MODE OF ACTION
CLASSIFICATION SCHEME
VERSION 11.1, JANUARY 2024

PREPARED IRAC International MoA Working GroupAPPROVED IRAC Executive

DISCLAIMER
The technical information contained in this publication is provided to you for yourreference. While CropLife International and the RACs make every effort topresent accurate and reliable information in the guidelines, CropLife International
and the RACs do not guarantee the accuracy, completeness, efficacy, timeliness, orcorrect sequencing of such information. Inclusion of active ingredients andproducts on the RAC Code Lists is based on scientific evaluation of their modes ofaction; it does not provide any kind of testimonial for the use of a product or a
judgment on efficacy. CropLife International and the RACs are not responsible for,and expressly disclaim all liability for, damages of any kind arising out of use,
reference to, or reliance on information provided in the guidelines. Listing ofchemical classes or modes of action in any of the CropLife International/RAC
recommendations must not be interpreted as approval for use of a compound in agiven country. Prior to implementation, each user must determine the current
registration status in the country of use and strictly adhere to the uses andinstructions approved in that country.

IRAC document protected by © Copyright 2024

Mode of Action Classification v11.1

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Table of Contents
1.

Scope …………………………………………………………….……………………………………………………………...….……….4

2.

Purpose ………………………………………………………………………………………………………………..……….…………..4

3.

What is resistance?.........................................................................................................................................................44.

MoA, Target-site resistance and Cross-resistance ...……………………………………………………………….4

5.

Use of alternations or sequences of different MoAs ……………….……………………………………….…......5

6.

Non-target site resistance mechanisms ……………………………………………….………………………………….5

7.

The MoA Classification Scheme ………………………………………………………………………………….………..….6
7.1 Rules for inclusion of an insecticidal agent in the MoA list ………………………………………………6
7.2 The Classification Table ……………………………………………………………………………………….………..….7
7.3 Criteria for descriptors of the quality of MoA information ………………………………………...….18
7.4 Notes regarding sub-groups ……………………………………………………………………………………..….…18
7.5 General notes & MoA Classification Scheme Updates……………………………………..……….……19

Appendix 1
Product labels: Indication of MoA of active ingredient and accompanying IRM advice…………….……21

Appendix 2
IRM principles recommended and endorsed by IRAC …………………………………………………………………….24

Appendix 3
MoA group descriptors……..……….………………………………………...………………………………………………………..…25

Appendix 4
Procedure for allocation of new insecticidal materials to the MoA Classification …………………….…..30

Appendix 5
Active Ingredients in alphabetical order with their MOA Classification .......................................................35

Appendix 6
Active ingredients pending registration…………………………….………………………………………………...…….……..43

Mode of Action Classification v11.1

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1. Scope
The IRAC classification is intended to cover all materials, chemical, biological or other, that are used tocontrol insects or acarines on crops, in structures or in the environment. Some insecticides and acaricides
also control nematodes, but selective nematicides are covered in a separate Nematicide MoA
classification document available at https://www.irac-online.org/. Behaviour-modifying agents andpredatory insects/mites are not included. Products used only by direct application to animals or humans
for control of parasites are likewise not included.
Note: Inclusion in the MoA list does not necessarily signify regulatory approval.

2. Purpose
The IRAC Mode of Action (MoA) classification provides growers, advisors, extension staff, consultants
and crop protection professionals with a guide to the selection of acaricides or insecticides for use in an
effective and sustainable acaricide or insecticide resistance management (IRM) strategy. In addition topresenting the MoA classification, this document outlines the background to, and purposes of, theclassification list, and provides guidance on how it is used for IRM purposes. Many countries now require
the IRAC MoA group code included on labels and this is recommended even if not required. Labelingguidelines are given in Appendix 1 and require that the active ingredient be listed in Appendix 5.
Procedures for requesting IRAC classification of a new/unlisted active ingredient are found in Appendix
4. This document is reviewed and re-issued as needed.

3. What is resistance?
Resistance to insecticides may be defined as ‘a heritable change in the sensitivity of a pest population thatis reflected in the repeated failure of a product to achieve the expected level of control when usedaccording to the label recommendation for that pest species’ (IRAC). This definition differs slightly fromothers in the literature, but IRAC believes it represents the most accurate practical definition of relevanceto growers. Resistance arises through the over-use or misuse of an insecticide or acaricide against a pest
species and results from the Darwinian selection of resistant forms of the pest and the consequentevolution of populations that are resistant to that insecticide or acaricide.

4. MoA, Target-site resistance and Cross-resistanceIn many cases, not only does resistance render the selecting insecticidal or acaricidal agent ineffective, but it
also confers cross-resistance to other structurally related agents. This is because agents with structural

Mode of Action Classification v11.1

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similarity usually share a common target site within the pest, and thus share a common MoA. It is common forresistance to develop that is based on a genetic modification of this target site. When this happens, theinteraction of the selecting insecticidal or acaricidal agent with its target site is impaired and the agent loses its
pesticidal efficacy. Because all insecticidal and acaricidal agents with structural similarity share a common
MoA, there is a high risk that existing or developing target-site resistance will confer cross-resistance to allagents in the same group. It is this concept of cross-resistance within a family of structurally related
insecticides or acaricides that is the basis of the IRAC MoA classification.

5. Use of alternations or sequences of different MoAs
The objective of successful Insecticide Resistance Management (IRM) is to prevent or delay the evolution ofresistance to insecticides, or to help regain susceptibility in insect pest populations in which resistance has
already arisen. Effective IRM is thus an important element in maintaining the efficacy of valuable insecticides.
It is important to recognize that it is usually easier to proactively prevent resistance from occurring than it is toreactively regain susceptibility. Nevertheless, the IRAC MoA classification will always provide valuableguidance to the design of effective IRM strategies.
Experience has shown that all effective insecticide or acaricide resistance management strategies seek tominimise the selection for resistance from any one type of insecticide or acaricide. In practice, alternations,sequences or rotations of insecticidal or acaricidal agents from different MoA groups provide a sustainable andeffective approach to IRM. This ensures that selection from insecticidal agents in any one MoA group is
minimised. The IRAC classification in this document is provided as an aid to insecticide selection for thesetypes of IRM strategies. Applications are often arranged into MoA spray windows or blocks that are defined by
the stage of crop development and the biology of the pest(s) of concern. Local expert advice should always befollowed regarding spray windows and timings. Several sprays of an insecticidal agent may be possible withineach spray window, but successive generations of a pest should not be treated with insecticidal agents fromthe same MoA group.
Groups in the classification whose members do not act at a common target site are exempt from theproscription against rotation within the group. These are Group 8, Miscellaneous non-specific (multi-site)
inhibitors; Group 13, Uncouplers of oxidative phosphorylation via disruption of the proton gradient; and all theUN groups: UN, UNB, UNE, UNF, UNM, UNP and UNV.

To help delay resistance, it is strongly recommended that growers also integrate other control methods
into insect or mite control programmes. Further advice is given in Appendix 2.

6. Non-target-site resistance mechanisms
It is fully recognized that resistance of insects and mites to insecticides and acaricides can, and frequently
does, result from enhanced metabolism by enzymes within the pest. Such metabolic resistancemechanisms are not linked to any specific site of action classification and therefore they may confer

Mode of Action Classification v11.1

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resistance to insecticides in more than one IRAC MoA group. Where such metabolic resistance has beencharacterized and the cross-resistance spectrum is known, it is possible that certain alternations,sequences or rotations of MoA groups cannot be used. Similarly, mechanisms of reduced penetration of
the pesticide into the pest, or behavioural changes of the pest may also confer resistance to multiple MoA
groups. Where such mechanisms are known to give cross-resistance between MoA groups, the use of
insecticides should be modified appropriately.
Where the resistance mechanism(s) is unknown, the intelligent use of alternations, sequences orrotations of insecticidal agents from different MoA classes remains an entirely viable resistancemanagement technique, since such a practice will always minimise selection pressures.

