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 August 6, 2017Conyza sumatrensisBrazilBrazil 20175 PPO inhibitors (E/14)
65Sumatran Fleabane17099
2 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
3 July 28, 2017Amaranthus palmeriUnited States (Wisconsin) United StatesWisconsin201445 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
HPPD inhibitors (F2/27)
14Palmer Amaranth16099
4 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
5 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16097
6 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Unknown (Z/27)
130Annual Bluegrass16096
7 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16095
8 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16094
9 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 ALS inhibitors (B/2)
130Annual Bluegrass16093
10 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16092
11 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16091
12 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16090
13 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 ALS inhibitors (B/2)
130Annual Bluegrass16089
14 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 ALS inhibitors (B/2)
130Annual Bluegrass16088
15 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16087
16 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Unknown (Z/27)
130Annual Bluegrass16086
17 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16085
18 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16084
19 June 28, 2017Galium aparineIranIran 201679 Synthetic Auxins (O/4)
272Catchweed Bedstraw16083
20 June 28, 2017Conyza sumatrensisBrazilBrazil 20165 PSI Electron Diverter (D/22)
65Sumatran Fleabane16082
21 June 28, 2017Amaranthus spinosusUnited States (Mississippi) United StatesMississippi201345 ALS inhibitors (B/2)
278Spiny Amaranth16081
22 June 16, 2017Amaranthus tuberculatus (=A. rudis)United States (Mississippi) United StatesMississippi201045 ALS inhibitors (B/2)
219Tall Waterhemp16080
23 June 16, 2017Amaranthus retroflexusUnited States (Mississippi) United StatesMississippi201045 ALS inhibitors (B/2)
16Redroot Pigweed16079
24 May 16, 2017Amaranthus retroflexusChinaChina 20179 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
16Redroot Pigweed16078
25 May 12, 2017Conyza canadensisSouth KoreaSouth Korea 201727 EPSP synthase inhibitors (G/9)
61Horseweed16077
26 May 7, 2017Apera spica-ventiDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
20Silky Windgrass15078
27 May 7, 2017Lolium perenneDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
111Perennial Ryegrass15077
28 April 11, 2017Tripleurospermum perforatum (=T. inodorum)SwedenSweden 201540 ALS inhibitors (B/2)
116Scentless Chamomile15076
29 April 11, 2017Matricaria recutita (= M. chamomilla)SwedenSweden 201440 ALS inhibitors (B/2)
248Wild Chamomile15075
30 April 11, 2017Phalaris minorPakistanPakistan 201586 ACCase inhibitors (A/1)
127Little seed Canary grass15074
31 April 3, 2017Eleusine indicaUnited States (Virginia) United StatesVirginia201545 PPO inhibitors (E/14)
81Goosegrass15073
32 April 3, 2017Eleusine indicaUnited States (North Carolina) United StatesNorth Carolina201545 PPO inhibitors (E/14)
81Goosegrass15072
33 March 21, 2017Bromus tectorumUnited States (Montana) United StatesMontana201645 ALS inhibitors (B/2)
40Downy Brome (Cheatgrass)15071
34 March 20, 2017Conyza canadensisHungaryHungary 201620 EPSP synthase inhibitors (G/9)
61Horseweed15070
35 March 8, 2017Echinochloa crus-galli var. crus-galliBrazilBrazil 20155 Multiple Resistance: 3 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
Cellulose inhibitors (L/26)
79Barnyardgrass15069
36 March 8, 2017Stellaria mediaLatviaLatvia 2016174 ALS inhibitors (B/2)
168Common Chickweed15068
37 March 8, 2017Apera spica-ventiLatviaLatvia 2015174 ALS inhibitors (B/2)
20Silky Windgrass15067
38 February 22, 2017Lolium perenne ssp. multiflorumUnited States (California) United StatesCalifornia201545 Multiple Resistance: 3 Sites of Action
ACCase inhibitors (A/1)
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
110Italian Ryegrass15066
