INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
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Herbicide Resistant Smallflower Umbrella Sedge Globally
(Cyperus difformis)
Herbicide Resistant Smallflower Umbrella Sedge Globally
(Cyperus difformis)
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Herbicide Resistant Smallflower Umbrella Sedge Globally
(Cyperus difformis)
#CountryFirstYearSituationActive IngredientsSite of Action
1 Australia (New South Wales ) AustraliaNew South Wales 1994 Rice bensulfuron-methyl 1 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge6
2 BrazilBrazil 2000 Rice cyclosulfamuron, and pyrazosulfuron-ethyl 5 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge5118
3 GreeceGreece 2009 Rice azimsulfuron, and halosulfuron-methyl 19 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge13051
4 IndiaIndia 2017 Rice bispyribac-sodium 21 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge23236
5 ItalyItaly 1999 Rice azimsulfuron, bensulfuron-methyl, and cinosulfuron 24 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge5155
6 PortugalPortugal 2023 Rice bentazon, and penoxsulam 34 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Histidine 215 Binders HRAC Group 6 (Legacy C3)
 		71Cyperus difformisSmallflower Umbrella Sedge28270
7 South KoreaSouth Korea 2002 Rice azimsulfuron, bensulfuron-methyl, cinosulfuron, cyclosulfamuron, ethoxysulfuron, halosulfuron-methyl, imazosulfuron, and pyrazosulfuron-ethyl 27 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge152
8 SpainSpain 2000 Rice bensulfuron-methyl, and penoxsulam 38 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge5140
9 TurkeyTurkey 2010 Rice azimsulfuron, bensulfuron-methyl, bispyribac-sodium, and penoxsulam 71 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge5532
10 United States (California) United StatesCalifornia1993 Rice bensulfuron-methyl 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge391
11 United States (Arkansas) United StatesArkansas2010 Rice halosulfuron-methyl 45 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Cyperus difformisSmallflower Umbrella Sedge5562
12 United States (California) United StatesCalifornia2013 Rice propanil 45 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		71Cyperus difformisSmallflower Umbrella Sedge6739
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