7. The MoA Classification Scheme
The IRAC MOA classification scheme is based on the best available evidence of the MoA of available
insecticidal and acaricidal agents. Details of the classification have been agreed upon by IRAC member
companies and approved by internationally recognized industrial and academic insect toxicologists andbiochemists.
Insecticidal and acaricidal agents are classified into two types of MoA groups: numbered groups whose
members are known or thought to act at specific target sites, and UN groups of undefined or unknown
mode of action. The only exceptions are the numbered groups 8, Miscellaneous non-specific (multi-site)
inhibitors and 13, Uncouplers of oxidative phosphorylation via disruption of the proton gradient, which
for historical reasons retain their legacy group numbers even though they are not acting at specific target
sites. Nevertheless, it is the intention of the IRAC MoA working group going forward to only assign group
numbers where there is good evidence of a common target site.
Insecticidal compounds, bacterial agents, extracts and crude oils, fungal agents, mechanical disruptors,
peptides and viruses of unknown Mode of Action are classified in groups UN, UNB, UNE, UNF, UNM,
UNP and UNV, respectively.

7.1 Rules for inclusion of an insecticidal agent in the MoA list•

Chemical nomenclature is generally based on ISO accepted common names.

•

To be included in the active list, insecticidal agents must have a minimum of one registered use in
at least one country.

•

In any one MoA classification sub-group, where more than one active ingredient in that sub-groupis registered for use, the sub-group name is used.

•

In any one MoA classification sub-group, where only one active ingredient is registered for use,
the name of that exemplifying active ingredient may be used

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7.2 The Classification Table
IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

Sub-group, classor exemplifying
Active Ingredient

1

1A
Carbamates

Alanycarb, Aldicarb, Bendiocarb, Benfuracarb,
Butocarboxim, Butoxycarboxim, Carbaryl,
Carbofuran, Carbosulfan, Ethiofencarb,
Fenobucarb, Formetanate, Furathiocarb,
Isoprocarb, Methiocarb, Methomyl, Metolcarb,
Oxamyl, Pirimicarb, Propoxur, Thiodicarb,
Thiofanox, Triazamate,Trimethacarb, XMC,
Xylylcarb

1B
Organophosphates

Acephate, Azamethiphos, Azinphos-ethyl,
Azinphos-methyl, Cadusafos, Chlorethoxyfos,
Chlorfenvinphos, Chlormephos, Chlorpyrifos,
Chlorpyrifos-methyl, Coumaphos, Cyanophos,
Demeton-S-methyl, Diazinon, Dichlorvos/ DDVP,
Dicrotophos, Dimethoate, Dimethylvinphos,
Disulfoton, EPN, Ethion, Ethoprophos, Famphur,
Fenamiphos, Fenitrothion, Fenthion,
Fosthiazate, Heptenophos, Imicyafos,
Isofenphos, Isopropyl O-(methoxyaminothiophosphoryl) salicylate, Isoxathion, Malathion,
Mecarbam, Methamidophos, Methidathion,
Mevinphos, Monocrotophos, Naled, Omethoate,
Oxydemeton-methyl, Parathion, Parathionmethyl, Phenthoate, Phorate, Phosalone,
Phosmet, Phosphamidon, Phoxim, Pirimiphosmethyl, Profenofos, Propetamphos, Prothiofos,
Pyraclofos, Pyridaphenthion, Quinalphos,
Sulfotep, Tebupirimfos, Temephos, Terbufos,
Tetrachlorvinphos, Thiometon, Triazophos,
Trichlorfon, Vamidothion

Acetylcholinesterase (AChE)
inhibitors
Nerve action{Strong evidence that action at
this protein is responsible for
insecticidal effects}

2
GABA-gated chloride channel
blockers
Nerve action{Strong evidence that action at
this protein is responsible for
insecticidal effects}

Active Ingredients

2A
Cyclodiene
Organochlorines

Chlordane, Endosulfan

2B
Phenylpyrazoles(Fiproles)

Ethiprole, Fipronil

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

Sub-group, classor exemplifying
Active Ingredient3

3A
Pyrethroids
Pyrethrins

Sodium channel modulators
Nerve action{Strong evidence that action at
this protein is responsible for
insecticidal effects}

3B
DDT
Methoxychlor4
Nicotinic acetylcholine
receptor (nAChR) competitive
modulators

4A
Neonicotinoids

Active Ingredients

Acrinathrin, Allethrin, d-cis-trans Allethrin, dtrans Allethrin, Bifenthrin, Bioallethrin,
Bioallethrin S-cyclopentenyl isomer ,Bioresmethrin, Cycloprothrin, Cyfluthrin, betaCyfluthrin, Cyhalothrin, lambda-Cyhalothrin,
gamma-Cyhalothrin, Cypermethrin, alphaCypermethrin, beta-Cypermethrin, thetacypermethrin, zeta-Cypermethrin, Cyphenothrin ,(1R)-trans- isomers], Deltamethrin, Empenthrin(EZ)- (1R)- isomers], Esfenvalerate, Etofenprox,
Fenpropathrin, Fenvalerate, Flucythrinate,
Flumethrin, tau-Fluvalinate, Halfenprox,
Imiprothrin, Kadethrin, Permethrin, Phenothrin[(1R)-trans- isomer], Prallethrin, Pyrethrins(pyrethrum), Resmethrin, Silafluofen, Tefluthrin,
Tetramethrin, Tetramethrin [(1R)-isomers],
Tralomethrin, Transfluthrin,

DDT
Methoxychlor
Acetamiprid, Clothianidin, Dinotefuran,
Imidacloprid, Nitenpyram, Thiacloprid,
Thiamethoxam,

Nerve action

4B
Nicotine

Nicotine{Strong evidence that action at
one or more of this class ofprotein is responsible for
insecticidal effects}

4C
Sulfoximines

Sulfoxaflor

4D
Butenolides

Flupyradifurone

4E
Mesoionics

Dicloromezotiaz, Fenmezoditiaz,
Triflumezopyrim

4F
Pyridylidenes

Flupyrimin

Spinosyns

Spinetoram, Spinosad

5
Nicotinic acetylcholine
receptor (nAChR) allostericmodulators – Site I
Nerve action{Strong evidence that action at
one or more of this class ofprotein is responsible for
insecticidal effects}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

6
Glutamate-gated chloride
channel (GluCl) allostericmodulators

Avermectins,
Milbemycins

Abamectin, Emamectin benzoate, Lepimectin,
Milbemectin

7A
Juvenile hormone
analogues

Hydroprene, Kinoprene, Methoprene

Nerve and muscle action{Strong evidence that action at
one or more of this class ofprotein is responsible for
insecticidal effects}

7
Juvenile hormone receptor
modulators
Growth regulation{Strong evidence that action at
one or more of this class ofprotein is responsible for
insecticidal effects}

8*
Miscellaneous non-specific(multi-site) inhibitors

7B
Fenoxycarb

Fenoxycarb

7C
Pyriproxyfen

Pyriproxyfen

8A
Alkyl halides
8B
Chloropicrin
8C
Fluorides
8D
Borates
8E
Tartar emetic

9
Chordotonal organ TRPV
channel modulators
Nerve action{Strong evidence that action at
one or more of this class ofproteins is responsible for
insecticidal effects}

1,3-dichloropropene, Methyl bromide and otheralkyl halides
Chloropicrin
Cryolite (Sodium aluminum fluoride), Sulfuryl
fluoride
Borax, Boric acid, Disodium octaborate, Sodium
borate, Sodium metaborate
Tartar emetic

8F
Methyl isothiocyanate
generators

Dazomet, Metam, Methyl isothiocyanate

9B
Pyridine azomethinederivatives

Pymetrozine, Pyrifluquinazon

9D
Pyropenes

Afidopyropen

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

Sub-group, classor exemplifying
Active Ingredient

10

10A
Clofentezine
Diflovidazin
Hexythiazox

Mite growth inhibitors
affecting CHS1
Growth regulation{Strong evidence that action at
one or more of this class ofproteins is responsible for
insecticidal effects}

11
Microbial disruptors of insect
midgut membranes(Includes transgenic crops
expressing Bacillus thuringiensis
toxins, however specificguidance for resistancemanagement of transgenic
crops is not based on rotation ofmodes of action)

12
Inhibitors of mitochondrial
ATP synthase
Energy metabolism{Compounds affect the functionof this protein, but it is not clearthat this is what leads tobiological activity}

13 *Uncouplers of oxidative
phosphorylation via
disruption of the proton
gradient
Energy metabolism

