select Select by Site of Action - (Inhibition of dihydroorotate dehydrogenase (DHODH) ) A (Inhibition of Acetyl CoA Carboxylase ) B (Inhibition of Acetolactate Synthase ) C1 (PSII inhibitors - Serine 264 Binders ) C1 C2 (PSII inhibitors - Serine 264 Binders ) C3 (PSII inhibitors - Histidine 215 Binders ) D (PS I Electron Diversion ) E (Inhibition of Protoporphyrinogen Oxidase ) F1 (Phytoene Desaturase inhibitors) F2 (Inhibition of Hydroxyphenyl Pyruvate Dioxygenase ) F3 (Inhibition of Lycopene Cyclase ) F4 (Inhibition of Deoxy-D-Xylulose Phosphate Synthase) G (Inhibition of Enolpyruvyl Shikimate Phosphate Synthase ) H (Inhibition of Glutamine Synthetase ) I (Inhibition of Dihydropteroate Synthase) K1 (Inhibition of Microtubule Assembly) K2 (Inhibition of Microtubule Organization ) K3 N (Very Long-Chain Fatty Acid Synthesis inhibitors) L (Inhibition of Cellulose Synthesis ) M (Uncouplers) N (Inhibition of Very Long-Chain Fatty Acid Synthesis ) O (Auxin Mimics ) P (Auxin Transport inhibitor) Q (Inhibition of Fatty Acid Thioesterase ) R (Inhibition of Serine-Threonine Protein Phosphatase ) S (Inhibition of Solanesyl Diphosphate Synthase ) T (Inhibition of Homogentisate Solanesyltransferase ) Z (Antimicrotubule mitotic disrupter) Z (Cell elongation inhibitors) Z (Nucleic acid inhibitors) Z (Unknown)

Weeds Resistant to Unknown (Z/27) by species and country
Weeds Resistant to Unknown (Z/27) by species and country Drag a column header and drop it here to group by that column

Weeds Resistant to Unknown (Z/27) by species and country

#	Species	Country	First Year	WeedID	Species	CommonName	HRAC	MOAID	WSSA	HerbicideGroup
1	Nassella neesiana Chilean or Uruguayan Needlegrass	1992 - New Zealand	1992	169	Nassella neesiana	Chilean or Uruguayan Needlegrass	Z	29	27	Unknown
2	Nassella trichotoma Serrated Tussock	2002 - Australia (Victoria)	2002	221	Nassella trichotoma	Serrated Tussock	Z	29	27	Unknown
3	Poa annua Annual Bluegrass	2009 - Australia (Victoria) 2017 - Australia (New South Wales ) 2017 - Australia (New South Wales ) *Multiple - 5 SOA's 2017 - Australia (South Australia)	2009	130	Poa annua	Annual Bluegrass	Z	29	27	Unknown
4	Sporobolus fertilis Giant Parramatta grass	2004 - Australia (New South Wales )	2004	325	Sporobolus fertilis	Giant Parramatta grass	Z	29	27	Unknown

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Cite this site as: Heap, I.  The International Survey of Herbicide Resistant Weeds.  Online.  Internet.  Monday, November 3, 2025 .  Available  www.weedscience.org
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