39 February 22, 2017Sorghum halepenseSerbiaSerbia 2014245 ALS inhibitors (B/2)
166Johnsongrass15065
40 July 28, 2017Galium aparineIranIran 201779 ALS inhibitors (B/2)
272Catchweed Bedstraw15064
41 June 6, 2017Lolium perenne ssp. multiflorumBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
110Italian Ryegrass15063
42 February 9, 2017Helianthus annuusUnited States (Texas) United StatesTexas201545 EPSP synthase inhibitors (G/9)
95Common Sunflower15062
43 December 16, 2016Centaurea stoebe ssp. micranthosCanada (British Columbia) CanadaBritish Columbia20137 Synthetic Auxins (O/4)
334Spotted knapweed15061
44 December 18, 2016Avena fatuaSyriaSyria 201569 ACCase inhibitors (A/1)
28Wild Oat15060
45 December 18, 2016Phalaris paradoxaSyriaSyria 201569 ACCase inhibitors (A/1)
128Hood Canarygrass15059
46 December 18, 2016Phalaris brachystachysSyriaSyria 201569 ACCase inhibitors (A/1)
244Shortspike Canarygrass15058
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 December 2, 2016Sonchus oleraceusAustralia (Victoria) AustraliaVictoria20151 Synthetic Auxins (O/4)
164Annual Sowthistle15056
49 December 2, 2016Arctotheca calendulaAustralia (South Australia) AustraliaSouth Australia20151 Synthetic Auxins (O/4)
21Capeweed15055
50 November 27, 2016Papaver rhoeasFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
123Corn Poppy15054
51 November 21, 2016Sonchus asperFranceFrance 201517 ALS inhibitors (B/2)
163Spiny Sowthistle14058
52 November 17, 2016Ranunculus acrisNew ZealandNew Zealand 201030 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
140Tall Buttercup14057
53 November 17, 2016Lolium perenne ssp. multiflorumNew ZealandNew Zealand 201530 Multiple Resistance: 3 Sites of Action
Carotenoid biosynthesis (unknown target) (F3/11)
EPSP synthase inhibitors (G/9)
Glutamine synthase inhibitors (H/10)
110Italian Ryegrass14056
54 November 17, 2016Lolium perenneNew ZealandNew Zealand 201530 Multiple Resistance: 3 Sites of Action
Carotenoid biosynthesis (unknown target) (F3/11)
EPSP synthase inhibitors (G/9)
Glutamine synthase inhibitors (H/10)
111Perennial Ryegrass14055
55 November 17, 2016Avena fatuaNew ZealandNew Zealand 201430 ACCase inhibitors (A/1)
28Wild Oat14054
56 November 2, 2016Bidens pilosaBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
32Hairy Beggarticks14053
57 October 27, 2016Tridax procumbensAustralia (Western Australia) AustraliaWestern Australia20161 EPSP synthase inhibitors (G/9)
333Coat Buttons14052
58 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
59 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
60 October 23, 2016Salsola tragusUnited States (Oregon) United StatesOregon201645 EPSP synthase inhibitors (G/9)
147Russian-thistle13055
61 October 19, 2016Oryza sativa var. sylvaticaGreeceGreece 201319 ALS inhibitors (B/2)
242Red Rice13054
62 October 19, 2016Lolium rigidumGreeceGreece 200919 ALS inhibitors (B/2)
112Rigid Ryegrass13053
63 October 19, 2016Echinochloa phyllopogon (=E. oryzicola)GreeceGreece 200919 ALS inhibitors (B/2)
178Late Watergrass13052
64 October 19, 2016Cyperus difformisGreeceGreece 200919 ALS inhibitors (B/2)
71Smallflower Umbrella Sedge13051
65 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
66 September 19, 2016Digitaria insularisArgentinaArgentina 201448 EPSP synthase inhibitors (G/9)
239Sourgrass13049
67 August 28, 2016Amaranthus palmeriUnited States (Nebraska) United StatesNebraska201445 Multiple Resistance: 2 Sites of Action
Photosystem II inhibitors (C1/5)
HPPD inhibitors (F2/27)
14Palmer Amaranth13048
68 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
69 August 22, 2016Oryza sativa var. sylvaticaUnited States (Arkansas) United StatesArkansas200245 ALS inhibitors (B/2)
242Red Rice13046
70 August 19, 2016Conyza bonariensisAustralia (New South Wales ) AustraliaNew South Wales 20161 PSI Electron Diverter (D/22)
60Hairy Fleabane13045
71 August 3, 2016Lolium perenne ssp. multiflorumUnited States (California) United StatesCalifornia201545 Glutamine synthase inhibitors (H/10)
110Italian Ryegrass13044
72 July 19, 2016Digitaria insularisBrazilBrazil 20165 ACCase inhibitors (A/1)