10B
Etoxazole

11A
Bacillus thuringiensis
and the insecticidal
proteins they produce

Active Ingredients

Clofentezine, Diflovidazin, Hexythiazox

Etoxazole

Bacillus thuringiensis subsp. israelensis
Bacillus thuringiensis subsp. aizawai
Bacillus thuringiensis subsp. kurstaki
Bacillus thuringiensis subsp. tenebrionis
B.t. crop proteins: (* Please see footnote)
Cry1Ab, Cry1Ac, Cry1Fa, Cry1A.105, Cry2Ab,
Vip3A, mCry3A, Cry3Ab, Cry3Bb,
Cry34Ab1/Cry35Ab1

11B
Bacillus sphaericus

Bacillus sphaericus

12A
Diafenthiuron

Diafenthiuron

12B
Organotin miticides

Azocyclotin, Cyhexatin, Fenbutatin oxide

12C
Propargite

Propargite

12D
Tetradifon

Tetradifon

Pyrroles

Chlorfenapyr

Dinitrophenols

DNOC

Sulfluramid

Sulfluramid

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

14
Nicotinic acetylcholine
receptor (nAChR) channel
blockers

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

Nereistoxin analogues

Bensultap, Cartap hydrochloride, Thiocyclam,
Thiosultap-sodium

Benzoylureas

Bistrifluron, Chlorfluazuron, Diflubenzuron,
Flucycloxuron, Flufenoxuron, Hexaflumuron,
Lufenuron, Novaluron, Noviflumuron,
Teflubenzuron, Triflumuron

Buprofezin

Buprofezin

Cyromazine

Cyromazine

Diacylhydrazines

Chromafenozide, Halofenozide,
Methoxyfenozide, Tebufenozide

Nerve action{Compounds affect the functionof this protein, but it is not clearthat this is what leads tobiological activity}

15
Inhibitors of chitinbiosynthesis affecting CHS1
Growth regulation{Strong evidence that action at
one or more of this class ofproteins is responsible for
insecticidal effects}

16
Inhibitors of chitinbiosynthesis, type 1
Growth regulation{Target protein responsible forbiological activity is unknown, or
uncharacterized}

17
Moulting disruptors, DipteranGrowth regulation{Target protein responsible forbiological activity is unknown, or
uncharacterized}

18
Ecdysone receptor agonists
Growth regulation{Strong evidence that action at
this protein is responsible for
insecticidal effects}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

19

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

Amitraz

Amitraz

20A
Hydramethylnon

Hydramethylnon

Energy metabolism

20B
Acequinocyl

Acequinocyl{Good evidence that action at
this protein complex is
responsible for insecticidal
effects}

20C
Fluacrypyrim

Fluacrypyrim

20D
Bifenazate

Bifenazate

21A
METI acaricides andinsecticides

Fenazaquin, Fenpyroximate, Pyridaben,
Pyrimidifen, Tebufenpyrad, Tolfenpyrad{Good evidence that action at
this protein complex is
responsible for insecticidal
effects}

21B
Rotenone

Rotenone (Derris)

22

22A
Oxadiazines

Indoxacarb

22B
Semicarbazones

Metaflumizone

Octopamine receptor agonists
Nerve action{Good evidence that action at
one or more of this class ofprotein is responsible for
insecticidal effects}

20
Mitochondrial complex III
electron transport inhibitors –Qo site21
Mitochondrial complex I
electron transport inhibitors
Energy metabolism

Voltage-dependent sodium
channel blockers
Nerve action{Good evidence that action at
this protein complex is
responsible for insecticidal
effects}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

23
Inhibitors of acetyl-CoA
carboxylase

Tetronic and Tetramic
acid derivatives

Spidoxamat Spirodiclofen, Spiromesifen,
Spiropidion, Spirotetramat

Lipid synthesis, growth
regulation{Good evidence that action at
this protein is responsible for
insecticidal effects}

24
Mitochondrial complex IVelectron transport inhibitors
Energy metabolism{Good evidence that action at
this protein complex is
responsible for insecticidal
effects}25
Mitochondrial complex IIelectron transport inhibitors
Energy metabolism{Good evidence that action at
this protein complex is
responsible for insecticidal
effects}

28
Ryanodine receptor
modulators

24A
Phosphides

24B
CyanidesAluminium phosphide, Calcium phosphide,
Phosphine, Zinc phosphide

Calcium cyanide, Potassium cyanide, Sodium
cyanide25A
Beta-ketonitrile
derivatives

Cyenopyrafen, Cyflumetofen

25B
Carboxanilides

Pyflubumide

DiamidesChlorantraniliprole, Cyantraniliprole,
Cyclaniliprole Flubendiamide, Tetraniliprole

Nerve and muscle action{Strong evidence that action at
this protein complex is
responsible for insecticidal
effects}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

29
Chordotonal organ
nicotinamidase inhibitors

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

Flonicamid

Flonicamid

Meta-diamides
Isoxazolines

Broflanilide
Fluxametamide, Isocyloseram

Granuloviruses (GVs)

Cydia pomonella GV
Thaumatotibia leucotreta GV

Nucleopolyhedroviruses (NPVs)

Anticarsia gemmatalis MNPV
Helicoverpa armigera NPV

GS-omega/kappa
HXTX-Hv1a peptide

GS-omega/kappa HXTX-Hv1a peptide

Nerve action{Strong evidence that action at
this protein is responsible for
insecticidal effects}

30
GABA-gated chloride channel
allosteric modulators
Nerve action{Strong evidence that action at
this protein complex is
responsible for insecticidal
effects}

31
Baculoviruses
Host-specific occluded
pathogenic viruses{Midgut epithelial columnar cell
membrane target site –undefined}

32
Nicotinic Acetylcholine
Receptor (nAChR) Allosteric
Modulators - Site II
Nerve action{Strong evidence that action at
one or more of this class ofprotein is responsible for
insecticidal effects}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

33

Calcium-activated potassiumchannel (KCa2) modulators

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

Acynonapyr

Acynonapyr

Flometoquin

Flometoquin

Ledprona

Ledprona

Pyridazine
pyrazolecarboxamides

Dimpropyridaz

Azadirachtin

Azadirachtin

Benzoximate

Benzoximate

Benzpyrimoxan

Benzpyrimoxan

Bromopropylate

Bromopropylate

Chinomethionat

Chinomethionat

Nerve action{Strong evidence that action at
this protein is responsible for
insecticidal effects}

34
Mitochondrial complex III
electron transport inhibitors –Qi siteEnergy metabolism{Modulation of this protein
complex has been clearly
demonstrated and the specifictarget site responsible forbiological activity is distinct fromGroup 20}35
RNA Interference mediatedtarget suppressors
Activation of the RNAimechanism which specificallyreduces abundance of the target
messenger RNA (mRNA)
resulting in the reduction of theprotein encoded by the mRNA.

36
Chordotonal organ
modulators – undefined target
site
Nerve action{Modulation of chordotonalorgan function has been clearly
demonstrated, but the specifictarget protein(s) responsible forbiological activity are distinct
from Group 9 and Group 29 andremain undefined}UN*
Compounds of unknown or
uncertain MoA{Target protein responsible forbiological activity is unknown, or
uncharacterized}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

UNB*
Bacterial agents (non-Bt) of
unknown or uncertain MoA

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

DicofolDicofol

Lime sulfur

Lime sulfur

Mancozeb

MancozebOxazosulfyl

Oxazosulfyl

Pyridalyl

PyridalylSulfurSulfurBurkholderia spp
Wolbachia pipientis (Zap){Target protein responsible forbiological activity is unknown or
uncharacterized}

UNE*
Botanical essence including
synthetic, extracts andunrefined oils with unknown
or uncertain MoA{Target protein responsible forbiological activity is unknown, or
uncharacterized}

UNF*
Fungal agents of unknown or
uncertain MoA{Target protein responsible forbiological activity is unknown, or
uncharacterized}

UNM*
Non-specific mechanical andphysical disruptors

Chenopodium ambrosioides near ambrosioides
extract
Fatty acid monoesters with glycerol orpropanediol Neem oil

Akanthomyces muscarius Ve6
Beauveria bassiana strains
Metarhizium brunneum strain F52
Paecilomyces fumosoroseus Apopka strain 97

Diatomaceous earth
Mineral oil{Target protein responsible forbiological activity is unknown, or
uncharacterized}

UNP*
Peptides of unknown or
uncertain MoA{Target protein responsible forbiological activity is unknown, or
uncharacterized}

