July 6, 2023Digitaria sanguinalisNew ZealandNew Zealand 202230 Inhibition of Acetolactate Synthase (B/2)
77Large Crabgrass25262
96 June 29, 2023Hordeum jubatumCanada (Alberta) CanadaAlberta20227 Inhibition of Acetyl CoA Carboxylase (A/1)
358Foxtail Barley25263
97 June 23, 2023Ammannia multifloraChinaChina 20229 Inhibition of Acetolactate Synthase (B/2)
1360Many Flowered Ammannia27279
98 June 8, 2023Galium spuriumGreeceGreece 202219 Inhibition of Acetolactate Synthase (B/2)
93False Cleavers27278
99 June 5, 2023Plantago lanceolataSouth AfricaSouth Africa 202237 Multiple Resistance: 2 Sites of Action
PS I Electron Diversion (D/22)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
220Buckhorn Plantain27276
100 June 3, 2023Ambrosia artemisiifoliaUnited States (Michigan) United StatesMichigan202245 Auxin Mimics (O/4)
18Common Ragweed27277
101 May 9, 2023Echinochloa oryzoidesArgentinaArgentina 201648 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
261Early Watergrass25261
102 May 9, 2023Poa annuaUnited States (Georgia) United StatesGeorgia202245 Inhibition of Cellulose Synthesis (L/29)
130Annual Bluegrass25260
103 April 25, 2023Kochia scopariaCanada (Saskatchewan) CanadaSaskatchewan20217 Inhibition of Protoporphyrinogen Oxidase (E/14)
101Kochia25259
104 April 24, 2023Bromus commutatusUnited KingdomUnited Kingdom 202044 Inhibition of Acetolactate Synthase (B/2)
357Meadow Brome25258
105 April 23, 2023Bromus sterilisUnited KingdomUnited Kingdom 202044 Inhibition of Acetolactate Synthase (B/2)
289Poverty Brome25257
106 April 23, 2023Bromus diandrusUnited KingdomUnited Kingdom 202044 Inhibition of Acetolactate Synthase (B/2)
197Ripgut Brome25256
107 April 4, 2023Lolium perenne ssp. multiflorumChinaChina 20229 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
110Italian Ryegrass27266
108 March 30, 2023Digitaria ciliarisChinaChina 20219 Inhibition of Acetyl CoA Carboxylase (A/1)
225Southern Crabgrass27272
109 March 15, 2023Amaranthus retroflexusUnited States (North Carolina) United StatesNorth Carolina202245 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
16Redroot Pigweed24259
110 March 15, 2023Amaranthus retroflexusUnited States (North Carolina) United StatesNorth Carolina202245 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
16Redroot Pigweed24258
111 March 12, 2023Echinochloa phyllopogon (=E. oryzicola)ChinaChina 20239 Inhibition of Acetolactate Synthase (B/2)
178Late Watergrass27267
112 March 11, 2023Ammannia auriculataChinaChina 20239 Inhibition of Acetolactate Synthase (B/2)
183Eared Redstem27280
113 March 8, 2023Cyperus esculentusItalyItaly 201724 Inhibition of Acetolactate Synthase (B/2)
290Yellow Nutsedge24256
114 February 16, 2023Stellaria mediaUnited States (California) United StatesCalifornia202245 Inhibition of Acetolactate Synthase (B/2)
168Common Chickweed24253
115 February 2, 2023Leptochloa chinensisChinaChina 20239 Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
223Chinese Sprangletop27268
116 January 31, 2023Amaranthus palmeriUruguayUruguay 202273 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth24254
117 January 31, 2023Amaranthus hybridus (syn: quitensis)UruguayUruguay 202273 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
12Smooth Pigweed24255
118 December 20, 2022Lolium perenne ssp. multiflorumUnited States (North Carolina) United StatesNorth Carolina202245 Multiple Resistance: 4 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
PS I Electron Diversion (D/22)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
110Italian Ryegrass24251
119 December 4, 2022Amaranthus hybridus (syn: quitensis)ParaguayParaguay 202246 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
12Smooth Pigweed24252
120 November 22, 2022Chenopodium albumUkraineUkraine 2022230 Inhibition of Acetolactate Synthase (B/2)
47Common Lambsquarters24250
121 November 3, 2022Lolium perenne ssp. multiflorumSwitzerlandSwitzerland 202041 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
110Italian Ryegrass24249
122 November 3, 2022Conyza canadensisSwitzerlandSwitzerland 202141 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
61Horseweed24248
123 April 9, 2022Amaranthus palmeriUnited States (Idaho) United StatesIdaho202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
14Palmer Amaranth27265
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