INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
select
select
Herbicide Resistant Smooth Pigweed Globally
(Amaranthus hybridus (syn: quitensis))
Herbicide Resistant Smooth Pigweed Globally
(Amaranthus hybridus (syn: quitensis))
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Herbicide Resistant Smooth Pigweed Globally
(Amaranthus hybridus (syn: quitensis))
#CountryFirstYearSituationActive IngredientsSite of Action
1 ArgentinaArgentina 1996 Soybean chlorimuron-ethyl, and imazethapyr 48 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5099
2 ArgentinaArgentina 2013 Soybean glyphosate 48 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed6757
3 ArgentinaArgentina 2014 Corn (maize), and Soybean glyphosate, and imazethapyr 48 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed9948
4 ArgentinaArgentina 2016 Soybean 2,4-D, dicamba, and glyphosate 48 Multiple Resistance: 2 Sites of Action
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
Auxin Mimics HRAC Group 4 (Legacy O)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed17107
5 ArgentinaArgentina 2016 Soybean 2,4-D, and dicamba 48 Auxin Mimics HRAC Group 4 (Legacy O)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed17108
6 ArgentinaArgentina 2021 Soybean fomesafen 48 Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed23243
7 BoliviaBolivia 2002 Soybean chlorimuron-ethyl, imazamox, imazethapyr, and oxasulfuron 4 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5242
8 BoliviaBolivia 2005 Soybean fomesafen, lactofen, and sulfentrazone 4 Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5411
9 BoliviaBolivia 2015 Soybean glyphosate 4 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed32281
10 BrazilBrazil 2018 Soybean chlorimuron-ethyl, and glyphosate 5 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed18184
11 Canada (Ontario) CanadaOntario2004 Corn (maize) bentazon, and bromoxynil 7 PSII inhibitors - Histidine 215 Binders HRAC Group 6 (Legacy C3)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5472
12 FranceFrance 1980 Corn (maize) atrazine 17 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed453
13 IsraelIsrael 1986 Cropland atrazine 23 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed101
14 ItalyItaly 1978 Corn (maize) atrazine 24 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed114
15 ItalyItaly 2018 Soybean imazamox, and thifensulfuron-methyl 24 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed27281
16 ParaguayParaguay 2022 Corn (maize), and Soybean chlorimuron-ethyl, and glyphosate 46 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed24252
17 South AfricaSouth Africa 1993 Corn (maize) atrazine 37 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed193
18 South AfricaSouth Africa 2024 Corn (maize), and Soybean glyphosate 37 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed27287
19 SpainSpain 1985 Corn (maize) atrazine 38 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed175
20 SwitzerlandSwitzerland 1982 Vegetables simazine 41 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed198
21 United States (Maryland) United StatesMaryland1972 Corn (maize), and Cropland atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed429
22 United States (Virginia) United StatesVirginia1976 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed273
23 United States (Delaware) United StatesDelaware1977 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed492
24 United States (North Carolina) United StatesNorth Carolina1980 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed262
25 United States (Pennsylvania) United StatesPennsylvania1980 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed264
26 United States (New Jersey) United StatesNew Jersey1980 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed494
27 United States (New York) United StatesNew York1980 Corn (maize) atrazine, metribuzin, and simazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5225
28 United States (Wisconsin) United StatesWisconsin1985 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed418
29 United States (Kentucky) United StatesKentucky1987 Corn (maize) atrazine, and simazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed489
30 United States (Kentucky) United StatesKentucky1992 Soybean chlorimuron-ethyl, flumetsulam, imazaquin, imazethapyr, nicosulfuron, primisulfuron-methyl, and thifensulfuron-methyl 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed490
31 United States (Illinois) United StatesIllinois1993 Corn (maize) atrazine 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed236
32 United States (Virginia) United StatesVirginia1994 Corn (maize), and Soybean imazaquin, and imazethapyr 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed278
33 United States (Illinois) United StatesIllinois1998 Soybean imazethapyr, and primisulfuron-methyl 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed7859
34 United States (Delaware) United StatesDelaware2000 Vegetables imazethapyr 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5160
35 United States (Illinois) United StatesIllinois2000 Corn (maize) atrazine, imazethapyr, and primisulfuron-methyl 45 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed7860
36 United States (Ohio) United StatesOhio2001 Soybean flumetsulam, and thifensulfuron-methyl 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5233
37 United States (Michigan) United StatesMichigan2002 Soybean chlorimuron-ethyl, imazamox, and thifensulfuron-methyl 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed5170
38 UruguayUruguay 2022 Corn (maize), and Soybean glyphosate 73 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Amaranthus hybridus (syn: quitensis)Smooth Pigweed24255
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