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 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
2 November 28, 2019Amaranthus palmeriUnited States (North Carolina) United StatesNorth Carolina201645 HPPD inhibitors (F2/27)
14Palmer Amaranth18188
3 November 28, 2019Secale cerealeUnited States (Colorado) United StatesColorado201845 ALS inhibitors (B/2)
351Feral Rye18182
4 November 28, 2019Echinochloa crus-galli var. crus-galliArgentinaArgentina 201948 EPSP synthase inhibitors (G/9)
79Barnyardgrass18183
5 November 22, 2019Avena sterilis ssp. ludovicianaAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
30Sterile oat18187
6 November 22, 2019Avena sterilis ssp. ludovicianaAustralia (New South Wales ) AustraliaNew South Wales 20181 EPSP synthase inhibitors (G/9)
30Sterile oat18186
7 November 22, 2019Sonchus asperUnited KingdomUnited Kingdom 201644 ALS inhibitors (B/2)
163Spiny Sowthistle18185
8 November 19, 2019Rumex obtusifoliusFranceFrance 201717 ALS inhibitors (B/2)
349Broad-Leaved Dock18178
9 November 4, 2019Eleusine indicaColombiaColombia 201610 Multiple Resistance: 2 Sites of Action
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
81Goosegrass18177
10 October 24, 2019Capsella bursa-pastorisNorwayNorway 201931 ALS inhibitors (B/2)
41Shepherd's-purse18169
11 October 1, 2019Carduus acanthoidesArgentinaArgentina 201948 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
348Plumeless Thistle18173
12 September 28, 2019Echinochloa colonaColombiaColombia 201610 Multiple Resistance: 3 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
Cellulose inhibitors (L/26)
78Junglerice18163
13 September 25, 2019Urochloa panicoidesArgentinaArgentina 201748 EPSP synthase inhibitors (G/9)
171Liverseedgrass18158
14 September 24, 2019Oryza sativa var. sylvaticaColombiaColombia 201810 ALS inhibitors (B/2)
242Red Rice18170
15 September 2, 2019Rapistrum rugosumSpainSpain 201838 ALS inhibitors (B/2)
142Turnipweed18171
16 August 19, 2019Conyza sumatrensisTurkeyTurkey 201971 EPSP synthase inhibitors (G/9)
65Sumatran Fleabane18164
17 August 5, 2019Lithospermum arvenseChinaChina 20199 ALS inhibitors (B/2)
341Corn Gromwell18168
18 July 31, 2019Lolium perenne ssp. multiflorumUnited States (Oklahoma) United StatesOklahoma201745 ACCase inhibitors (A/1)
110Italian Ryegrass18167
19 July 31, 2019Chloris radiataColombiaColombia 201910 EPSP synthase inhibitors (G/9)
340Radiate Fingergrass18165
20 June 25, 2019Amaranthus palmeriUnited States (Arkansas) United StatesArkansas201645 Multiple Resistance: 5 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
Microtubule inhibitors (K1/3)
Long chain fatty acid inhibitors (K3/15)
14Palmer Amaranth18156
21 June 25, 2019Conyza sumatrensisParaguayParaguay 201746 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
65Sumatran Fleabane18153
22 May 15, 2019Amaranthus tuberculatus (=A. rudis)Canada (Ontario) CanadaOntario20177 Multiple Resistance: 2 Sites of Action
Photosystem II inhibitors (C1/5)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp17142
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 April 2, 2019Sorghum halepenseIsraelIsrael 201723 ALS inhibitors (B/2)
166Johnsongrass18159
26 March 1, 2019Amaranthus palmeriUnited States (Arkansas) United StatesArkansas201745 Long chain fatty acid inhibitors (K3/15)
14Palmer Amaranth18154
27 February 9, 2019Amaranthus tuberculatus (=A. rudis)United States (Illinois) United StatesIllinois201645 Long chain fatty acid inhibitors (K3/15)
219Tall Waterhemp18152
28 January 9, 2019Amaranthus palmeriUnited States (Kansas) United StatesKansas201845 Synthetic Auxins (O/4)
14Palmer Amaranth18151
29 December 31, 2018Ambrosia artemisiifoliaUnited States (Wisconsin) United StatesWisconsin201745 EPSP synthase inhibitors (G/9)
18Common Ragweed17155
30 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Washington) United StatesWashington201845 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17154
