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 April 2, 2019Sorghum halepenseIsraelIsrael 201723 ALS inhibitors (B/2)
166Johnsongrass18159
2 March 30, 2019Urochloa panicoidesArgentinaArgentina 201748 EPSP synthase inhibitors (G/9)
171Liverseedgrass18158
3 March 12, 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
4 March 1, 2019Amaranthus palmeriUnited States (Arkansas) United StatesArkansas201745 Long chain fatty acid inhibitors (K3/15)
14Palmer Amaranth18154
5 February 9, 2019Amaranthus tuberculatus (=A. rudis)United States (Illinois) United StatesIllinois201645 Long chain fatty acid inhibitors (K3/15)
219Tall Waterhemp18152
6 February 6, 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
7 January 9, 2019Amaranthus palmeriUnited States (Kansas) United StatesKansas201845 Synthetic Auxins (O/4)
14Palmer Amaranth18151
8 December 31, 2018Ambrosia artemisiifoliaUnited States (Wisconsin) United StatesWisconsin201745 EPSP synthase inhibitors (G/9)
18Common Ragweed17155
9 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Washington) United StatesWashington201845 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17154
10 December 15, 2018Lolium perenne ssp. multiflorumUnited KingdomUnited Kingdom 201844 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17153
11 December 15, 2018Lolium perenne ssp. multiflorumFranceFrance 201817 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17152
12 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Oregon) United StatesOregon201845 Long chain fatty acid inhibitors (K3/15)
110Italian Ryegrass17151
13 November 9, 2018Bidens subalternansParaguayParaguay 201846 EPSP synthase inhibitors (G/9)
194Greater Beggarticks17150
14 October 10, 2018Conyza canadensisUnited States (Oklahoma) United StatesOklahoma201845 ALS inhibitors (B/2)
61Horseweed17149
15 October 2, 2018Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 PSI Electron Diverter (D/22)
65Sumatran Fleabane17148
16 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
17 August 27, 2018Galium aparineIranIran 201779 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
272Catchweed Bedstraw17138
18 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
19 July 17, 2018Sorghum halepenseSerbiaSerbia 2017245 ACCase inhibitors (A/1)
166Johnsongrass17146
20 July 16, 2018Oryza sativa var. sylvaticaMalaysiaMalaysia 201828 ALS inhibitors (B/2)
242Red Rice17145
21 July 2, 2018Bromus catharticusArgentinaArgentina 201748 EPSP synthase inhibitors (G/9)
338Rescuegrass17144
22 June 26, 2018Bromus sterilisGermanyGermany 201718 ALS inhibitors (B/2)
289Poverty Brome17143
23 June 7, 2018Amaranthus tuberculatus (=A. rudis)Canada (Ontario) CanadaOntario20177 Multiple Resistance: 2 Sites of Action
Photosystem II inhibitors (C1/5)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp17142
24 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
25 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
26 April 25, 2018Lolium rigidumGreeceGreece 201719 Glutamine synthase inhibitors (H/10)
112Rigid Ryegrass17136
27 April 25, 2018Lolium rigidumGreeceGreece 201619 EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17137
28 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
29 April 2, 2018Amaranthus palmeriUnited States (Oklahoma) United StatesOklahoma201845 EPSP synthase inhibitors (G/9)
14Palmer Amaranth17134
30 March 8, 2018Plantago lanceolataUnited States (Indiana) United StatesIndiana201645 Synthetic Auxins (O/4)
220Buckhorn Plantain17133
31 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
32 January 28, 2018Brassica rapa (=B. campestris)Canada (Quebec) CanadaQuebec20177 EPSP synthase inhibitors (G/9)
36Birdsrape Mustard17130
33 January 27, 2018Sorghum halepenseHungaryHungary 201720 ALS inhibitors (B/2)
166Johnsongrass17119
34 December 30, 2017Hordeum murinum ssp. glaucumAustralia (South Australia) AustraliaSouth Australia20161 EPSP synthase inhibitors (G/9)
97Smooth Barley17118
35 December 8, 2017Eleusine indicaBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
EPSP synthase inhibitors (G/9)
81Goosegrass17112
36 December 5, 2017Conyza sumatrensisFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
65Sumatran Fleabane17115
37 December 5, 2017Conyza sumatrensisFranceFrance 201617 ALS inhibitors (B/2)
65Sumatran Fleabane17114
38 December 5, 2017Echinochloa crus-galli var. crus-galliUkraineUkraine 2017230 ALS inhibitors (B/2)
79Barnyardgrass17113
39 November 27, 2017Lactuca salignaAustralia (Western Australia) AustraliaWestern Australia20171 EPSP synthase inhibitors (G/9)
336Willow-leaved lettuce17111
