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 October 12, 2017Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 201648 Synthetic Auxins (O/4)
12Smooth Pigweed17108
2 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
3 October 5, 2017Ambrosia artemisiifoliaUnited States (Michigan) United StatesMichigan201645 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
18Common Ragweed17106
4 September 27, 2017Lolium rigidumSpainSpain 201638 Multiple Resistance: 2 Sites of Action
PPO inhibitors (E/14)
EPSP synthase inhibitors (G/9)
112Rigid Ryegrass17105
5 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
6 September 14, 2017Hirschfeldia incanaArgentinaArgentina 201648 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
328Shortpod Mustard17103
7 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
8 August 31, 2017Paspalum paniculatumCosta RicaCosta Rica 201011 EPSP synthase inhibitors (G/9)
335Arrocillo17101
9 August 27, 2017Conyza bonariensisArgentinaArgentina 201248 EPSP synthase inhibitors (G/9)
60Hairy Fleabane17100
10 August 6, 2017Conyza sumatrensisBrazilBrazil 20175 PPO inhibitors (E/14)
65Sumatran Fleabane17099
11 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
12 July 28, 2017Amaranthus palmeriUnited States (Wisconsin) United StatesWisconsin201445 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
HPPD inhibitors (F2/27)
14Palmer Amaranth16099
13 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
14 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16097
15 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Unknown (Z/27)
130Annual Bluegrass16096
16 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16095
17 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16094
18 July 13, 2017Poa annuaAustralia (New South Wales ) AustraliaNew South Wales 20171 ALS inhibitors (B/2)
130Annual Bluegrass16093
19 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16092
20 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16091
21 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16090
22 July 12, 2017Poa annuaAustralia (Victoria) AustraliaVictoria20171 ALS inhibitors (B/2)
130Annual Bluegrass16089
23 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 ALS inhibitors (B/2)
130Annual Bluegrass16088
24 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Microtubule inhibitors (K1/3)
130Annual Bluegrass16087
25 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Unknown (Z/27)
130Annual Bluegrass16086
26 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 Photosystem II inhibitors (C1/5)
130Annual Bluegrass16085
27 July 12, 2017Poa annuaAustralia (South Australia) AustraliaSouth Australia20171 EPSP synthase inhibitors (G/9)
130Annual Bluegrass16084
28 June 28, 2017Galium aparineIranIran 201679 Synthetic Auxins (O/4)
272Catchweed Bedstraw16083
29 June 28, 2017Conyza sumatrensisBrazilBrazil 20165 PSI Electron Diverter (D/22)
65Sumatran Fleabane16082
30 June 28, 2017Amaranthus spinosusUnited States (Mississippi) United StatesMississippi201345 ALS inhibitors (B/2)
278Spiny Amaranth16081
31 June 16, 2017Amaranthus tuberculatus (=A. rudis)United States (Mississippi) United StatesMississippi201045 ALS inhibitors (B/2)
219Tall Waterhemp16080
32 June 16, 2017Amaranthus retroflexusUnited States (Mississippi) United StatesMississippi201045 ALS inhibitors (B/2)
16Redroot Pigweed16079
33 May 16, 2017Amaranthus retroflexusChinaChina 20179 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
16Redroot Pigweed16078
34 May 12, 2017Conyza canadensisSouth KoreaSouth Korea 201727 EPSP synthase inhibitors (G/9)
61Horseweed16077
35 May 7, 2017Apera spica-ventiDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
20Silky Windgrass15078