239Sourgrass13043
73 July 19, 2016Amaranthus palmeriBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
14Palmer Amaranth13042
74 December 18, 2016Amaranthus palmeriUnited States (California) United StatesCalifornia201545 EPSP synthase inhibitors (G/9)
14Palmer Amaranth13041
75 July 4, 2016Cyperus iriaBrazilBrazil 20145 ALS inhibitors (B/2)
266Rice Flatsedge13040
76 June 28, 2016Eleusine indicaBrazilBrazil 20165 EPSP synthase inhibitors (G/9)
81Goosegrass13039
77 May 24, 2016Amaranthus palmeriArgentinaArgentina 201548 EPSP synthase inhibitors (G/9)
14Palmer Amaranth13038
78 May 11, 2016Amaranthus palmeriUnited States (Tennessee) United StatesTennessee201545 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
14Palmer Amaranth13037
79 May 3, 2016Ambrosia artemisiifoliaUnited States (North Carolina) United StatesNorth Carolina201545 Multiple Resistance: 3 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
18Common Ragweed13036
80 May 2, 2016Chamaesyce maculataUnited States (Georgia) United StatesGeorgia201445 ALS inhibitors (B/2)
332Spotted Spurge13035
81 April 27, 2016Eleusine indicaIndonesiaIndonesia 201222 PSI Electron Diverter (D/22)
81Goosegrass13034
82 April 26, 2016Amaranthus retroflexusBrazilBrazil 20145 PPO inhibitors (E/14)
16Redroot Pigweed13033
83 April 18, 2016Echium plantagineumBrazilBrazil 20155 ALS inhibitors (B/2)
186Patersons Curse12033
84 March 3, 2016Salsola tragusUnited States (Montana) United StatesMontana201545 EPSP synthase inhibitors (G/9)
147Russian-thistle12032
85 February 25, 2016Avena fatuaCanada (Manitoba) CanadaManitoba20157 Multiple Resistance: 5 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
PPO inhibitors (E/14)
Long chain fatty acid inhibitors (K3/15)
Lipid Inhibitors (N/8)
28Wild Oat11033
86 February 25, 2016Kochia scopariaCanada (Saskatchewan) CanadaSaskatchewan20157 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
101Kochia11032
87 February 8, 2016Lolium rigidumAustralia (New South Wales ) AustraliaNew South Wales 20151 Lipid Inhibitors (N/8)
112Rigid Ryegrass11031
88 February 6, 2016Vulpia bromoidesAustralia (Western Australia) AustraliaWestern Australia20141 Photosystem II inhibitors (C1/5)
173Squirreltail Fescue11030
89 February 8, 2016Gamochaeta pensylvanicaAustralia (Queensland) AustraliaQueensland20151 PSI Electron Diverter (D/22)
298Pennsylvania Everlasting11029
90 February 8, 2016Chloris virgataAustralia (South Australia) AustraliaSouth Australia20151 EPSP synthase inhibitors (G/9)
330Feather Fingergrass11028
91 February 8, 2016Chloris virgataAustralia (Queensland) AustraliaQueensland20151 EPSP synthase inhibitors (G/9)
330Feather Fingergrass11027
92 February 8, 2016Chloris virgataAustralia (New South Wales ) AustraliaNew South Wales 20151 EPSP synthase inhibitors (G/9)
330Feather Fingergrass11026
93 February 8, 2016Solanum nigrumAustralia (Queensland) AustraliaQueensland20151 PSI Electron Diverter (D/22)
162Black Nightshade11025
94 February 8, 2016Eleusine indicaAustralia (Queensland) AustraliaQueensland20151 PSI Electron Diverter (D/22)
81Goosegrass11024
95 February 6, 2016Lolium rigidumAustralia (Victoria) AustraliaVictoria20151 Lipid Inhibitors (N/8)
112Rigid Ryegrass11023
96 February 8, 2016Lactuca serriolaAustralia (Victoria) AustraliaVictoria20151 EPSP synthase inhibitors (G/9)
102Prickly Lettuce11022
97 February 8, 2016Chloris truncataAustralia (Victoria) AustraliaVictoria20151 EPSP synthase inhibitors (G/9)
262Windmill Grass11021
98 April 27, 2016Eleusine indicaIndonesiaIndonesia 201222 Multiple Resistance: 2 Sites of Action
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
81Goosegrass11020
99 February 4, 2016Alopecurus aequalisJapanJapan 200625 ALS inhibitors (B/2)
264Shortawn Foxtail11019
100 February 4, 2016Alopecurus aequalisJapanJapan 200525 Microtubule inhibitors (K1/3)
264Shortawn Foxtail11018
101 February 4, 2016Atriplex patulaBelgiumBelgium 20153 Photosystem II inhibitors (C1/5)
26Halberdleaf Orach11017
102 February 2, 2016Echinochloa crus-galli var. crus-galliSpainSpain 201538 ALS inhibitors (B/2)
79Barnyardgrass11016
