INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
Marshelder (Iva xanthiifolia) is a dicot weed in the Asteraceae family. In North Dakota this weed first evolved resistance to Group 2 (Legacy B) herbicides in 2003 and infests Soybean. 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 imazamox, and tribenuron-methyl 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.
|Inhibition of Acetolactate Synthase
HRAC Group 2 (Legacy B)
|imazamox, and tribenuron-methyl
|United States, North Dakota
|Contributors - (Alphabetically)
|Greenhouse trials comparing a known susceptible Marshelder biotype with this Marshelder biotype have been used to confirm resistance. For further information on the tests conducted please contact the local weed scientists that provided this information.
|Genetic studies on HRAC Group 2 resistant Marshelder 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
|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.
|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 Marshelder from North Dakota please update the database.
North Dakota State University
Department of Plant Sciences
Loftsgard Hall 470F
Fargo, 58108-6050, North Dakota
Email Kirk Howatt
Web : Web Site Link
|Drag a column header and drop it here to group by that column
|United States (North Dakota)
imazamox, and tribenuron-methyl
Inhibition of Acetolactate Synthase
( HRAC Group 2 (Legacy B)
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.
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