Mode of Action Classification v11.1

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IRAC MoA Classification Version 11.1, January 2024
See section 7.4 for further information on sub-groups.
See section 7.3 for criteria for descriptors of the quality of MoA information.
Main Group and Primary Siteof Action

Sub-group, classor exemplifying
Active Ingredient

Active Ingredients

UNV*
Viral agents (non-baculovirus)of unknown or uncertain MoA{Target protein responsible forbiological activity is unknown, or
uncharacterized}

Table Notes:a) The color scheme used associates modes of action into broad categories based on thephysiological functions affected, as an aid to understanding symptomology, speed of action andother properties of the insecticides, and not for any resistance management purpose. Rotations
for resistance management should be based only on the numbered mode of action groups.
b) Inclusion of an insecticidal agent in the classification above does not necessarily signify
regulatory approval.
c) MoA assignments will usually involve identification of the target protein responsible for the
biological effect, although groupings can be made where insecticidal agents share distinctive
physiological effects and are structurally related.
d) Groups 26 and 27 are unassigned at this time and have therefore been omitted from the table.
e) An insecticidal agent with an unknown or controversial MoA or an unknown mode of toxicity will
be held in group ‘UN’ or ‘UNB’, ‘UNE’, ‘UNF’, ‘UNM’, ‘UNP’, UNV as applicable until evidence
becomes available to enable assignment to a more appropriate MoA class.
f) Actives in groups marked with an asterisk are thought not to share a common target site andtherefore may be freely rotated with each other unless there is reason to expect crossresistance. These groups are 8, 13, UN, UNB, UNE, UNF, UNM, UNP and UNV.
g) Different baculoviruses that target different insect orders may be used together withoutcompromising their resistance management. Rotation between certain specific baculoviruses
may provide resistance management benefits for some pests. Consult product-specificrecommendations.
h) While there is strong evidence that Bifenazate acts on the Qo site of Mitochondrial Complex III
and some Bifenazate resistance mutations confer cross-resistance to acequinocyl, the sites ofaction of Fluacrypyrim and Hydramethylnon have not been determined.
i) Because of documented cross-resistance between dicofol, bromopropylate and abamectin,
these active ingredients should not be rotated after each other in an IRM program.

Mode of Action Classification v11.1

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7.3. Criteria for descriptors of the quality of MoA information{Strong evidence that action at thisprotein (or protein complex) is
responsible for insecticidal effects}

Potent effects on the function of the target protein andeither resistance due to mutation / overexpression /removal of this protein or correlation of potency
between effects on the protein and biological activity fora set of related insecticidal agents.

{Good evidence that action at thisprotein (or protein complex) is
responsible for insecticidal effects}{Insecticidal agents affect thefunction of this protein, but it is notclear that this is what leads tobiological activity}

Highly potent effects on the function of the protein
combined with clearly consistent physiological effects{Target protein responsible forbiological activity is unknown, or
uncharacterized}

Insecticidal agents may be grouped because of similarityof structure and distinctive physiological effect.

Insecticidal agents (or their active principles) havemoderate or low potency on the function of the protein,
and there is little or no evidence associating this effectwith biological activity. Insecticidal agents may begrouped because of similarity of structure and distinctive
physiological effect.

7.4. Notes regarding sub-groups
Sub-groups represent distinct classes of insecticidal agents that are believed to have the same MoA but are
different enough in structure or mode of interaction with the target protein that the chance of selection for
either metabolic or target-site cross-resistance is reduced compared to closely related insecticidal agents.
Sub-groups may also distinguish insecticidal agents that are structurally similar but known to binddifferently within the target or to have differential selectivity among multiple targets. Evidence supportinglack of cross-resistance between existing compounds within the Group and the new active ingredientsubmission must be provided to support sub-grouping. This should include bioassay-based studies andprovide quantifiable resistance ratios between susceptible and resistant strains.
The cross-resistance potential between sub-groups is higher than that between different groups, sorotation between sub-groups should be avoided. In exceptional circumstances (i.e. where effective
registered insecticides from other mode of action groups are unavailable) rotation may be consideredfollowing consultation with local expert advice and where cross-resistance does not exist. These exceptions
should not be considered sustainable resistance management strategies, and alternative options should besought to maintain pest susceptibility.

Mode of Action Classification v11.1

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The following notes provide additional information about particular sub-groups.
Sub-groups

Notes

3A & 3B

Because DDT is no longer used in agriculture, this is only applicable for thecontrol of insect vectors of human disease such as mosquitoes.
Although these compounds are believed to have the same target site, current
evidence indicates that the risk of metabolic cross-resistance between
subgroups is low.
Hexythiazox is grouped with clofentezine because they exhibit cross-resistance,even though they are structurally distinct. Diflovidazin has been added to thisgroup because it is a close analogue of clofentezine and is expected to have thesame mode of action.

4A, 4B, 4C,
4D, 4E & 4F
10A

11A

22A & 22B

25A & 25B

Different Bacillus thuringiensis products that target different insect orders may
be used together without compromising their resistance management. Rotation
between certain specific Bacillus thuringiensis microbial products may provide
resistance management benefits for some pests. Consult product-specificrecommendations.
B.t. Crop Proteins: Where there are differences among the specific receptors
within the midguts of target insects, transgenic crops containing certain
combinations of the listed proteins provide resistance management benefits.
Although these compounds are believed to have the same target site, current
evidence indicates that the risk of metabolic cross-resistance between
subgroups is low.
Although these compounds are believed to have the same target site, current
evidence indicates that the risk of metabolic cross-resistance between
subgroups is low.

7.5. General notes & MoA Classification Scheme updates•

Further details on the MoA Group Descriptors are given in Appendix 3.

•

A list of active ingredients in alphabetical order with their respective MoA classification is given in
Appendix 5.

•

The Classification Scheme has been prepared using the most up-to-date information available toIRAC. It is provided to user groups, grower organisations, extension personnel, regulatory
authorities such as the US EPA and all those involved in resistance management, as an agreed
definitive statement by the plant protection industry on the MoA of insecticides currently in use.

•

The IRAC MoA classification is reviewed and reissued at intervals as required. The latest version
is always available for reference via the IRAC website (www.irac-online.org).

•

Submissions for new active ingredients together with recommendations for their inclusion in
specific new or existing MoA classes, together with citations or evidence for classification should
be made to IRAC through the website.

•

IRAC member companies review draft versions before an agreed final version of any update is
published. In addition, several internationally well-known insect toxicologists and biochemists canMode of Action Classification v11.1

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be consulted regarding additions, deletions or other changes to the list. Details of the procedures
followed for allocation of new insecticidal materials to the MoA classification are given in
Appendix 4.
•

Changes to the listing may have serious consequences. In those countries where insecticide labels
display the IRAC MoA number or class name as an aid to good IRM (see Appendix 1), changes may
be especially costly to implement. In general, changes are therefore only endorsed when thescientific evidence supporting the change is compelling.

•

Superseded, obsolete or withdrawn insecticidal agents for which no current registration exists, andthat are no longer in common usage, are not listed.

•

In a continued effort to refine the list, readers are kindly asked to inform IRAC of factual errors oromissions, citing definitive evidence wherever possible. Such submissions should be directed to
IRAC via the website. Suggestions for improvements are likewise welcome.

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Appendix 1
Product labels: Indication of MoA of active ingredient andaccompanying IRM advice
To assist users in the selection of insecticides for use in IRM strategies employing sequences, rotations oralternations of MoA groups, IRAC is encouraging producers to clearly indicate the IRAC MoA group
number and description on the product label, and to accompany this with appropriate advice of the typeindicated below. Thus, in addition to the detailed product information, handling, and safety information
required by local regulations, a typical label should clearly indicate the IRAC MoA Group number &description, and minimal, brief advice on IRM as indicated in the example below.
Inclusion of the IRAC group on the label is a warrant from the manufacturer that the insecticide has beenclassified by IRAC and is listed in Appendix 5 of this document, the only authoritative and comprehensive
list of IRAC-classified insecticides. If an insecticide is not listed in Appendix 5 and falls within the scope of
the IRAC classification as stated at the beginning of this document, please petition IRAC for classificationof the product, as directed in Appendix 4, before drafting a label. Insecticidal materials falling outside thescope of the classification may be labeled as “Exempt from IRAC Classification”.
For resistance management purposes,
Product XXX insecticide is an IRAC MoAGroup 15 insecticide. Any insect population
may contain individuals naturally resistantto Product XXX and other Group 15
insecticides. If these insecticides are used
repeatedly, the resistant individuals may
eventually dominate the pest insect
population. These resistant insects may not
be controlled by Product XXX insecticide orby other Group 15 insecticides. To delay
the development of resistance:• Avoid exclusive repeated use of
insecticides from the same chemical subgroup, (indicated by the IRAC MoA Group
number).
• Alternate with products from other
IRAC MoA Groups• Integrate other control methods(chemical, cultural, biological) into insect
control programs.

