INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE

HRAC GROUP 2 (LEGACY B) RESISTANT COMMON COCKLEBUR
(Xanthium strumarium)


Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)

United States, Maryland
INTRODUCTION COMMON COCKLEBUR
Common cocklebur (Xanthium strumarium) is a dicot weed in the Asteraceae family.  In Maryland this weed first evolved resistance to Group 2 (Legacy B) herbicides in 1998 and infests Unspecified.   Group 2 (Legacy B) herbicides are known as Inhibition of Acetolactate Synthase (Inhibition of Acetolactate Synthase ).  Research has shown that these particular biotypes are resistant to chlorimuron-ethyl, imazaquin, and imazethapyr and they may be cross-resistant to other Group 2 (Legacy B) 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.

If we do not have a picture for this weed, or you can provide a better picture (scan, digital camera etc) please please e-mail it to us.

QUIK STATS (last updated Sep 15, 2000 )

Common NameCommon cocklebur
SpeciesXanthium strumarium
GroupInhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Herbicideschlorimuron-ethyl, imazaquin, and imazethapyr
LocationUnited States, Maryland
Year1998
Situation(s)Unspecified
Contributors - (Alphabetically)Ronald Ritter 
Edit this Case  |  Add New Case of Resistance  |  Add Note

ACADEMIC ASPECTS

Confirmation Tests

Greenhouse trials comparing a known susceptible Common cocklebur biotype with this Common cocklebur 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 2 resistant Common cocklebur 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 2 (Legacy B) resistant Common cocklebur from Maryland please update the database.
 
Edit Case  |  Add Note  |  Add Article  |  Add New Case  |  

CONTRIBUTING WEED SCIENTISTS

RONALD RITTER
Professor
University Of Maryland
Plant Science and Landscape Architecture
1118 H. J. Patterson Hall
College Park, 20742 , Maryland
United States
Email Ronald Ritter
Web   : Web Site Link

ACKNOWLEDGEMENTS

The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Maryland have been instrumental in providing you this information. Particular thanks is given to Ronald Ritter for providing detailed information.
Herbicide Resistant Common cocklebur Globally
(Xanthium strumarium)
Herbicide Resistant Common cocklebur Globally
(Xanthium strumarium)
Drag a column header and drop it here to group by that column
Herbicide Resistant Common cocklebur Globally
(Xanthium strumarium)
#CountryFirstYearSituationActive IngredientsSite of Action
1 KazakhstanKazakhstan 2015 Soybean imazethapyr 157 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur18205
2 United States (South Carolina) United StatesSouth Carolina1985 Cotton DSMA, and MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur265
3 United States (Alabama) United StatesAlabama1988 Cotton DSMA, and MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur224
4 United States (Mississippi) United StatesMississippi1989 Soybean imazaquin, and imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur251
5 United States (Arkansas) United StatesArkansas1989 Cotton, and Cropland MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur404
6 United States (Tennessee) United StatesTennessee1991 Cotton DSMA, and MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur1104
7 United States (Louisiana) United StatesLouisiana1992 Cotton MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur1045
8 United States (Missouri) United StatesMissouri1992 Soybean chlorimuron-ethyl, and imazaquin 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1080
9 United States (Tennessee) United StatesTennessee1992 Soybean imazaquin 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1105
10 United States (Minnesota) United StatesMinnesota1994 Soybean imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur249
11 United States (Mississippi) United StatesMississippi1994 Cotton DSMA, and MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur254
12 United States (North Carolina) United StatesNorth Carolina1994 Cotton DSMA, and MSMA 45 Nucleic acid inhibitors ( HRAC Group 0 (Legacy Z)
174Xanthium strumariumCommon cocklebur260
13 United States (Arkansas) United StatesArkansas1995 Cropland, and Soybean imazaquin 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur401
14 United States (Iowa) United StatesIowa1995 Soybean chlorimuron-ethyl, and imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1062
15 United States (Oklahoma) United StatesOklahoma1996 Soybean imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1068
16 United States (Kansas) United StatesKansas1997 Soybean chlorimuron-ethyl, and imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1041
17 United States (Maryland) United StatesMaryland1998 Unspecified chlorimuron-ethyl, imazaquin, and imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1086
18 United States (Illinois) United StatesIllinois1998 Corn (maize), and Soybean chlorimuron-ethyl, and imazethapyr 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur7858
19 United States (Ohio) United StatesOhio1999 Soybean chlorimuron-ethyl, and cloransulam-methyl 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur1197
20 United States (North Carolina) United StatesNorth Carolina1999 Soybean chlorimuron-ethyl, cloransulam-methyl, imazapyr, primisulfuron-methyl, and pyrithiobac-sodium 45 Inhibition of Acetolactate Synthase ( HRAC Group 2 (Legacy B)
174Xanthium strumariumCommon cocklebur7820
Literature about Similar Cases

Page size:
select
Page: of 10
Items 1 to 5 of 50

Page size:
select
Page: of 10
Items 1 to 5 of 50

PERMISSION MUST BE OBTAINED FIRST if you intend to base a significant portion of a scientific paper on data derived from this site. Citation:
Heap, I.  The International Herbicide-Resistant Weed Database.  Online.  Thursday, December 2, 2021 .  Available  www.weedscience.org Copyright © 1993- 2021 WeedScience.org All rights reserved. Fair use of this material is encouraged. Proper citation is requested.