36 May 7, 2017Lolium perenneDenmarkDenmark 201613 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
111Perennial Ryegrass15077
37 April 11, 2017Tripleurospermum perforatum (=T. inodorum)SwedenSweden 201540 ALS inhibitors (B/2)
116Scentless Chamomile15076
38 April 11, 2017Matricaria recutita (= M. chamomilla)SwedenSweden 201440 ALS inhibitors (B/2)
248Wild Chamomile15075
39 April 11, 2017Phalaris minorPakistanPakistan 201586 ACCase inhibitors (A/1)
127Little seed Canary grass15074
40 April 3, 2017Eleusine indicaUnited States (Virginia) United StatesVirginia201545 PPO inhibitors (E/14)
81Goosegrass15073
41 April 3, 2017Eleusine indicaUnited States (North Carolina) United StatesNorth Carolina201545 PPO inhibitors (E/14)
81Goosegrass15072
42 March 21, 2017Bromus tectorumUnited States (Montana) United StatesMontana201645 ALS inhibitors (B/2)
40Downy Brome (Cheatgrass)15071
43 March 20, 2017Conyza canadensisHungaryHungary 201620 EPSP synthase inhibitors (G/9)
61Horseweed15070
44 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
45 March 8, 2017Stellaria mediaLatviaLatvia 2016174 ALS inhibitors (B/2)
168Common Chickweed15068
46 March 8, 2017Apera spica-ventiLatviaLatvia 2015174 ALS inhibitors (B/2)
20Silky Windgrass15067
47 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
48 February 22, 2017Sorghum halepenseSerbiaSerbia 2014245 ALS inhibitors (B/2)
166Johnsongrass15065
49 July 28, 2017Galium aparineIranIran 201779 ALS inhibitors (B/2)
272Catchweed Bedstraw15064
50 June 6, 2017Lolium perenne ssp. multiflorumBrazilBrazil 20175 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
110Italian Ryegrass15063
51 February 9, 2017Helianthus annuusUnited States (Texas) United StatesTexas201545 EPSP synthase inhibitors (G/9)
95Common Sunflower15062
52 December 16, 2016Centaurea stoebe ssp. micranthosCanada (British Columbia) CanadaBritish Columbia20137 Synthetic Auxins (O/4)
334Spotted knapweed15061
53 December 18, 2016Avena fatuaSyriaSyria 201569 ACCase inhibitors (A/1)
28Wild Oat15060
54 December 18, 2016Phalaris paradoxaSyriaSyria 201569 ACCase inhibitors (A/1)
128Hood Canarygrass15059
55 December 18, 2016Phalaris brachystachysSyriaSyria 201569 ACCase inhibitors (A/1)
244Shortspike Canarygrass15058
56 December 12, 2016Lolium perenne ssp. multiflorumBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
110Italian Ryegrass15057
57 December 2, 2016Sonchus oleraceusAustralia (Victoria) AustraliaVictoria20151 Synthetic Auxins (O/4)
164Annual Sowthistle15056
58 December 2, 2016Arctotheca calendulaAustralia (South Australia) AustraliaSouth Australia20151 Synthetic Auxins (O/4)
21Capeweed15055
59 November 27, 2016Papaver rhoeasFranceFrance 201617 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
123Corn Poppy15054
60 November 21, 2016Sonchus asperFranceFrance 201517 ALS inhibitors (B/2)
163Spiny Sowthistle14058
61 November 17, 2016Ranunculus acrisNew ZealandNew Zealand 201030 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
140Tall Buttercup14057
62 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
63 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
64 November 17, 2016Avena fatuaNew ZealandNew Zealand 201430 ACCase inhibitors (A/1)
28Wild Oat14054
65 November 2, 2016Bidens pilosaBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Photosystem II inhibitors (C1/5)
32Hairy Beggarticks14053
66 October 27, 2016Tridax procumbensAustralia (Western Australia) AustraliaWestern Australia20161 EPSP synthase inhibitors (G/9)
333Coat Buttons14052
67 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
68 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
69 October 23, 2016Salsola tragusUnited States (Oregon) United StatesOregon201645 EPSP synthase inhibitors (G/9)
147Russian-thistle13055
70 October 19, 2016Oryza sativa var. sylvaticaGreeceGreece 201319 ALS inhibitors (B/2)