31 December 15, 2018Lolium perenne ssp. multiflorumUnited KingdomUnited Kingdom 201844 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17153
32 December 15, 2018Lolium perenne ssp. multiflorumFranceFrance 201817 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17152
33 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Oregon) United StatesOregon201845 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17151
34 November 9, 2018Bidens subalternansParaguayParaguay 201846 EPSP synthase inhibitors (G/9)
194Greater Beggarticks17150
35 October 10, 2018Conyza canadensisUnited States (Oklahoma) United StatesOklahoma201845 ALS inhibitors (B/2)
61Horseweed17149
36 October 2, 2018Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 PSI Electron Diverter (D/22)
65Sumatran Fleabane17148
37 September 25, 2018Kochia scopariaCanada (Alberta) CanadaAlberta20177 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
101Kochia17147
38 August 27, 2018Galium aparineIranIran 201779 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
272Catchweed Bedstraw17138
39 August 16, 2018Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 201648 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
12Smooth Pigweed17107
40 July 17, 2018Sorghum halepenseSerbiaSerbia 2017245 ACCase inhibitors (A/1)
166Johnsongrass17146
41 July 16, 2018Oryza sativa var. sylvaticaMalaysiaMalaysia 201828 ALS inhibitors (B/2)
242Red Rice17145
42 July 2, 2018Bromus catharticusArgentinaArgentina 201748 EPSP synthase inhibitors (G/9)
338Rescuegrass17144
43 June 26, 2018Bromus sterilisGermanyGermany 201718 ALS inhibitors (B/2)
289Poverty Brome17143
44 June 7, 2018Amaranthus tuberculatus (=A. rudis)Canada (Ontario) CanadaOntario20177 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp17141
45 June 7, 2018Amaranthus tuberculatus (=A. rudis)Canada (Ontario) CanadaOntario20177 Multiple Resistance: 4 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp17140
46 April 25, 2018Lolium rigidumGreeceGreece 201719 Glutamine synthase inhibitors (H/10)
112Rigid Ryegrass17136
47 April 25, 2018Lolium rigidumGreeceGreece 201619 EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17137
48 April 13, 2018Conyza sumatrensisBrazilBrazil 20175 Multiple Resistance: 5 Sites of Action
PSII inhibitor (Ureas and amides) (C2/7)
PSI Electron Diverter (D/22)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
65Sumatran Fleabane17135
49 April 2, 2018Amaranthus palmeriUnited States (Oklahoma) United StatesOklahoma201845 EPSP synthase inhibitors (G/9)
14Palmer Amaranth17134
50 March 8, 2018Plantago lanceolataUnited States (Indiana) United StatesIndiana201645 Synthetic Auxins (O/4)
220Buckhorn Plantain17133
51 February 5, 2018Amaranthus tuberculatus (=A. rudis)United States (Nebraska) United StatesNebraska201645 Multiple Resistance: 4 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp17121
52 January 28, 2018Brassica rapa (=B. campestris)Canada (Quebec) CanadaQuebec20177 EPSP synthase inhibitors (G/9)
36Birdsrape Mustard17130
53 December 30, 2017Hordeum murinum ssp. glaucumAustralia (South Australia) AustraliaSouth Australia20161 EPSP synthase inhibitors (G/9)
97Smooth Barley17118
54 December 8, 2017Eleusine indicaBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
EPSP synthase inhibitors (G/9)
81Goosegrass17112
55 December 5, 2017Conyza sumatrensisFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
65Sumatran Fleabane17115
56 December 5, 2017Conyza sumatrensisFranceFrance 201617 ALS inhibitors (B/2)
65Sumatran Fleabane17114
57 December 5, 2017Echinochloa crus-galli var. crus-galliUkraineUkraine 2017230 ALS inhibitors (B/2)
79Barnyardgrass17113
58 November 27, 2017Lactuca salignaAustralia (Western Australia) AustraliaWestern Australia20171 EPSP synthase inhibitors (G/9)
336Willow-leaved lettuce17111
59 November 9, 2017Ambrosia artemisiifoliaUnited States (New Jersey) United StatesNew Jersey201645 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
