International Survey of Herbicide-Resistant Weeds

Countries Weeds Herbicides Mutations Graphs References Researchers
(Cynodon hirsutus)

EPSP synthase inhibitors (G/9)

Argentina, Córdoba
Gramilla mansa (Cynodon hirsutus) is a monocot weed in the Poaceae family.  In Argentina this weed first evolved resistance to Group G/9 herbicides in 2008 and infests Corn (maize), and Soybean.   Group G/9 herbicides are known as EPSP synthase inhibitors (Inhibition of EPSP synthase).  Research has shown that these particular biotypes are resistant to glyphosate and they may be cross-resistant to other Group G/9 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 Jan 20, 2015 )

Common NameGramilla mansa
SpeciesCynodon hirsutus
GroupEPSP synthase inhibitors (G/9)
LocationArgentina, Córdoba
Situation(s)Corn (maize), and Soybean
Contributors - (Alphabetically)Diego Ustarroz 
Edit this Case  |  Add New Case of Resistance  |  Add Note


Confirmation Tests

Greenhouse trials comparing a known susceptible Gramilla mansa biotype with this Gramilla mansa 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 Group G/9 resistant Gramilla mansa 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 G/9 resistant Gramilla mansa from Argentina please update the database.
Edit Case  |  Add Note  |  Add Article  |  Add New Case  |  Help


Research Associate
Sección Malezas
Ruta 9 Km 636 Manfredi
Córdoba Argentina.
Manfredi, 5688, Córdoba
Email Diego Ustarroz


The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Argentina have been instrumental in providing you this information. Particular thanks is given to Diego Ustarroz for providing detailed information.
Herbicide Resistant Gramilla mansa Globally
(Cynodon hirsutus)
Herbicide Resistant Gramilla mansa Globally
(Cynodon hirsutus)
Drag a column header and drop it here to group by that column
Herbicide Resistant Gramilla mansa Globally
(Cynodon hirsutus)
#CountryFirstYearSituationActive IngredientsSite of Action
1 ArgentinaArgentina 2008 Corn (maize), and Soybean glyphosate 48 EPSP synthase inhibitors (G/9)
276Cynodon hirsutusGramilla mansa5618
Literature about Similar Cases

Page size:
Page: of 0
Items 0 to 0 of 0

Page size:
Page: of 0
Items 0 to 0 of 0
PERMISSION MUST BE OBTAINED FIRST if you intend to base a significant portion of a scientific paper on data derived from this site.
Cite this site as: Heap, I.  The International Survey of Herbicide Resistant Weeds.  Online.  Internet.  Thursday, January 21, 2021 .  Available
Copyright © 1993- 2021 All rights reserved. Fair use of this material is encouraged. Proper citation is requested.