103 February 1, 2016Cyperus iriaVenezuelaVenezuela 201580 ALS inhibitors (B/2)
266Rice Flatsedge11015
104 February 1, 2016Alopecurus myosuroidesSpainSpain 201538 Multiple Resistance: 3 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
PSII inhibitor (Ureas and amides) (C2/7)
6Blackgrass11014
105 January 20, 2016Chenopodium albumFinlandFinland 2015139 ALS inhibitors (B/2)
47Common Lambsquarters11013
106 January 14, 2016Cyperus compressusUnited States (Alabama) United StatesAlabama201545 ALS inhibitors (B/2)
329Annual Sedge11012
107 January 10, 2016Conyza canadensisUnited States (Montana) United StatesMontana201545 EPSP synthase inhibitors (G/9)
61Horseweed11011
108 December 20, 2015Digitaria sanguinalisFranceFrance 201517 ALS inhibitors (B/2)
77Large Crabgrass11010
109 December 20, 2015Amaranthus palmeriBrazilBrazil 20155 EPSP synthase inhibitors (G/9)
14Palmer Amaranth11009
110 October 4, 2015Hirschfeldia incanaArgentinaArgentina 201348 ALS inhibitors (B/2)
328Shortpod Mustard11008
111 September 13, 2015Lolium perenne ssp. multiflorumSwitzerlandSwitzerland 201141 EPSP synthase inhibitors (G/9)
110Italian Ryegrass11007
112 May 9, 2017Amaranthus palmeriUnited States (Arkansas) United StatesArkansas201145 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
14Palmer Amaranth11006
113 September 2, 2015Amaranthus tuberculatus (=A. rudis)United States (Louisiana) United StatesLouisiana201545 EPSP synthase inhibitors (G/9)
219Tall Waterhemp11005
114 August 26, 2015Amaranthus tuberculatus (=A. rudis)United States (Minnesota) United StatesMinnesota201445 PPO inhibitors (E/14)
219Tall Waterhemp11004
115 August 21, 2015Parthenium hysterophorusUnited States (Florida) United StatesFlorida201445 EPSP synthase inhibitors (G/9)
124Ragweed Parthenium11003
116 August 20, 2015Polygonum lapathifoliumCanada (Alberta) CanadaAlberta20147 ALS inhibitors (B/2)
134Pale Smartweed11002
117 July 3, 2015Senecio vulgarisFranceFrance 200917 ALS inhibitors (B/2)
148Common Groundsel11001
118 June 29, 2015Sorghum halepenseSpainSpain 201538 ALS inhibitors (B/2)
166Johnsongrass11000
119 June 8, 2015Conyza canadensisJapanJapan 201425 EPSP synthase inhibitors (G/9)
61Horseweed10999
120 June 8, 2015Eleusine indicaJapanJapan 201325 EPSP synthase inhibitors (G/9)
81Goosegrass10998
121 June 8, 2015Echinochloa crus-galli var. formosensisJapanJapan 201025 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
304Taiwan barnyardgrass10997
122 May 12, 2015Apera spica-ventiSwedenSweden 200640 PSII inhibitor (Ureas and amides) (C2/7)
20Silky Windgrass10996
123 May 12, 2015Alopecurus myosuroidesSwedenSweden 201440 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
6Blackgrass10995
124 May 12, 2015Apera spica-ventiSwedenSweden 201040 ALS inhibitors (B/2)
20Silky Windgrass10994
125 April 28, 2015Senecio vernalisIsraelIsrael 201423 Multiple Resistance: 5 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
PSII inhibitor (Ureas and amides) (C2/7)
PPO inhibitors (E/14)
Carotenoid biosynthesis inhibitors (F1/12)
327Eastern Groundsel10993
126 April 28, 2015Lolium rigidumIsraelIsrael 201323 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
112Rigid Ryegrass10992
127 April 24, 2015Sorghum halepenseArgentinaArgentina 201548 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
EPSP synthase inhibitors (G/9)
166Johnsongrass10991
128 April 19, 2015Brachypodium distachyonIsraelIsrael 201423 ACCase inhibitors (A/1)
35Annual Falsebrome10990
129 April 15, 2015Sonchus oleraceusAustralia (South Australia) AustraliaSouth Australia20151 ALS inhibitors (B/2)
164Annual Sowthistle10989
130 April 15, 2015Sonchus oleraceusAustralia (South Australia) AustraliaSouth Australia20151 Synthetic Auxins (O/4)
164Annual Sowthistle10988
131 April 15, 2015Anthemis cotulaUnited States (Washington) United StatesWashington201045 ALS inhibitors (B/2)
19Mayweed Chamomile10987
132 April 11, 2015Kochia scopariaUnited States (North Dakota) United StatesNorth Dakota200445 Multiple Resistance: 2 Sites of Action
Photosystem II inhibitors (C1/5)
PSII inhibitor (Ureas and amides) (C2/7)
101Kochia10986
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