242Red Rice13054
71 October 19, 2016Lolium rigidumGreeceGreece 200919 ALS inhibitors (B/2)
112Rigid Ryegrass13053
72 October 19, 2016Echinochloa phyllopogon (=E. oryzicola)GreeceGreece 200919 ALS inhibitors (B/2)
178Late Watergrass13052
73 October 19, 2016Cyperus difformisGreeceGreece 200919 ALS inhibitors (B/2)
71Smallflower Umbrella Sedge13051
74 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
75 September 19, 2016Digitaria insularisArgentinaArgentina 201448 EPSP synthase inhibitors (G/9)
239Sourgrass13049
76 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
77 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
78 August 22, 2016Oryza sativa var. sylvaticaUnited States (Arkansas) United StatesArkansas200245 ALS inhibitors (B/2)
242Red Rice13046
79 August 19, 2016Conyza bonariensisAustralia (New South Wales ) AustraliaNew South Wales 20161 PSI Electron Diverter (D/22)
60Hairy Fleabane13045
80 August 3, 2016Lolium perenne ssp. multiflorumUnited States (California) United StatesCalifornia201545 Glutamine synthase inhibitors (H/10)
110Italian Ryegrass13044
81 July 19, 2016Digitaria insularisBrazilBrazil 20165 ACCase inhibitors (A/1)
239Sourgrass13043
82 July 19, 2016Amaranthus palmeriBrazilBrazil 20165 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
14Palmer Amaranth13042
83 December 18, 2016Amaranthus palmeriUnited States (California) United StatesCalifornia201545 EPSP synthase inhibitors (G/9)
14Palmer Amaranth13041
84 July 4, 2016Cyperus iriaBrazilBrazil 20145 ALS inhibitors (B/2)
266Rice Flatsedge13040
85 June 28, 2016Eleusine indicaBrazilBrazil 20165 EPSP synthase inhibitors (G/9)
81Goosegrass13039
86 May 24, 2016Amaranthus palmeriArgentinaArgentina 201548 EPSP synthase inhibitors (G/9)
14Palmer Amaranth13038
87 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
88 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
89 May 2, 2016Chamaesyce maculataUnited States (Georgia) United StatesGeorgia201445 ALS inhibitors (B/2)
332Spotted Spurge13035
90 April 27, 2016Eleusine indicaIndonesiaIndonesia 201222 PSI Electron Diverter (D/22)
81Goosegrass13034
91 April 26, 2016Amaranthus retroflexusBrazilBrazil 20145 PPO inhibitors (E/14)
16Redroot Pigweed13033
92 April 18, 2016Echium plantagineumBrazilBrazil 20155 ALS inhibitors (B/2)
186Patersons Curse12033
93 March 3, 2016Salsola tragusUnited States (Montana) United StatesMontana201545 EPSP synthase inhibitors (G/9)
147Russian-thistle12032
94 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
95 February 25, 2016Kochia scopariaCanada (Saskatchewan) CanadaSaskatchewan20157 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
Synthetic Auxins (O/4)
101Kochia11032
96 February 8, 2016Lolium rigidumAustralia (New South Wales ) AustraliaNew South Wales 20151 Lipid Inhibitors (N/8)
112Rigid Ryegrass11031
97 February 6, 2016Vulpia bromoidesAustralia (Western Australia) AustraliaWestern Australia20141 Photosystem II inhibitors (C1/5)
173Squirreltail Fescue11030
98 February 8, 2016Gamochaeta pensylvanicaAustralia (Queensland) AustraliaQueensland20151 PSI Electron Diverter (D/22)
298Pennsylvania Everlasting11029
99 February 8, 2016Chloris virgataAustralia (South Australia) AustraliaSouth Australia20151 EPSP synthase inhibitors (G/9)
330Feather Fingergrass11028
100 February 8, 2016Chloris virgataAustralia (Queensland) AustraliaQueensland20151 EPSP synthase inhibitors (G/9)
330Feather Fingergrass11027
101 February 8, 2016Chloris virgataAustralia (New South Wales ) AustraliaNew South Wales 20151 EPSP synthase inhibitors (G/9)
330Feather Fingergrass11026
102 February 8, 2016Solanum nigrumAustralia (Queensland) AustraliaQueensland20151 PSI Electron Diverter (D/22)
162Black Nightshade11025
