INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
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Herbicide Resistant Giant Ragweed Globally
(Ambrosia trifida)
Herbicide Resistant Giant Ragweed Globally
(Ambrosia trifida)
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Herbicide Resistant Giant Ragweed Globally
(Ambrosia trifida)
#CountryFirstYearSituationActive IngredientsSite of Action
1 Canada (Ontario) CanadaOntario2008 Soybean glyphosate 7 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5483
2 Canada (Ontario) CanadaOntario2011 Soybean cloransulam-methyl, and glyphosate 7 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)
 		184Ambrosia trifidaGiant Ragweed7833
3 United States (Indiana) United StatesIndiana1998 Soybean cloransulam-methyl, and imazethapyr 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		184Ambrosia trifidaGiant Ragweed1123
4 United States (Illinois) United StatesIllinois1998 Soybean cloransulam-methyl, and imazethapyr 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		184Ambrosia trifidaGiant Ragweed1124
5 United States (Ohio) United StatesOhio1998 Soybean chlorimuron-ethyl, cloransulam-methyl, imazamox, imazaquin, primisulfuron-methyl, and prosulfuron 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		184Ambrosia trifidaGiant Ragweed1164
6 United States (Iowa) United StatesIowa2000 Corn (maize), and Soybean cloransulam-methyl, primisulfuron-methyl, and prosulfuron 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		184Ambrosia trifidaGiant Ragweed5231
7 United States (Ohio) United StatesOhio2004 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5278
8 United States (Indiana) United StatesIndiana2005 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5279
9 United States (Arkansas) United StatesArkansas2005 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5345
10 United States (Kentucky) United StatesKentucky2005 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed7878
11 United States (Kansas) United StatesKansas2006 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5304
12 United States (Minnesota) United StatesMinnesota2006 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5333
13 United States (Ohio) United StatesOhio2006 Soybean chlorimuron-ethyl, cloransulam-methyl, and glyphosate 45 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)
 		184Ambrosia trifidaGiant Ragweed5408
14 United States (Tennessee) United StatesTennessee2007 Cotton, and Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5335
15 United States (Minnesota) United StatesMinnesota2008 Soybean cloransulam-methyl, and glyphosate 45 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)
 		184Ambrosia trifidaGiant Ragweed5508
16 United States (Iowa) United StatesIowa2009 Corn (maize), and Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5463
17 United States (Missouri) United StatesMissouri2009 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5466
18 United States (Mississippi) United StatesMississippi2010 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5504
19 United States (Nebraska) United StatesNebraska2010 Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5573
20 United States (Wisconsin) United StatesWisconsin2011 Corn (maize), and Soybean glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		184Ambrosia trifidaGiant Ragweed5660
21 United States (Missouri) United StatesMissouri2011 Corn (maize) chlorimuron-ethyl, cloransulam-methyl, and glyphosate 45 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)
 		184Ambrosia trifidaGiant Ragweed7808
22 United States (Wisconsin) United StatesWisconsin2013 Soybean cloransulam-methyl, and imazamox 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		184Ambrosia trifidaGiant Ragweed7822
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