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 October 20, 2020Amaranthus tuberculatus (=A. rudis)IsraelIsrael 201923 ALS inhibitors (B/2)
219Tall Waterhemp18207
2 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
3 October 1, 2020Apera spica-ventiBelgiumBelgium 20193 ALS inhibitors (B/2)
20Silky Windgrass18199
4 September 21, 2020Poa annuaNew ZealandNew Zealand 202030 ACCase inhibitors (A/1)
130Annual Bluegrass18203
5 September 10, 2020Avena fatuaIrelandIreland 201981 ACCase inhibitors (A/1)
28Wild Oat18200
6 July 3, 2020Conyza canadensisFranceFrance 201917 EPSP synthase inhibitors (G/9)
61Horseweed18198
7 June 22, 2020Chloris barbata = (C. inflate)MexicoMexico 201829 EPSP synthase inhibitors (G/9)
53Swollen Fingergrass18197
8 June 22, 2020Sorghum halepenseAustralia (Queensland) AustraliaQueensland20191 EPSP synthase inhibitors (G/9)
166Johnsongrass18193
9 June 22, 2020Hordeum murinum ssp. leporinumSpainSpain 201838 EPSP synthase inhibitors (G/9)
98Hare Barley18192
10 May 20, 2020Eleusine indicaUnited States (Alabama) United StatesAlabama201945 PSI Electron Diverter (D/22)
81Goosegrass18191
11 January 22, 2020Avena fatuaAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
28Wild Oat18187
12 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
13 November 28, 2019Secale cerealeUnited States (Colorado) United StatesColorado201845 ALS inhibitors (B/2)
351Feral Rye18182
14 November 28, 2019Echinochloa crus-galli var. crus-galliArgentinaArgentina 201948 EPSP synthase inhibitors (G/9)
79Barnyardgrass18183
15 November 22, 2019Avena sterilis ssp. ludovicianaAustralia (New South Wales ) AustraliaNew South Wales 20181 EPSP synthase inhibitors (G/9)
30Sterile oat18186
16 October 24, 2019Capsella bursa-pastorisNorwayNorway 201931 ALS inhibitors (B/2)
41Shepherd's-purse18169
17 October 1, 2019Carduus acanthoidesArgentinaArgentina 201948 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
348Plumeless Thistle18173
18 September 24, 2019Oryza sativa var. sylvaticaColombiaColombia 201810 ALS inhibitors (B/2)
242Red Rice18170
19 September 2, 2019Rapistrum rugosumSpainSpain 201838 ALS inhibitors (B/2)
142Turnipweed18171
20 August 19, 2019Conyza sumatrensisTurkeyTurkey 201971 EPSP synthase inhibitors (G/9)
65Sumatran Fleabane18164
21 August 5, 2019Lithospermum arvenseChinaChina 20199 ALS inhibitors (B/2)
341Corn Gromwell18168
22 July 31, 2019Chloris radiataColombiaColombia 201910 EPSP synthase inhibitors (G/9)
340Radiate Fingergrass18165
23 May 13, 2019Galinsoga parvifloraFranceFrance 201817 ALS inhibitors (B/2)
339Gallant Soldier18162
24 May 13, 2019Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
65Sumatran Fleabane18161
25 January 9, 2019Amaranthus palmeriUnited States (Kansas) United StatesKansas201845 Synthetic Auxins (O/4)
14Palmer Amaranth18151
26 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Washington) United StatesWashington201845 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17154
27 December 15, 2018Lolium perenne ssp. multiflorumUnited KingdomUnited Kingdom 201844 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17153
28 December 15, 2018Lolium perenne ssp. multiflorumFranceFrance 201817 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17152
29 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Oregon) United StatesOregon201845 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17151
30 November 9, 2018Bidens subalternansParaguayParaguay 201846 EPSP synthase inhibitors (G/9)
194Greater Beggarticks17150
31 October 10, 2018Conyza canadensisUnited States (Oklahoma) United StatesOklahoma201845 ALS inhibitors (B/2)
61Horseweed17149
32 October 2, 2018Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 PSI Electron Diverter (D/22)
65Sumatran Fleabane17148
33 July 16, 2018Oryza sativa var. sylvaticaMalaysiaMalaysia 201828 ALS inhibitors (B/2)
242Red Rice17145
34 April 2, 2018Amaranthus palmeriUnited States (Oklahoma) United StatesOklahoma201845 EPSP synthase inhibitors (G/9)
14Palmer Amaranth17134


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Heap, I.  The International Herbicide-Resistant Weed Database.  Online.  Tuesday, October 20, 2020 .  Available  www.weedscience.org Copyright © 1993- 2020 WeedScience.org All rights reserved. Fair use of this material is encouraged. Proper citation is requested.