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