For further information on resistance management and advice on IRM programmes contact your local
distributor.

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LABELLING SPECIFICS
It is recommended that the MoA icon is displayed in a prominent position on the label. A position at the
top right of the front panel of the label is strongly recommended as shown in the example above. A clearly
defined font should be used, e.g., Arial or Calibri for users of Latin script. A black and white colour scheme
is recommended. The icon uses the word GROUP in capital letters in black font on a white background;the mode of action letter or numeral should be in white font on a black background; the word
INSECTICIDE in capital letters in black font on a white background. Both lines, and the whole indicator,
are contained within black rectangles. See example below.

The words GROUP and INSECTICIDE in capital letters which should not be less than one-quarter of theheight of the largest letter or numeral on the label and be between 2 mm and 12.5 mm high. If more than
one insecticide is included in a product then the icon should be written in plural e.g. INSECTICIDES not
INSECTICIDE. The appropriate letter(s) or number(s) representing the Mode of Action (MoA) group(s) ofeach active constituent(s) are to be inserted between the words GROUP and INSECTICIDE. The width of
the white line that separates the groups for the pesticides in a product with more than one active
ingredient should be defined. It should be wide enough so that when the icon is printed on small packets
the line is clear. The letter(s) representing the mode of action should be written in capital letters whichshould not be less than one-half the height of the largest letter or numeral on the label and between 4 mm
and 25 mm high. The words GROUP and INSECTICIDE must be no less than half, and no more than theactual size of the group number or letter.
Note that where a product has two or more active constituents, and these are represented by two or
more modes of action, you must use two or more appropriate MoA identifier letters or numbers in a single
statement. Alternatively, each individual active ingredient can be placed in a stacked format (see examples
below).

If the product contains two or more active constituents which perform different functions, for example,
an insecticide and a fungicide, you must show each function separately (that is, one indicator panel for theinsecticide and another for the fungicide component). See examples below.

Where required, appropriate translation should be used to ensure MoA labels are clear to product users.
Labelling should also consider the FAO/WHO Guidelines on Good Labelling Practice for Pesticides. MoA
labelling must follow all country regulations and may vary.

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RESISTANCE MANAGEMENT LANGUAGE FOR PRODUCT LABELSIn addition to mode of action number labelling, it is strongly recommended by CLI and the Resistance
Action Committees (RACs) to include guidance on the management of resistance on the product label.
Where possible companies will voluntarily add resistance management language to their product labelsthat explains how to use MoA information in resistance management recommendations.
IRAC recommends that resistance management guidelines be presented under a headed section titled:“RESISTANCE MANAGEMENT” on all insecticide labels and the following three IRM elements beincorporated in the text.
•

The name of the active ingredient(s) and mode of action identifier (IRAC Mode of Action groups).

•

A statement that the product should be rotated with different modes of action using mode ofaction treatment windows.

•

Guidance to avoid treating consecutive generations with the same mode of action

EXAMPLE OF AN IRM RECOMMENDATION ON AN INSECTICIDE PRODUCT LABEL:PRODUCT NAME contains the ACTIVE INGREDIENT NAME and is an IRAC GROUP X insecticide. Do
not exclusively use PRODUCT NAME or other GROUP X insecticides to control the same pest
throughout the season. Avoid exposing consecutive generations of a pest to the same mode of action byusing the “application window” approach which rotates products from different mode of action groups.

An “application window” is the period of residual activity that a single application or sequential
applications of products from the same mode of action provide. It can also be defined as the duration of an
insect generation or if unknown, then use an approximate 30 day period. Rotate windows with treatmentsof PRODUCT NAME and other Group X products followed by windows of treatments with other effective
products with different modes of action. Multiple applications (recommend no more than two) of thesame MoA insecticide are acceptable if they are used within the same application window.
Reference: CropLife International Mode of Action Labelling GuidanceMode of Action Classification v11.1

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Appendix 2
IRM principles recommended and endorsed by IRAC•

Consult a local agricultural advisor or extension services in the area for up-to-date recommendations
and advice on IPM and IRM programmes.

•

Consider options for minimizing insecticide use by selecting early maturing or pest-tolerant varietiesof crop plants.

•

Include effective cultural and biological control practices that work in harmony with effective IRM
programmes. Adopt all non-chemical techniques known to control or suppress pest populations,
including biological sprays such as Bt’s, resistant varieties, within-field refugia (untreated areas) andcrop rotation.

•

Where possible select insecticides and other pest management tools that preserve beneficial insects.

•

Use products at their full, recommended doses. Reduced (sub-lethal) doses quickly select populations
with average levels of tolerance, whilst doses that are too high may impose excessive selection
pressures.

•

Appropriate, well-maintained equipment should be used to apply insecticides. Recommended water
volumes, spray pressures and optimal temperatures should be used to obtain optimal coverage.

•

Where larval stages are being controlled, target younger larval instars where possible because these
are usually much more susceptible and therefore much more effectively controlled by insecticides
than older stages.

•

Use appropriate local economic thresholds and spray intervals.

•

Follow label recommendations or local expert advice for use of alternations or sequences of different
classes of insecticide with differing modes of action as part of an IRM strategy.

•

Where there are multiple applications per year or growing season, alternate products of different
MoA classes.

•

In the event of a control failure, do not reapply the same insecticide but change the class ofinsecticides to one having a different MoA and to which there is no [locally] known cross-resistance.

•

Mixtures may offer a short-term solution to resistance problems, but it is essential to ensure that eachcomponent of a mixture belongs to a different insecticide MoA class, and that each component is usedat its full rate.

•

Consideration should be given to monitoring for the incidence of resistance in the most commercially
important situations and gauge levels of control obtained.

•

Withholding use of a product to which resistance has developed until susceptibility returns may be avalid tactic if sufficient alternative chemical classes remain to provide effective control.

Mode of Action Classification v11.1

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Appendix 3
MoA Group Descriptors
NERVE AND MUSCLE TARGETS
Most current insecticides act on nerve and muscle targets. Insecticides that act on these targets are
generally fast acting.

Group 1: Acetylcholinesterase (AChE) inhibitors
Inhibit AChE, causing hyperexcitation. AChE is the enzyme that terminates the action of the excitatoryneurotransmitter acetylcholine at nerve synapses.

Group 2: GABA-gated chloride channel blockers
Block the GABA-activated chloride channel, causing hyperexcitation and convulsions. GABA is the major
inhibitory neurotransmitter in insects.

Group 3: Sodium channel modulators
Keep sodium channels open, causing hyperexcitation and, in some cases, nerve block. Sodium channels
are involved in the propagation of action potentials along nerve axons.

Group 4: Nicotinic acetylcholine receptor (nAChR) competitive modulators
Bind to the acetylcholine site on nAChRs, causing a range of symptoms from hyper-excitation to lethargy
and paralysis. Acetylcholine is the major excitatory neurotransmitter in the insect central nervous system.

Group 5: Nicotinic acetylcholine receptor (nAChR) allosteric modulators – Site I
Allosterically activate nAChRs (at a site distinct from Group 32 - Site II), causing hyperexcitation of thenervous system. Acetylcholine is the major excitatory neurotransmitter in the insect central nervous
system.

Group 6: Glutamate-gated chloride channel (GluCl) allosteric modulators
Allosterically activate glutamate-gated chloride channels (GluCls), causing paralysis. Glutamate is an
important inhibitory neurotransmitter in insect.

Group 9: Chordotonal organ TRPV channel modulators
Bind to and disrupt the gating of Nan-Iav TRPV (Transient Receptor Potential Vanilloid) channel
complexes in chordotonal stretch receptor organs, which are critical for the senses of hearing, gravity,balance, acceleration, proprioception and kinesthesia. This disrupts feeding and other behaviors in target
insects.

