INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE

HRAC GROUP 9 (LEGACY G) RESISTANT ANNUAL BLUEGRASS
(Poa annua)

Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)

United States, Tennessee
INTRODUCTION ANNUAL BLUEGRASS
Annual Bluegrass (Poa annua) is a monocot weed in the Poaceae family.  In Tennessee this weed first evolved resistance to Group 9 (Legacy G) herbicides in 2011 and infests Golf courses, and Turf.   Group 9 (Legacy G) herbicides are known as Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (Inhibition of EPSP synthase).  Research has shown that these particular biotypes are resistant to glyphosate and they may be cross-resistant to other Group 9 (Legacy G) herbicides.

The 'Group' letters/numbers that you see throughout this web site refer to the classification of herbicides by their site of action. To see a full list of herbicides and HRAC herbicide classifications click here.

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QUIK STATS (last updated Dec 10, 2013 )

Common NameAnnual Bluegrass
SpeciesPoa annua
GroupInhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
Herbicidesglyphosate
LocationUnited States, Tennessee
Year2011
Situation(s)Golf courses, and Turf
Contributors - (Alphabetically)James Brosnan, and Larry Steckel 
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ACADEMIC ASPECTS

Confirmation Tests

Greenhouse trials comparing a known susceptible Annual Bluegrass biotype with this Annual Bluegrass biotype have been used to confirm resistance. For further information on the tests conducted please contact the local weed scientists that provided this information.
 
Genetics

Genetic studies on HRAC Group 9 resistant Annual Bluegrass have not been reported to the site.  There may be a note below or an article discussing the genetics of this biotype in the Fact Sheets and Other Literature
 
Mechanism of Resistance

The mechanism of resistance for this biotype is either unknown or has not been entered in the database.  If you know anything about the mechanism of resistance for this biotype then please update the database.
 
Relative Fitness

There is no record of differences in fitness or competitiveness of these resistant biotypes when compared to that of normal susceptible biotypes.  If you have any information pertaining to the fitness of Group 9 (Legacy G) resistant Annual Bluegrass from Tennessee please update the database.
 
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CONTRIBUTING WEED SCIENTISTS

JAMES BROSNAN
Associate Professor
University Of Tennessee
Plant Science - Turfgrass Weed Science
212 Plant Biotech Bldg 2431 Joe Johnson Dr.
Knoxville, 37996, Tennessee
United States
Email James Brosnan
Web   : Web Site Link
LARRY STECKEL
Research and Extension Weed Specialist
University Of Tennessee
Department of Plant Sciences
605 Airways Blvd.
Jackson, 38301, Tennessee
United States
Email Larry Steckel
Web   : Web Site Link

