INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
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 March 13, 2021Amaranthus palmeriUnited States (Tennessee) United StatesTennessee202045 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Auxin Mimics (O/4)
 		14Palmer Amaranth19221
2 March 11, 2021Raphanus raphanistrumAustralia (Western Australia) AustraliaWestern Australia20201 Multiple Resistance: 4 Sites of Action
ALS inhibitors (B/2)
HPPD inhibitors (F2/27)
Very Long-Chain Fatty Acid Synthesis inhibitors (K3/15)
Auxin Mimics (O/4)
 		141Wild Radish19219
3 March 10, 2021Salsola tragusArgentinaArgentina 201948 EPSP synthase inhibitors (G/9)
 		147Russian-thistle19218
4 March 9, 2021Oryza sativa var. sylvaticaTurkeyTurkey 202071 ALS inhibitors (B/2)
 		242Red Rice19217
5 February 26, 2021Arctotheca calendulaAustralia (Western Australia) AustraliaWestern Australia20201 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
Phytoene Desaturase inhibitors (F1/12)
EPSP synthase inhibitors (G/9)
 		21Capeweed19216
6 February 23, 2021Rapistrum rugosumAustralia (New South Wales ) AustraliaNew South Wales 20211 ALS inhibitors (B/2)
 		142Turnipweed19215
7 February 23, 2021Echinochloa crus-galli var. crus-galliAustralia (New South Wales ) AustraliaNew South Wales 20211 ACCase inhibitors (A/1)
 		79Barnyardgrass19214
8 February 4, 2021Euphorbia heterophyllaBrazilBrazil 20195 EPSP synthase inhibitors (G/9)
 		87Wild Poinsettia19213
9 February 4, 2021Digitaria insularisBrazilBrazil 20205 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
EPSP synthase inhibitors (G/9)
 		239Sourgrass19212
10 February 1, 2021Echinochloa crus-galli var. crus-galliBrazilBrazil 20205 EPSP synthase inhibitors (G/9)
 		79Barnyardgrass19211
11 December 16, 2020Bromus rubensSpainSpain 201838 EPSP synthase inhibitors (G/9)
 		324Red Brome18210
12 November 26, 2020Bromus madritensisSpainSpain 201838 EPSP synthase inhibitors (G/9)
 		352Compact Brome18209
13 November 13, 2020Eleusine indicaItalyItaly 201924 EPSP synthase inhibitors (G/9)
 		81Goosegrass18208
14 October 20, 2020Amaranthus tuberculatus (=A. rudis)IsraelIsrael 201923 ALS inhibitors (B/2)
 		219Tall Waterhemp18207
15 October 7, 2020Amaranthus palmeriUnited States (Connecticut) United StatesConnecticut201945 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
 		14Palmer Amaranth18206
16 October 1, 2020Apera spica-ventiBelgiumBelgium 20193 ALS inhibitors (B/2)
 		20Silky Windgrass18199
17 September 21, 2020Poa annuaNew ZealandNew Zealand 202030 ACCase inhibitors (A/1)
 		130Annual Bluegrass18203
18 September 10, 2020Avena fatuaIrelandIreland 201981 ACCase inhibitors (A/1)
 		28Wild Oat18200
19 July 3, 2020Conyza canadensisFranceFrance 201917 EPSP synthase inhibitors (G/9)
 		61Horseweed18198
20 June 22, 2020Chloris barbata = (C. inflate)MexicoMexico 201829 EPSP synthase inhibitors (G/9)
 		53Swollen Fingergrass18197
21 June 22, 2020Sorghum halepenseAustralia (Queensland) AustraliaQueensland20191 EPSP synthase inhibitors (G/9)
 		166Johnsongrass18193
22 June 22, 2020Hordeum murinum ssp. leporinumSpainSpain 201838 EPSP synthase inhibitors (G/9)
 		98Hare Barley18192
23 May 20, 2020Eleusine indicaUnited States (Alabama) United StatesAlabama201945 PSI Electron Diverter (D/22)