103 February 8, 2016Eleusine indicaAustralia (Queensland) AustraliaQueensland20151 PSI Electron Diverter (D/22)
81Goosegrass11024
104 February 6, 2016Lolium rigidumAustralia (Victoria) AustraliaVictoria20151 Lipid Inhibitors (N/8)
112Rigid Ryegrass11023
105 February 8, 2016Lactuca serriolaAustralia (Victoria) AustraliaVictoria20151 EPSP synthase inhibitors (G/9)
102Prickly Lettuce11022
106 February 8, 2016Chloris truncataAustralia (Victoria) AustraliaVictoria20151 EPSP synthase inhibitors (G/9)
262Windmill Grass11021
107 April 27, 2016Eleusine indicaIndonesiaIndonesia 201222 Multiple Resistance: 2 Sites of Action
PSI Electron Diverter (D/22)
EPSP synthase inhibitors (G/9)
81Goosegrass11020
108 February 4, 2016Alopecurus aequalisJapanJapan 200625 ALS inhibitors (B/2)
264Shortawn Foxtail11019
109 February 4, 2016Alopecurus aequalisJapanJapan 200525 Microtubule inhibitors (K1/3)
264Shortawn Foxtail11018
110 February 4, 2016Atriplex patulaBelgiumBelgium 20153 Photosystem II inhibitors (C1/5)
26Halberdleaf Orach11017
111 February 2, 2016Echinochloa crus-galli var. crus-galliSpainSpain 201538 ALS inhibitors (B/2)
79Barnyardgrass11016
112 February 1, 2016Cyperus iriaVenezuelaVenezuela 201580 ALS inhibitors (B/2)
266Rice Flatsedge11015
113 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
114 January 20, 2016Chenopodium albumFinlandFinland 2015139 ALS inhibitors (B/2)
47Common Lambsquarters11013
115 January 14, 2016Cyperus compressusUnited States (Alabama) United StatesAlabama201545 ALS inhibitors (B/2)
329Annual Sedge11012
116 January 10, 2016Conyza canadensisUnited States (Montana) United StatesMontana201545 EPSP synthase inhibitors (G/9)
61Horseweed11011
117 December 20, 2015Digitaria sanguinalisFranceFrance 201517 ALS inhibitors (B/2)
77Large Crabgrass11010
118 December 20, 2015Amaranthus palmeriBrazilBrazil 20155 EPSP synthase inhibitors (G/9)
14Palmer Amaranth11009
119 October 4, 2015Hirschfeldia incanaArgentinaArgentina 201348 ALS inhibitors (B/2)
328Shortpod Mustard11008
120 September 13, 2015Lolium perenne ssp. multiflorumSwitzerlandSwitzerland 201141 EPSP synthase inhibitors (G/9)
110Italian Ryegrass11007
121 May 9, 2017Amaranthus palmeriUnited States (Arkansas) United StatesArkansas201145 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
PPO inhibitors (E/14)
14Palmer Amaranth11006
122 September 2, 2015Amaranthus tuberculatus (=A. rudis)United States (Louisiana) United StatesLouisiana201545 EPSP synthase inhibitors (G/9)
219Tall Waterhemp11005
123 August 26, 2015Amaranthus tuberculatus (=A. rudis)United States (Minnesota) United StatesMinnesota201445 PPO inhibitors (E/14)
219Tall Waterhemp11004
124 August 21, 2015Parthenium hysterophorusUnited States (Florida) United StatesFlorida201445 EPSP synthase inhibitors (G/9)
124Ragweed Parthenium11003
125 August 20, 2015Polygonum lapathifoliumCanada (Alberta) CanadaAlberta20147 ALS inhibitors (B/2)
134Pale Smartweed11002
126 July 3, 2015Senecio vulgarisFranceFrance 200917 ALS inhibitors (B/2)
148Common Groundsel11001
127 June 29, 2015Sorghum halepenseSpainSpain 201538 ALS inhibitors (B/2)
166Johnsongrass11000
128 June 8, 2015Conyza canadensisJapanJapan 201425 EPSP synthase inhibitors (G/9)
61Horseweed10999
129 June 8, 2015Eleusine indicaJapanJapan 201325 EPSP synthase inhibitors (G/9)
81Goosegrass10998
130 June 8, 2015Echinochloa crus-galli var. formosensisJapanJapan 201025 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
304Taiwan barnyardgrass10997
131 May 12, 2015Apera spica-ventiSwedenSweden 200640 PSII inhibitor (Ureas and amides) (C2/7)
20Silky Windgrass10996
132 May 12, 2015Alopecurus myosuroidesSwedenSweden 201440 Multiple Resistance: 2 Sites of Action
ACCase inhibitors (A/1)
ALS inhibitors (B/2)
6Blackgrass10995
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