International Survey of Herbicide-Resistant Weeds

Countries Weeds Herbicides Mutations Graphs References Researchers
(Amaranthus blitum (ssp. oleraceus))

PSI Electron Diverter (D/22)

Malaysia, Pahang
Livid Amaranth (Amaranthus blitum (ssp. oleraceus)) is a dicot weed in the Amaranthaceae family.  In Malaysia this weed first evolved resistance to Group D/22 herbicides in 1990 and infests Vegetables.   Group D/22 herbicides are known as PSI Electron Diverter (Photosystem-I-electron diversion).  Research has shown that these particular biotypes are resistant to paraquat and they may be cross-resistant to other Group D/22 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 NameLivid Amaranth
SpeciesAmaranthus blitum (ssp. oleraceus)
GroupPSI Electron Diverter (D/22)
LocationMalaysia, Pahang
Contributors - (Alphabetically)Baki Bakar 
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Baki Bakar
Pahang, Perak, Kelantom states.

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Baki Bakar
Paraquat resistance in Solanum nigrum, Crassocephalum crepidiodes, Amaranthus lividus and Conyza sumatrensis in Malaysia. K. Itoh, M. Azmi, and A. Ahmad. In: IWCC Proceedings of the first International Weed Control Congress, Monash University, Melbourne, Australia.

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Confirmation Tests

Field trials comparing a known susceptible Livid Amaranth biotype with this Livid Amaranth 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 D/22 resistant Livid Amaranth 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 D/22 resistant Livid Amaranth from Malaysia please update the database.
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Senior Research Fellow
Institute of Biological Sciences, University Of Malaya
Dept. Of Botany
Faculty of Science Building
Kuala Lumpur, 50603 , Kuala Lumpur
Email Baki Bakar
Web   : Web Site Link


The Herbicide Resistance Action Committee, The Weed Science Society of America, and weed scientists in Malaysia have been instrumental in providing you this information. Particular thanks is given to Baki Bakar for providing detailed information.
Herbicide Resistant Livid Amaranth Globally
(Amaranthus blitum (ssp. oleraceus))
Herbicide Resistant Livid Amaranth Globally
(Amaranthus blitum (ssp. oleraceus))
Drag a column header and drop it here to group by that column
Herbicide Resistant Livid Amaranth Globally
(Amaranthus blitum (ssp. oleraceus))
#CountryFirstYearSituationActive IngredientsSite of Action
1 FranceFrance 1981 Corn (maize) atrazine 17 Photosystem II inhibitors (C1/5)
13Amaranthus blitum (ssp. oleraceus)Livid Amaranth454
2 MalaysiaMalaysia 1990 Vegetables paraquat 28 PSI Electron Diverter (D/22)
13Amaranthus blitum (ssp. oleraceus)Livid Amaranth137
3 SwitzerlandSwitzerland 1978 Grapes simazine 41 Photosystem II inhibitors (C1/5)
13Amaranthus blitum (ssp. oleraceus)Livid Amaranth196
4 United States (New Jersey) United StatesNew Jersey1993 Cabbages, Lettuce, and Onions imazethapyr 45 ALS inhibitors (B/2)
13Amaranthus blitum (ssp. oleraceus)Livid Amaranth1167
Literature about Similar Cases

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Cite this site as: Heap, I.  The International Survey of Herbicide Resistant Weeds.  Online.  Internet.  Tuesday, January 26, 2021 .  Available
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