40 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
41 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
42 October 12, 2017Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 201648 Synthetic Auxins (O/4)
12Smooth Pigweed17108
43 October 5, 2017Ambrosia artemisiifoliaUnited States (Michigan) United StatesMichigan201645 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
18Common Ragweed17106
44 September 27, 2017Lolium rigidumSpainSpain 201638 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17105
45 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
46 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
47 September 14, 2017Hirschfeldia incanaArgentinaArgentina 201648 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
328Shortpod Mustard17103
48 August 6, 2017Conyza sumatrensisBrazilBrazil 20175 PPO inhibitors (E/14)
65Sumatran Fleabane17099
49 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
50 July 28, 2017Galium aparineIranIran 201779 ALS inhibitors (B/2)
272Catchweed Bedstraw15064
51 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
52 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16097
53 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Unknown (Z/27)
130Annual Bluegrass16096
54 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16095
55 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16094
56 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 ALS inhibitors (B/2)
130Annual Bluegrass16093
57 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16092
58 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16091
59 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16090
60 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 ALS inhibitors (B/2)
130Annual Bluegrass16089
61 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 ALS inhibitors (B/2)
130Annual Bluegrass16088
62 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16087
63 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Unknown (Z/27)
130Annual Bluegrass16086
64 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16085
65 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16084
66 June 28, 2017Conyza sumatrensisBrazilBrazil 20165 PSI Electron Diverter (D/22)
65Sumatran Fleabane16082
67 June 28, 2017Galium aparineIranIran 201679 Synthetic Auxins (O/4)
272Catchweed Bedstraw16083
68 June 6, 2017Lolium perenne ssp. multiflorumBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
110Italian Ryegrass15063
69 May 16, 2017Amaranthus retroflexusChinaChina 20179 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
16Redroot Pigweed16078
70 May 12, 2017Conyza canadensisSouth KoreaSouth Korea 201727 EPSP synthase inhibitors (G/9)
61Horseweed16077
71 May 7, 2017Apera spica-ventiDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
20Silky Windgrass15078
72 May 7, 2017Lolium perenneDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
111Perennial Ryegrass15077
73 March 21, 2017Bromus tectorumUnited States (Montana) United StatesMontana201645 ALS inhibitors (B/2)
40Downy Brome (Cheatgrass)15071
74 March 20, 2017Conyza canadensisHungaryHungary 201620 EPSP synthase inhibitors (G/9)
61Horseweed15070
75 March 8, 2017Stellaria mediaLatviaLatvia 2016174 ALS inhibitors (B/2)
168Common Chickweed15068
76 December 12, 2016Lolium perenne ssp. multiflorumBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
110Italian Ryegrass15057
77 November 27, 2016Papaver rhoeasFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
123Corn Poppy15054
78 November 2, 2016Bidens pilosaBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
32Hairy Beggarticks14053
79 October 27, 2016Tridax procumbensAustralia (Western Australia) AustraliaWestern Australia20161 EPSP synthase inhibitors (G/9)
333Coat Buttons14052
80 October 26, 2016Amaranthus tuberculatus (=A. rudis)United States (Illinois) United StatesIllinois201645 Multiple Resistance: 5 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
PPO inhibitors (E/14)
HPPD inhibitors (F2/27)
Synthetic Auxins (O/4)
219Tall Waterhemp14051
81 October 26, 2016Amaranthus tuberculatus (=A. rudis)United States (Minnesota) United StatesMinnesota201645 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
219Tall Waterhemp13056
82 October 23, 2016Salsola tragusUnited States (Oregon) United StatesOregon201645 EPSP synthase inhibitors (G/9)
147Russian-thistle13055
83 September 21, 2016Amaranthus palmeriUnited States (Illinois) United StatesIllinois201645 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
14Palmer Amaranth13050
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