Group 14: Nicotinic acetylcholine receptor (nAChR) channel blockers
Block the nAChR ion channel, resulting in nervous system block and paralysis. Acetylcholine is the major
excitatory neurotransmitter in the insect central nervous system.

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Group 19: Octopamine receptor agonists
Activate octopamine receptors, leading to hyperexcitation. Octopamine is the insect equivalent ofadrenaline, the fight-or-flight neurohormone

Group 22: Voltage-dependent sodium channel blockers
Block sodium channels, causing nervous system shutdown and paralysis. Sodium channels are involved in
the propagation of action potentials along nerve axons.

Group 28: Ryanodine receptor modulators
Activate muscle ryanodine receptors, leading to contraction and paralysis. Ryanodine receptors mediate
calcium release into the cytoplasm from intracellular stores.

Group 29: Chordotonal organ nicotinamidase inhibitors
Disrupt the function of chordotonal stretch receptor organs, which are critical for the senses of hearing,
gravity, balance, acceleration, proprioception and kinesthesia. This disrupts feeding and other behaviors
in target insects. Group 29 insecticides inhibit the enzyme nicotinamidase, which degrades theendogenous TRPV modulator nicotinamide.

Group 30: GABA-gated chloride channel allosteric modulators
Allosterically inhibit the GABA-activated chloride channel, causing hyperexcitation and convulsions.
GABA is the major inhibitory neurotransmitter in insects.

Group 32: Nicotinic acetylcholine receptor (nAChR) allosteric modulators – Site II
Allosterically activate nAChRs (at a site distinct from Group 5 - Site I), causing hyperexcitation of thenervous system. Acetylcholine is the major excitatory neurotransmitter in the insect central nervous
system.

Group 33: Calcium-activated potassium channel (KCa2) modulators
Negative modulation of KCa2 causes hyperexcitation and convulsions. KCa2 channels are activated byincrease of the intracellular calcium concentration and are involved in the regulation of action potentials.

Group 36: Chordotonal organ modulators – undefined target site
Disrupt the function of chordotonal stretch receptor organs, which are critical for the senses of hearing,
gravity, balance, acceleration, proprioception and kinesthesia. This disrupts feeding and other behaviors
in target insects. Group 36 insecticides act at a site different from Group 9 and Group 29 insecticides andare neither affecting TRPV channels nor nicotinamidase.

GROWTH AND DEVELOPMENT TARGETS
Insect development is controlled by the balance of two principal hormones: juvenile hormone andecdysone. Insect growth regulators act by mimicking one of these hormones or directly perturbing cuticle

Mode of Action Classification v11.1

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formation/deposition or lipid biosynthesis. Insecticides that act on individual targets in this system are
generally slow to moderately slow acting.

Group 7: Juvenile hormone mimics
Applied in the pre-metamorphic instar, these compounds disrupt and prevent metamorphosis.

Group 10: Mite growth inhibitors affecting CHS1
Inhibit the enzyme that catalyzes the polymerization of Chitin.

Group 15: Inhibitors of chitin biosynthesis affecting CHS1
Inhibit the enzyme that catalyzes the polymerization of Chitin.

Group 16: Inhibitors of chitin biosynthesis, type 1
Incompletely defined MoA leading to inhibition of chitin biosynthesis in a number of insects, including
whiteflies.

Group 17: Moulting disruptors, Dipteran
Incompletely defined MoA that leads to moult disruption.

Group 18: Ecdysone receptor agonists
Mimic the moulting hormone, ecdysone, inducing a precocious moult.

Group 23: Inhibitors of acetyl-CoA carboxylase
Inhibit acetyl coenzyme A carboxylase, part of the first step in lipid biosynthesis, leading to insect death.

RESPIRATION TARGETS
Mitochondrial respiration produces ATP, the molecule that energizes all vital cellular processes. In
mitochondria, an electron transport chain stores the energy released by oxidation in the form of a proton
gradient, which drives ATP synthesis. Several insecticides are known to interfere with mitochondrial
respiration by the inhibition of electron transport and/or oxidative phosphorylation. Insecticides that act
on individual targets in this system are generally fast to moderately fast acting.

Group 12: Inhibitors of mitochondrial ATP synthase
Inhibit the enzyme that synthesizes ATP.

Group 13: Uncouplers of oxidative phosphorylation via disruption of the proton gradientProtonophores that short-circuit the mitochondrial proton gradient so that ATP cannot be synthesized.

Group 20; Mitochondrial complex III electron transport inhibitors – Qo site
Inhibit electron transport complex III, preventing the utilization of energy by cells by binding to the Qo
site.

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Group 21: Mitochondrial complex I electron transport inhibitors
Inhibit electron transport complex I, preventing the utilization of energy by cells.

Group 24: Mitochondrial complex IV electron transport inhibitors
Inhibit electron transport complex IV, preventing the utilization of energy by cells.

Group 25: Mitochondrial complex II electron transport inhibitors
Inhibit electron transport complex II, preventing utilization of energy by cells.

Group 34: Mitochondrial complex III electron transport inhibitors – Qi site
Inhibit electron transport complex III, preventing the utilization of energy by cells. In contrast to Group20, Group 34 insecticides bind to the Qi site.

MIDGUT TARGETS
Lepidopteran-specific microbial toxins that are sprayed or expressed in transgenic crop varieties, andbaculoviruses.

Group 11: Microbial disruptors of insect midgut membranes
Protein toxins that bind to receptors on the midgut membrane and induce pore formation, resulting inionic imbalance and septicemia.

Group 31: Host-specific occluded pathogenic viruses
A baculovirus-unique Per os Infectivity Factor (PIF) protein complex on the virus promotes host-specificinfection by binding to PIF targets on midgut cells that are unknown but believed to be unique for eachbaculovirus type. Infection is ultimately lethal.

TARGETED PROTEIN SUPPRESSORS
Multiple biological processes govern the accumulation of proteins critical to supporting a wide variety offunctions within insects. Protein suppressors act through reduction of specific protein levels in the pest
species. Insecticides that act in this manner are generally moderately slow acting.

Group 35: RNA interference mediated target suppressors
Activation of the RNAi mechanism which specifically reduces abundance of the target messenger RNA(mRNA) resulting in the reduction of the protein encoded by the mRNA.

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UNKNOWN OR NON-SPECIFIC TARGETS
Several insecticides are known to affect less well-described target-sites or functions, or to act nonspecifically on multiple targets.

Group 8: Miscellaneous non-specific (multi-site) inhibitors
Group UN: Compounds of unknown or uncertain MoA
Group UNB: Bacterial agents of unknown or uncertain MoA
Group UNE: Botanical essence including synthetic, extracts and unrefined oils with unknown or
uncertain MoA
Group UNF: Fungal agents of unknown or uncertain MoA
Group UNM: Non-specific mechanical and physical disruptors
Group UNP: Peptides of unknown or uncertain MoA
Group UNV: Viral agents of unknown or uncertain MoA

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Appendix 4
Procedure for allocation of new insecticidal materials to the
MoA classification
IRAC maintains the MoA Classification scheme as the definitive, globally recognised, ultimate authority
on insecticide modes of action. In order to provide the best possible information for resistancemanagement purposes, IRAC also issues regular updates of the scheme, in which newly introduced
insecticides are allocated to an appropriate MoA classification group and structural sub-group, and inwhich re-classification or the correction of errors or anomalies for specific insecticidal agents isundertaken considering definitive new information. This document details how these processes areadministered by IRAC.

Who is responsible for the process within IRAC?
The IRAC MoA Team comprises technical representatives of the member companies with expertise ininsect toxicology, pharmacology or biochemistry. All IRAC companies are eligible to contribute technicalexpertise to the group. The group meets regularly to consider the content and detail of the MoA scheme
and makes proposals on significant additions, deletions or reallocations of insecticidal agents within thescheme for consideration by the IRAC Executive.

Why and how often is the scheme updated?
New versions of the scheme are issued periodically as necessary, as a result of the MoA Team’s
consideration of new information. The introduction of major new MoA groups or the reallocation of
insecticidal agents or groups would merit the issue of a new version (vN). Minor changes or corrections
that do not significantly impact the scheme are undertaken automatically at intervals as necessary, andsub-versions are issued (vN.n). New sub-versions may be issued up to several times per year as required,while new full versions are not anticipated more than once per year. The potential impact of proposed
significant changes on derived versions of the scheme around the world is fully appreciated, especially incountries where MoA labelling of products is used. The MoA team is cognisant of these impacts andrevisions are only proposed when the evidence for change is scientifically compelling.