 		81Goosegrass18191
24 January 22, 2020Avena fatuaAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
 		28Wild Oat18187
25 November 28, 2019Amaranthus hybridus (syn: quitensis)BrazilBrazil 20185 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
 		12Smooth Pigweed18184
26 November 28, 2019Secale cerealeUnited States (Colorado) United StatesColorado201845 ALS inhibitors (B/2)
 		351Feral Rye18182
27 November 28, 2019Echinochloa crus-galli var. crus-galliArgentinaArgentina 201948 EPSP synthase inhibitors (G/9)
 		79Barnyardgrass18183
28 November 22, 2019Avena sterilis ssp. ludovicianaAustralia (New South Wales ) AustraliaNew South Wales 20181 EPSP synthase inhibitors (G/9)
 		30Sterile oat18186
29 October 24, 2019Capsella bursa-pastorisNorwayNorway 201931 ALS inhibitors (B/2)
 		41Shepherd's-purse18169
30 October 1, 2019Carduus acanthoidesArgentinaArgentina 201948 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Auxin Mimics (O/4)
 		348Plumeless Thistle18173
31 September 24, 2019Oryza sativa var. sylvaticaColombiaColombia 201810 ALS inhibitors (B/2)
 		242Red Rice18170
32 September 2, 2019Rapistrum rugosumSpainSpain 201838 ALS inhibitors (B/2)
 		142Turnipweed18171
33 August 19, 2019Conyza sumatrensisTurkeyTurkey 201971 EPSP synthase inhibitors (G/9)
 		65Sumatran Fleabane18164
34 August 5, 2019Lithospermum arvenseChinaChina 20199 ALS inhibitors (B/2)
 		341Corn Gromwell18168
35 July 31, 2019Chloris radiataColombiaColombia 201910 EPSP synthase inhibitors (G/9)
 		340Radiate Fingergrass18165
36 May 13, 2019Galinsoga parvifloraFranceFrance 201817 ALS inhibitors (B/2)
 		339Gallant Soldier18162
37 May 13, 2019Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
 		65Sumatran Fleabane18161
38 January 9, 2019Amaranthus palmeriUnited States (Kansas) United StatesKansas201845 Auxin Mimics (O/4)
 		14Palmer Amaranth18151
39 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Washington) United StatesWashington201845 Very Long-Chain Fatty Acid Synthesis inhibitors (K3/15)
 		110Italian Ryegrass17154
40 December 15, 2018Lolium perenne ssp. multiflorumUnited KingdomUnited Kingdom 201844 Very Long-Chain Fatty Acid Synthesis inhibitors (K3/15)
 		110Italian Ryegrass17153
41 December 15, 2018Lolium perenne ssp. multiflorumFranceFrance 201817 Very Long-Chain Fatty Acid Synthesis inhibitors (K3/15)
 		110Italian Ryegrass17152
42 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Oregon) United StatesOregon201845 Very Long-Chain Fatty Acid Synthesis inhibitors (K3/15)
 		110Italian Ryegrass17151
43 November 9, 2018Bidens subalternansParaguayParaguay 201846 EPSP synthase inhibitors (G/9)
 		194Greater Beggarticks17150
44 October 10, 2018Conyza canadensisUnited States (Oklahoma) United StatesOklahoma201845 ALS inhibitors (B/2)
 		61Horseweed17149
45 October 2, 2018Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 PSI Electron Diverter (D/22)
 		65Sumatran Fleabane17148
46 July 16, 2018Oryza sativa var. sylvaticaMalaysiaMalaysia 201828 ALS inhibitors (B/2)
 		242Red Rice17145
47 April 2, 2018Amaranthus palmeriUnited States (Oklahoma) United StatesOklahoma201845 EPSP synthase inhibitors (G/9)
 		14Palmer Amaranth17134
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