International Survey of Herbicide-Resistant Weeds

Countries Weeds Herbicides Mutations Graphs References Researchers
HRAC GROUP 5 (LEGACY C1 C2) RESISTANT SWOLLEN FINGERGRASS
(Chloris barbata = (C. inflate))

PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)

United States, Hawaii
INTRODUCTION SWOLLEN FINGERGRASS
Swollen Fingergrass (Chloris barbata = (C. inflate)) is a monocot weed in the Poaceae family.  In Hawaii this weed first evolved resistance to Group 5 (Legacy C1 C2) herbicides in 1987 and infests Roadsides, and Sugarcane for sugar.   Group 5 (Legacy C1 C2) herbicides are known as PSII inhibitors - Serine 264 Binders (Inhbition of Photosynthesis at PSll - Serine 264 Binders ).  Research has shown that these particular biotypes are resistant to ametryne and they may be cross-resistant to other Group 5 (Legacy C1 C2) 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 Sep 15, 2000 )

Common NameSwollen Fingergrass
SpeciesChloris barbata = (C. inflate)
GroupPSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
Herbicidesametryne
LocationUnited States, Hawaii
Year1987
Situation(s)Roadsides, and Sugarcane for sugar
Contributors - (Alphabetically)Lance Santo 
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NOTES ABOUT THIS BIOTYPE

AREAS FOUND

Lance Santo
Maui, Honolulu, and Kauai counties.

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GENERAL

Lance Santo
Resistance 1st observed on field edges. Seeds from the field edges moved into the fields in the following crop by wind, tillage, and water.

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ACADEMIC ASPECTS

Confirmation Tests

Field, and Greenhouse trials comparing a known susceptible Swollen Fingergrass biotype with this Swollen Fingergrass 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 5 resistant Swollen Fingergrass 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 5 (Legacy C1 C2) resistant Swollen Fingergrass from Hawaii please update the database.
 
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CONTRIBUTING WEED SCIENTISTS

LANCE SANTO
Agronomist/Field Coordinator
Hawaii Agriculture Research Center
Pesticide And Residue
94-340 Kunia Road
Waipahu, 96797, Hawaii
United States
Email Lance Santo
Web   : Web Site Link

ACKNOWLEDGEMENTS

The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Hawaii have been instrumental in providing you this information. Particular thanks is given to Lance Santo for providing detailed information.
Herbicide Resistant Swollen Fingergrass Globally
(Chloris barbata = (C. inflate))
Herbicide Resistant Swollen Fingergrass Globally
(Chloris barbata = (C. inflate))
Drag a column header and drop it here to group by that column
Herbicide Resistant Swollen Fingergrass Globally
(Chloris barbata = (C. inflate))
#CountryFirstYearSituationActive IngredientsSite of Action
1 MexicoMexico 2018 Oranges glyphosate 29 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ( HRAC Group 9 (Legacy G)
 		53Chloris barbata = (C. inflate)Swollen Fingergrass18197
2 United States (Hawaii) United StatesHawaii1987 Roadsides, and Sugarcane for sugar ametryne 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		53Chloris barbata = (C. inflate)Swollen Fingergrass227
3 United States (Hawaii) United StatesHawaii1987 Roadsides, and Sugarcane for sugar diuron 45 PSII inhibitors - Serine 264 Binders ( HRAC Group 5 (Legacy C1 C2)
 		53Chloris barbata = (C. inflate)Swollen Fingergrass228
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