What evidence is needed to support MoA classification of an
insecticidal agent?
Proposals for additions to the MoA scheme or for amendments to the current scheme should besubmitted to the IRAC MoA team (details below). These proposals will be considered by the Team and a

Mode of Action Classification v11.1

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decision on the outcome will be provided to the proposer in due course. Published material in highquality, front line, peer-reviewed, scientific journals is especially useful as a source of information for
consideration by the team, and those companies, bodies or individuals submitting proposals forconsideration by the team are strongly encouraged to provide such information wherever possible.
Corroborating information is also especially welcome. Unpublished material may be submitted inevidence, and the MoA team will interpret this appropriately.
Several types of data can be used to establish MoA (including the activation of pro-insecticides to theiractives). Convincing evidence to support the MoA hypothesis is needed. This includes the demonstrationof a clear target effect (activation, inhibition, or modulation) at concentrations that can reasonably be
expected in the intoxicated organism. Preferably, these data may be corroborated by physiological and/or
symptomology studies to link insect mortality to the effect on the target site. A positive structure-activity
correlation of in vitro efficacy with insecticidal potency, and/or target site mutations conferring
resistance are required to further substantiate the proposed MoA.

What are the criteria for establishing MoA Sub-groups?
Sub-groups represent distinct chemical classes that are believed to have the same MoA but are different
enough in chemical structure or mode of interaction with the target protein that the chance of selection
for either metabolic or target-site cross-resistance is reduced compared to close analogs. Sub-groups may
also distinguish insecticidal agents that are structurally similar but known to bind differently within thetarget or to have differential selectivity among multiple targets. Evidence supporting lack of crossresistance between existing compounds within the Group and the new active ingredient submission must
be provided to support sub-grouping. This should include bioassay based studies and provide quantifiable
resistance ratios between susceptible and resistant strains.
The cross-resistance potential between sub-groups is higher than that between different groups, sorotation between sub-groups should be avoided. In exceptional circumstances (i.e., where effective
registered insecticides from other mode of action groups are unavailable) rotation may be consideredfollowing consultation with local expert advice and where cross-resistance does not exist. These
exceptions should not be considered sustainable resistance management strategies, and alternative
options should be sought to maintain pest susceptibility.

How are decisions made by the MoA Team?
Given the definitive nature of the IRAC MoA scheme, the MoA Team regards it as an absolute prioritythat the highest levels of scientific integrity are always employed in the consideration and discussion of
allocation of insecticidal agents. In general, agreement on allocation of an insecticidal agent is usually
arrived at through consensus within the Team, following detailed discussion. Major decisions, forexample the introduction of new MoA classes or sub-classes are proposed to the IRAC Executive for
ratification. If the Team cannot agree it may choose to place the case with a panel of external MoA
experts to gain their written opinion before reconsidering the case. The composition of the expert panel

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is agreed in advance by the Team. If after reconsidering the particular case the team is still indisagreement, the matter will be passed to the IRAC Executive for further consideration. Where
individual members of the Team are subject to a conflict of interests through company affiliation or otherinterests, they may choose to withdraw from discussion of particular insecticidal agents as they consider
appropriate.

How long does this process take?
The MoA Team has a duty to make a definitive decision on allocation of an insecticidal agent as quickly as
possible following receipt of appropriate supporting evidence. For straightforward cases that do not
require external consultation it should generally be expected that the Team could provide feedback toproposers within 3 months. The need for external consultants may extend the process to 6 months.

To whom should proposals be sent?
Proposals for new insecticidal agents or for changes to the current IRAC MoA scheme should besubmitted to the IRAC MoA Team via the IRAC International Coordinator. A link to the coordinator isprovided on the IRAC website (www.irac-online.org) at the bottom of each page under ‘Contact’.
Alternatively, the online request can be completed at http://www.irac-online.org/submit-an-active/

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Procedure for updates to IRAC MoA Classification Scheme
Proposer submits a request for classification of a
new AI or change of classification of an existing AI
https://irac-online.org/submit-an-active/

Supporting information is submitted
to the IRAC MoA Team

Proposer is advised
if more information isneededReview and assessment by
IRAC MoA Team

Proposer is advisedof IRAC Executive
decision

Decision is ratified by IRAC
Executive or vote is taken if
there is disagreement

External peer-review
as necessary

MoA Scheme is updated in due course by MoA
Team either as a new version or sub-version

Mode of Action Classification v11.1

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MoA Classification Guidance Matrix
Supporting Evidence for Classification

Links

1. Existing Groupa. Existing Subgroup / no Subgroup• Demonstration of a clear effect (activation, inhibition, or modulation)on the target / signal transduction pathway at concentrations that canreasonably be expected in the intoxicated organism• A positive structure-activity correlation of in vitro efficacy with
insecticidal potency and/or• Target site mutation(s) supporting the proposed MoA

https://iraconline.org/documents/establishedinsecticide-target-sitemutations/?ext=xls• Physiological and/or symptomology studies to link insect mortality to
the effect on the target site / signal transduction pathway
b. New Subgroup (additional evidence required)• Distinct chemical / biological class*
Evidence supporting lack of cross-resistance between existing
compounds within the Group and the new active ingredient:• Quantifiable resistance ratios between field-relevant susceptible andresistant strains• In vitro studies (optional)

resistance profiles of relevant
pests incl. references
https://irac-online.org/pests/* Sub-groups may also distinguish insecticidal agents that are structurally similar but known to bind differently
within the target or to have differential selectivity among multiple targets.

2. New Group• New chemical / biological class• Demonstration of a clear effect (activation, inhibition, or modulation)on the target / signal transduction pathway at concentrations that canreasonably be expected in the intoxicated organism• A positive structure-activity correlation of in vitro efficacy with
insecticidal potency and/or• Target site mutation(s) supporting the proposed MoA• Physiological and/or symptomology studies to link insect mortality to
the effect on the target site / signal transduction pathway• Clear differentiation from existing sites in a known target / signaltransduction pathway is required if activity on a new site in an existingtarget / signal transduction pathway is claimed: this might include
experimental evidence that the insecticidal agent binds to a unique siteof an existing target which is not impacted by mutations conferring
resistance to the existing target

searchable online version of the
MoA Classification
https://www.irac-online.org/modesof-action/

3. Unknown Mode of Action
If there is insufficient evidence supporting a defined Mode of Action,
insecticidal / acarididal agents can be included in the classification
scheme in the Unknown Mode of Action category they fall under:
compounds, UN; bacterial agents, UNB; extracts and crude oils, UNE;
fungal agents, UNF; mechanical and physical disruptors, UNM;
peptides, UNP; viruses UNV

Mode of Action Classification v11.1

34

Appendix 5
ACTIVE INGREDIENTS (ALPHABETICAL ORDER) WITH MOA
CLASSIFICATION.
This is the comprehensive reference list of IRAC-classified insecticides. If your active ingredient is not on
this list and falls within the scope of this classification as defined in section 1, please contact IRAC as
directed in Appendix 4.
MOA

Active IngredientNo.

Active Ingredient

MOA
No.

1,3-dichloropropene

8A

Azamethiphos

1B

Abamectin

6

Azinphos-ethyl

1B

Acephate

1B

Azinphos-methyl

1B

Acequinocyl

20B

Azocyclotin

12B

Acetamiprid

4A

Bacillus thuringiensis

11A

Acrinathrin

3A

Bacillus sphaericus

11B

Acynonapyr

33

Beauveria bassiana strains

UNF

Afidopyropen

9D

Bendiocarb

1A

Akanthomyces muscarius Ve6

UNF

Benfuracarb

1A

Alanycarb

1A

Bensultap

14

Aldicarb

1A

Benzoximate

UN

Allethrin

3A

BenzpyrimoxanUNalpha-Cypermethrin

3A

beta-Cyfluthrin

3A

Aluminium phosphide

24A

beta-Cypermethrin

3A

Amitraz

19

Bifenazate

20D

Anticarsia gemmatalis MNPV

31

Bifenthrin

3A

Azadirachtin

UN

Bioallethrin

3A

Mode of Action Classification v11.1

35

Active Ingredient

MOA
No.