18Common Ragweed17110
60 November 9, 2017Ambrosia artemisiifoliaUnited States (Maryland) United StatesMaryland201645 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
18Common Ragweed17109
61 October 12, 2017Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 201648 Synthetic Auxins (O/4)
12Smooth Pigweed17108
62 October 5, 2017Ambrosia artemisiifoliaUnited States (Michigan) United StatesMichigan201645 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
18Common Ragweed17106
63 September 27, 2017Lolium rigidumSpainSpain 201638 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17105
64 September 27, 2017Lolium perenne ssp. multiflorumUnited States (California) United StatesCalifornia201645 Multiple Resistance: 4 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
110Italian Ryegrass17104
65 September 19, 2017Conyza sumatrensisBrazilBrazil 20175 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
65Sumatran Fleabane17102
66 September 14, 2017Hirschfeldia incanaArgentinaArgentina 201648 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
328Shortpod Mustard17103
67 August 6, 2017Conyza sumatrensisBrazilBrazil 20175 PPO inhibitors (E/14)
65Sumatran Fleabane17099
68 July 28, 2017Amaranthus tuberculatus (=A. rudis)United States (Wisconsin) United StatesWisconsin201645 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp16100
69 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Multiple Resistance: 5 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
EPSP synthase inhibitors (G/9)
Microtubule inhibitors (K1/3)
Unknown (Z/27)
130Annual Bluegrass16098
70 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16097
71 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Unknown (Z/27)
130Annual Bluegrass16096
72 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16095
73 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16094
74 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 ALS inhibitors (B/2)
130Annual Bluegrass16093
75 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16092
76 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16091
77 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16090
78 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 ALS inhibitors (B/2)
130Annual Bluegrass16089
79 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 ALS inhibitors (B/2)
130Annual Bluegrass16088
80 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16087
81 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Unknown (Z/27)
130Annual Bluegrass16086
82 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16085
83 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16084
84 June 28, 2017Conyza sumatrensisBrazilBrazil 20165 PSI Electron Diverter (D/22)
65Sumatran Fleabane16082
85 June 28, 2017Galium aparineIranIran 201679 Synthetic Auxins (O/4)
272Catchweed Bedstraw16083
86 May 16, 2017Amaranthus retroflexusChinaChina 20179 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
16Redroot Pigweed16078
87 May 12, 2017Conyza canadensisSouth KoreaSouth Korea 201727 EPSP synthase inhibitors (G/9)
61Horseweed16077
88 May 7, 2017Apera spica-ventiDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
20Silky Windgrass15078
89 May 7, 2017Lolium perenneDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
111Perennial Ryegrass15077
90 March 21, 2017Bromus tectorumUnited States (Montana) United StatesMontana201645 ALS inhibitors (B/2)
40Downy Brome (Cheatgrass)15071
91 March 20, 2017Conyza canadensisHungaryHungary 201620 EPSP synthase inhibitors (G/9)
61Horseweed15070
92 March 8, 2017Stellaria mediaLatviaLatvia 2016174 ALS inhibitors (B/2)
168Common Chickweed15068
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Cite this site as: Heap, I.  The International Survey of Herbicide Resistant Weeds.  Online.  Internet.  Saturday, December 14, 2019 .  Available  www.weedscience.org
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