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 13, 2018Lolium rigidumGreeceGreece 201619 EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17137
2 April 13, 2018Lolium rigidumGreeceGreece 201719 Glutamine synthase inhibitors (H/10)
112Rigid Ryegrass17136
3 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
4 April 2, 2018Amaranthus palmeriUnited States (Oklahoma) United StatesOklahoma201845 EPSP synthase inhibitors (G/9)
14Palmer Amaranth17134
5 March 8, 2018Plantago lanceolataUnited States (Indiana) United StatesIndiana201645 Synthetic Auxins (O/4)
220Buckhorn Plantain17133
6 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
7 January 28, 2018Brassica rapa (=B. campestris)Canada (Quebec) CanadaQuebec20177 EPSP synthase inhibitors (G/9)
36Birdsrape Mustard17130
8 January 27, 2018Sorghum halepenseHungaryHungary 201720 ALS inhibitors (B/2)
166Johnsongrass17119
9 December 30, 2017Hordeum murinum ssp. glaucumAustralia (South Australia) AustraliaSouth Australia20161 EPSP synthase inhibitors (G/9)
97Smooth Barley17118
10 December 8, 2017Eleusine indicaBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
EPSP synthase inhibitors (G/9)
81Goosegrass17112
11 December 5, 2017Conyza sumatrensisFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
65Sumatran Fleabane17115
12 December 5, 2017Conyza sumatrensisFranceFrance 201617 ALS inhibitors (B/2)
65Sumatran Fleabane17114
13 December 5, 2017Echinochloa crus-galli var. crus-galliUkraineUkraine 2017230 ALS inhibitors (B/2)
79Barnyardgrass17113
14 November 27, 2017Lactuca salignaAustralia (Western Australia) AustraliaWestern Australia20171 EPSP synthase inhibitors (G/9)
336Willow-leaved lettuce17111
15 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
16 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
17 October 12, 2017Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 201648 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
12Smooth Pigweed17107
18 October 12, 2017Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 201648 Synthetic Auxins (O/4)
12Smooth Pigweed17108
19 October 5, 2017Ambrosia artemisiifoliaUnited States (Michigan) United StatesMichigan201645 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
18Common Ragweed17106
20 September 27, 2017Lolium rigidumSpainSpain 201638 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17105
21 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
22 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
23 September 14, 2017Hirschfeldia incanaArgentinaArgentina 201648 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
328Shortpod Mustard17103
24 August 6, 2017Conyza sumatrensisBrazilBrazil 20175 PPO inhibitors (E/14)
65Sumatran Fleabane17099
25 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
26 July 28, 2017Galium aparineIranIran 201779 ALS inhibitors (B/2)
272Catchweed Bedstraw15064
27 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
28 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16097
29 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Unknown (Z/27)
130Annual Bluegrass16096
30 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16095
31 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16094
32 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 ALS inhibitors (B/2)
130Annual Bluegrass16093
33 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16092
34 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16091
35 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16090
36 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 ALS inhibitors (B/2)
130Annual Bluegrass16089
37 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 ALS inhibitors (B/2)
130Annual Bluegrass16088
38 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16087
39 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Unknown (Z/27)
130Annual Bluegrass16086
40 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16085
41 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16084
42 June 28, 2017Conyza sumatrensisBrazilBrazil 20165 PSI Electron Diverter (D/22)
65Sumatran Fleabane16082
43 June 28, 2017Galium aparineIranIran 201679 Synthetic Auxins (O/4)
272Catchweed Bedstraw16083
44 June 6, 2017Lolium perenne ssp. multiflorumBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
110Italian Ryegrass15063
45 May 16, 2017Amaranthus retroflexusChinaChina 20179 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
16Redroot Pigweed16078
46 May 12, 2017Conyza canadensisSouth KoreaSouth Korea 201727 EPSP synthase inhibitors (G/9)
61Horseweed16077
47 May 7, 2017Apera spica-ventiDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
20Silky Windgrass15078
48 May 7, 2017Lolium perenneDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
111Perennial Ryegrass15077
49 March 21, 2017Bromus tectorumUnited States (Montana) United StatesMontana201645 ALS inhibitors (B/2)
40Downy Brome (Cheatgrass)15071
50 March 20, 2017Conyza canadensisHungaryHungary 201620 EPSP synthase inhibitors (G/9)
61Horseweed15070
51 March 8, 2017Stellaria mediaLatviaLatvia 2016174 ALS inhibitors (B/2)
168Common Chickweed15068
52 December 12, 2016Lolium perenne ssp. multiflorumBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
110Italian Ryegrass15057
53 November 27, 2016Papaver rhoeasFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
123Corn Poppy15054
54 November 2, 2016Bidens pilosaBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
32Hairy Beggarticks14053
55 October 27, 2016Tridax procumbensAustralia (Western Australia) AustraliaWestern Australia20161 EPSP synthase inhibitors (G/9)
333Coat Buttons14052
56 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
57 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
58 October 23, 2016Salsola tragusUnited States (Oregon) United StatesOregon201645 EPSP synthase inhibitors (G/9)
147Russian-thistle13055
59 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
60 September 2, 2016Amaranthus palmeriUnited States (Nebraska) United StatesNebraska201645 Multiple Resistance: 2 Sites of Action
Photosystem II inhibitors (C1/5)
EPSP synthase inhibitors (G/9)
14Palmer Amaranth13047
61 August 19, 2016Conyza bonariensisAustralia (New South Wales ) AustraliaNew South Wales 20161 PSI Electron Diverter (D/22)
60Hairy Fleabane13045
62 July 19, 2016Digitaria insularisBrazilBrazil 20165 ACCase inhibitors (A/1)
239Sourgrass13043
63 July 19, 2016Amaranthus palmeriBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
14Palmer Amaranth13042
64 June 28, 2016Eleusine indicaBrazilBrazil 20165 EPSP synthase inhibitors (G/9)
81Goosegrass13039
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Cite this site as: Heap, I.  The International Survey of Herbicide Resistant Weeds.  Online.  Internet.  Thursday, April 19, 2018 .  Available  www.weedscience.org
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