Bioallethrin S-cyclopentenyl
isomer

3A

Bioresmethrin

3A

Bistrifluron

15

Borax

8D

Boric acid

8D

Broflanilide

30

Bromopropylate

UN

Buprofezin

16

Burkholderia spp,

UNB

Butocarboxim

1A

Butoxycarboxim

1A

Cadusafos

1B

Calcium cyanide

24B

Calcium phosphide

24A

Carbaryl

1A

Carbofuran

1A

Carbosulfan

1A

Cartap hydrochloride

14

Chenopodium ambrosioides
near ambrosioides extract
Chinomethionat

Active Ingredient

MOA
No.

Chlorantraniliprole

28

Chlordane

2A

Chlorethoxyfos

1B

Chlorfenapyr

13

Chlorfenvinphos

1B

Chlorfluazuron

15

Chlormephos

1B

Chloropicrin

8B

Chlorpyrifos

1B

Chlorpyrifos-methyl

1B

Chromafenozide

18

Clofentezine

10A

Clothianidin

4A

Coumaphos

1B

Cryolite

8C

Cyanide24B

Cyanophos

1B

Cyantraniliprole

28

Cyclaniliprole

28

UNE

Cycloprothrin

3A

UN

Cydia pomonella GV

31

Mode of Action Classification v11.1

36

Active Ingredient

MOA
No.

Active Ingredient

MOA
No.

Cyenopyrafen

25A

Diflovidazin

10A

Cyflumetofen

25A

Diflubenzuron

15

Cyfluthrin

3A

Dimethoate

1B

Cyhalothrin

3A

Dimethylvinphos

1B

Cyhexatin

12B

Dimpropyridaz

36

Cypermethrin

3A

Dinotefuran

4A

Cyphenothrin (1R)-transisomers]

3A

Disodium octaborate

8D

Disulfoton

1B

Cyromazine

17

DNOC

13

d-cis-trans Allethrin

3A

d-trans Allethrin

3A

Dazomet

8F

Emamectin benzoate

6

DDT

3B

Empenthrin [(EZ)-(1R)-isomers]

3A

Deltamethrin

3A

Endosulfan

2A

Demeton-S-methyl

1B

EPN

1B

Diafenthiuron

12A

Esfenvalerate

3A

Diatomaceous earth

UNM

Ethiofencarb

1A

Diazinon

1B

Ethion1B

Dichlorvos/ DDVP

1B

Ethiprole

2B

Dicloromezotiaz

4E

Ethoprophos

1B

DicofolUN

Etofenprox

3A

Dicrotophos

1B

Etoxazole

10B

Mode of Action Classification v11.1

37

Active Ingredient

MOA
No.

Famphur

1B

Fatty acid monoesters withglycerol or propanediol

UNE

Fenamiphos

1B

Fenazaquin

21A

Fenbutatin oxide

12B

Fenitrothion

1B

Fenmezoditiaz

4E

Fenobucarb

1A

Fenoxycarb

7B

Fenpropathrin

3A

Fenpyroximate

21A

Fenthion

1B

Fenvalerate

3A

Fipronil

2B

Flometoquin

34

Flonicamid

29

Fluacrypyrim

20C

Flubendimide

28

Flucycloxuron

15

Flucythrinate

3A

Active Ingredient

MOA
No.

Flufenoxuron

15

Flumethrin

3A

Flupyradifurone

4D

Flupyrimin

4F

Fluxametamide

30

Formetanate

1A

Fosthiazate

1B

Furathiocarb

1A

gamma-Cyhalothrin

3A

GS-omega/kappa HXTX-Hv1a

32

Halfenprox

3A

Halofenozide

18

Helicoverpa armigera NPV

31

Heptenophos

1B

Hexaflumuron

15

Hexythiazox

10A

Hydramethylnon

20A

Hydroprene

7A

Imicyafos

1B

Imidacloprid

4A

Imiprothrin

3A

Mode of Action Classification v11.1

38

MOA

Active IngredientNo.

Active Ingredient

MOA
No.

Indoxacarb

22A

Methidathion

1B

Isocyloseram

30

Methiocarb

1A

Isofenphos

1B

Methomyl

1A

Isoprocarb

1A

Methoprene

7A

Methoxychlor

3B

Methoxyfenozide

18

Methyl bromide

8A

Methyl isocyanate

8F

Metolcarb

1A

Mevinphos

1B

Milbemectin

6

Mineral oil

UNM

Monocrotophos

1B

Naled

1B

Neem oil

UNE

Nicotine

4B

Nitenpyram

4A

Novaluron

15

Noviflumuron

15

Omethoate

1B

Oxamyl

1A

Isopropyl O- (methoxyaminothiophosphoryl) salicylate

1B

Isoxathion

1B

Kadethrin

3A

Kinoprene

7A

lambda-Cyhalothrin

3A

Ledprona

35

Lepimectin

6Lime sulfur

UN

Lufenuron

15

Malathion

1B

MancozebUN

Mecarbam

1B

Metaflumizone

22B

Metam

8F

Metarhizium brunneum strain
F52
Methamidophos

UNF
1B

Mode of Action Classification v11.1

39

MOA

Active IngredientNo.

Active Ingredient

MOA
No.

Oxazosulfyl

UN

Propetamphos

1B

Oxydemeton-methyl

1B

Propoxur

1A

Prothiofos

1B

Pyflubumide

25B

Pymetrozine

9B

Pyraclofos

1B

Pyrethrins (pyrethrum)

3A

Pyridaben

21A

PyridalylUN

Pyridaphenthion

1B

Pyrifluquinazon

9B

Pyrimidifen

21A

Pyriproxyfen

7C

Quinalphos

1B

Resmethrin

3A

Rotenone (Derris)

21B

Silafluofen

3A

Sodium borate

8D

Sodium cyanide

24B

Sodium metaborate

8D

Spidoxamat

23

Paecilomyces fumosoroseus

UNF

Apopka strain 97
Parathion

1B

Parathion-methyl

1B

Permethrin

3A

Phenothrin [(1R)- trans- isomer]

3A

Phenthoate

1B

Phorate

1B

Phosalone

1B

Phosmet1B

Phosphamidon

1B

Phosphine

24A

Phoxim

1B

Pirimicarb

1A

Pirimiphos- methyl

1B

Potassium cyanide

24B

Prallethrin

3A

Profenofos

1B

Propargite

12C

Mode of Action Classification v11.1

40

Active Ingredient

MOA
No.

Active Ingredient

MOA
No.

Spinetoram

5

Tetradifon

12D

Spinosad5

Tetramethrin

3A

Spirodiclofen

23

Tetramethrin [(1R)- isomers]

3A

Spiromesifen

23

Tetraniliprole

28

Spriropidion

23

Thaumatotibia leucotreta GV

31Spirotetramat

23

theta-cypermethrin

3A

Sulfotep

1B

Thiacloprid

4A

Sulfoxaflor

4C

Thiamethoxam

4A

SulfurUN

Thiocyclam

14

Sulfuramid

13

Thiodicarb

1A

Sulfuryl fluoride

8C

Thiofanox

1A

Tartar emetic

8E

Thiometon

1B

tau-Fluvalinate

3A

Thiosultap-sodium

14

Tebufenozide

18

Tolfenpyrad

21A

Tebufenpyrad

21A

Tralomethrin

3A

Tebupirimfos

1B

Transfluthrin

3A

Teflubenzuron

15

Triazamate

1A

Tefluthrin

3A

Triazophos

1B

Temephos

1B

Trichlorfon

1B

Terbufos

1B

Triflumezopyrim

4E

Tetrachlorvinphos

1B

Triflumuron

15

Mode of Action Classification v11.1

41

Active Ingredient

MOA
No.

Trimethacarb

1A

Vamidothion

1B

Wolbachia pipientis (Zap)

UNB

XMC

1A

Xylylcarb

1A

zeta-Cypermethrin

3A

Zinc phosphide

24A

Mode of Action Classification v11.1

42

Appendix 6
Active Ingredients Pending Registration
Group numbers are proposed at this stage - the final number will be confirmed
following the first registration.
Main Group and Primary Site of

Sub-group, class or

Actionexemplifying Active

Active IngredientIngredient

UNP
Peptides of unknown or uncertain
MoA

U1-AGTX-Ta1b-QA
PeptideU1-AGTX-Ta1b-QA Peptide

Mode of Action Classification v11.1

43