International Survey of Herbicide-Resistant Weeds

Countries Weeds Herbicides Mutations Graphs References Researchers
(Polygonum aviculare)

Photosystem II inhibitors (C1/5)

Prostrate Knotweed (Polygonum aviculare) is a dicot weed in the Polygonaceae family.  In Netherlands this weed first evolved resistance to Group C1/5 herbicides in 1987 and infests Corn (maize), and Cropland.   Group C1/5 herbicides are known as Photosystem II inhibitors (Inhibition of photosynthesis at photosystem II).  Research has shown that these particular biotypes are resistant to atrazine and they may be cross-resistant to other Group C1/5 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 NameProstrate Knotweed
SpeciesPolygonum aviculare
GroupPhotosystem II inhibitors (C1/5)
Situation(s)Corn (maize), and Cropland
Contributors - (Alphabetically) 
Edit this Case  |  Add New Case of Resistance  |  Add Note



Homer LeBaron. 1991. Distribution and Seriousness of Herbicide-Resistant Weed Infestations Worldwide. In: Herbicide Resistance in Weeds and Crops. Oorschot, J. L. P. van//Straathof, H. J. M. 1989. On the occurrence and distribution of chlorplastic resistance of weeds to triazines in the Netherlands.

Edit this Note  |  Add New Note


Confirmation Tests

Greenhouse trials comparing a known susceptible Prostrate Knotweed biotype with this Prostrate Knotweed 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 C1/5 resistant Prostrate Knotweed 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

Triazine resistant weeds often exhibit a lower relative fitness when compared to susceptible biotypes.  The most common mutation conferring triazine resistance (Ser 264 to Gly mutation of the psbA gene) also causes a reduction in CO2 fixation, quantum yield, and seed and biomass production.  There is no record in this database referring specifically to fitness studies on Group C1/5 resistant Prostrate Knotweed from Netherlands.
Edit Case  |  Add Note  |  Add Article  |  Add New Case  |  Help



The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Netherlands have been instrumental in providing you this information. 
Herbicide Resistant Prostrate Knotweed Globally
(Polygonum aviculare)
Herbicide Resistant Prostrate Knotweed Globally
(Polygonum aviculare)
Drag a column header and drop it here to group by that column
Herbicide Resistant Prostrate Knotweed Globally
(Polygonum aviculare)
#CountryFirstYearSituationActive IngredientsSite of Action
1 BelgiumBelgium 1984 Apples amitrole 3 Carotenoid biosynthesis (unknown target) (F3/11)
131Polygonum aviculareProstrate Knotweed40
2 NetherlandsNetherlands 1987 Corn (maize), and Cropland atrazine 43 Photosystem II inhibitors (C1/5)
131Polygonum aviculareProstrate Knotweed293
Literature about Similar Cases

Page size:
Page: of 3
Items 1 to 5 of 13

Page size:
Page: of 3
Items 1 to 5 of 13
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.  Saturday, September 26, 2020 .  Available
Copyright © 1993- 2020 All rights reserved. Fair use of this material is encouraged. Proper citation is requested.