ACKNOWLEDGEMENTS

The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Tennessee have been instrumental in providing you this information. Particular thanks is given to James Brosnan, and Larry Steckel for providing detailed information.
Herbicide Resistant Annual Bluegrass Globally
(Poa annua)
Herbicide Resistant Annual Bluegrass Globally
(Poa annua)
Drag a column header and drop it here to group by that column
Herbicide Resistant Annual Bluegrass Globally
(Poa annua)
#CountryFirstYearSituationActive IngredientsSite of Action
1 Australia (Victoria) AustraliaVictoria2009 Golf courses, and Turf endothall 1 Unknown ( HRAC Group 0 (Legacy Z)
 		130Poa annuaAnnual Bluegrass5513
2 Australia (South Australia) AustraliaSouth Australia2017 Golf courses glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		130Poa annuaAnnual Bluegrass16084
3 Australia (South Australia) AustraliaSouth Australia2017 Golf courses simazine 1 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass16085
4 Australia (South Australia) AustraliaSouth Australia2017 Golf courses endothall 1 Unknown ( HRAC Group 0 (Legacy Z)
 		130Poa annuaAnnual Bluegrass16086
5 Australia (South Australia) AustraliaSouth Australia2017 Golf courses propyzamide/pronamide 1 Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
 		130Poa annuaAnnual Bluegrass16087
6 Australia (South Australia) AustraliaSouth Australia2017 Golf courses bispyribac-sodium, foramsulfuron, iodosulfuron-methyl-Na, and rimsulfuron 1 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass16088
7 Australia (Victoria) AustraliaVictoria2017 Golf courses bispyribac-sodium, foramsulfuron, iodosulfuron-methyl-Na, and rimsulfuron 1 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass16089
8 Australia (Victoria) AustraliaVictoria2017 Golf courses simazine 1 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass16090
9 Australia (Victoria) AustraliaVictoria2017 Golf courses glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		130Poa annuaAnnual Bluegrass16091
10 Australia (Victoria) AustraliaVictoria2017 Golf courses propyzamide/pronamide 1 Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
 		130Poa annuaAnnual Bluegrass16092
11 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses bispyribac-sodium, foramsulfuron, iodosulfuron-methyl-Na, and rimsulfuron 1 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass16093
12 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses simazine 1 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass16094
13 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses glyphosate 1 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		130Poa annuaAnnual Bluegrass16095
14 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses endothall 1 Unknown ( HRAC Group 0 (Legacy Z)
 		130Poa annuaAnnual Bluegrass16096
15 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses propyzamide/pronamide 1 Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
 		130Poa annuaAnnual Bluegrass16097
16 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses bispyribac-sodium, endothall, foramsulfuron, glyphosate, iodosulfuron-methyl-Na, propyzamide/pronamide, rimsulfuron, and simazine 1 Multiple Resistance: 5 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
Unknown ( HRAC Group 0 (Legacy Z)
 		130Poa annuaAnnual Bluegrass16098
17 Australia (New South Wales ) AustraliaNew South Wales 2017 Golf courses pinoxaden 1 Inhibition of Acetyl CoA Carboxylase ( HRAC Group 1 (Legacy A)
 		130Poa annuaAnnual Bluegrass18189
18 Australia (Victoria) AustraliaVictoria2017 Golf courses pinoxaden 1 Inhibition of Acetyl CoA Carboxylase ( HRAC Group 1 (Legacy A)
 		130Poa annuaAnnual Bluegrass18190
19 BelgiumBelgium 1981 Nurseries, Orchards, and Roadsides simazine 3 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass33
20 BelgiumBelgium 1983 Orchards amitrole 3 Inhibition of Lycopene Cyclase ( HRAC Group 34 (Legacy F3)
 		130Poa annuaAnnual Bluegrass38
21 BelgiumBelgium 1993 Hops paraquat 3 PS I Electron Diversion ( HRAC Group 22 (Legacy D)
 		130Poa annuaAnnual Bluegrass36
22 Czech RepublicCzech Republic 1988 Orchards, and Railways atrazine, cyanazine, prometryne, and terbutryne 12 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass85
23 FranceFrance 1978 Orchards atrazine 17 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass464
24 FranceFrance 2015 Wheat iodosulfuron-methyl-Na, and mesosulfuron-methyl 17 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass18180
25 GermanyGermany 1980 Orchards atrazine 18 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass449
26 IrelandIreland 2021 Wheat iodosulfuron-methyl-Na, mesosulfuron-methyl, pinoxaden, propaquizafop, and pyroxsulam 81 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase ( HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass27262
27 JapanJapan 1982 Golf courses, and Turf simazine 25 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass117
28 NetherlandsNetherlands 1981 Orchards simazine 43 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass219
29 New ZealandNew Zealand 2020 Turf haloxyfop-methyl 30 Inhibition of Acetyl CoA Carboxylase ( HRAC Group 1 (Legacy A)
 		130Poa annuaAnnual Bluegrass18203
30 NorwayNorway 1996 Nurseries simazine 31 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass388
31 United KingdomUnited Kingdom 1981 Hops paraquat 44 PS I Electron Diversion ( HRAC Group 22 (Legacy D)
 		130Poa annuaAnnual Bluegrass359
32 United KingdomUnited Kingdom 1981 Orchards simazine 44 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass366
33 United States (Alabama) United StatesAlabama1980 Pastures simazine 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass1166
34 United States (Oregon) United StatesOregon1994 Grass seed ethofumesate 45 Very Long-Chain Fatty Acid Synthesis inhibitors ( HRAC Group 15 (Legacy K3 N)
 		130Poa annuaAnnual Bluegrass334
35 United States (Oregon) United StatesOregon1994 Grass seed diuron 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass336
36 United States (Oregon) United StatesOregon1994 Grass seed atrazine 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass338
37 United States (North Carolina) United StatesNorth Carolina1995 Golf courses, and Turf simazine 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass1060
38 United States (Mississippi) United StatesMississippi1996 Turf atrazine, and simazine 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass1187
39 United States (North Carolina) United StatesNorth Carolina1997 Golf courses, and Turf pendimethalin, and prodiamine 45 Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
 		130Poa annuaAnnual Bluegrass1165
40 United States (Oregon) United StatesOregon2000 Grass seed diuron, and metribuzin 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass18181
41 United States (Virginia) United StatesVirginia2001 Golf courses, and Turf simazine 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		130Poa annuaAnnual Bluegrass5162
42 United States (Tennessee) United StatesTennessee2007 Golf courses, and Turf dithiopyr, pendimethalin, and prodiamine 45 Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
 		130Poa annuaAnnual Bluegrass5645
43 United States (Missouri) United StatesMissouri2010 Turf glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		130Poa annuaAnnual Bluegrass5495
44 United States (Tennessee) United StatesTennessee2011 Golf courses, and Turf glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		130Poa annuaAnnual Bluegrass5596
45 United States (Alabama) United StatesAlabama2012 Turf bispyribac-sodium, foramsulfuron, imazaquin, and trifloxysulfuron-Na 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass5644
46 United States (Alabama) United StatesAlabama2012 Turf dithiopyr, pendimethalin, and prodiamine 45 Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
 		130Poa annuaAnnual Bluegrass5695
47 United States (Tennessee) United StatesTennessee2013 Golf courses, and Turf foramsulfuron, simazine, and trifloxysulfuron-Na 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)
 		130Poa annuaAnnual Bluegrass6765
48 United States (California) United StatesCalifornia2013 Almonds glyphosate 45 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		130Poa annuaAnnual Bluegrass7805
49 United States (Mississippi) United StatesMississippi2014 Golf courses foramsulfuron 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
 		130Poa annuaAnnual Bluegrass10982
50 United States (Tennessee) United StatesTennessee2017 Golf courses flumioxazin, foramsulfuron, glufosinate-ammonium, glyphosate, Indaziflam, metribuzin, prodiamine, propyzamide/pronamide, and simazine 45 Multiple Resistance: 7 Sites of Action
Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
Inhibition of Protoporphyrinogen Oxidase ( HRAC Group 14 (Legacy E)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
Inhibition of Glutamine Synthetase ( HRAC Group 10 (Legacy H)
Inhibition of Microtubule Assembly ( HRAC Group 3 (Legacy K1)
Inhibition of Cellulose Synthesis ( HRAC Group 29 (Legacy L)
 		130Poa annuaAnnual Bluegrass23237
51 United States (Georgia) United StatesGeorgia2022 Golf courses Indaziflam 45 Inhibition of Cellulose Synthesis ( HRAC Group 29 (Legacy L)
 		130Poa annuaAnnual Bluegrass25260
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