liminfoFRAC/IRAC/HRAC Reference
Free reference guide: FRAC/IRAC/HRAC Reference
About FRAC/IRAC/HRAC Reference
This FRAC/IRAC/HRAC Reference is a searchable quick-reference guide for pesticide mode-of-action classification systems. It covers major FRAC fungicide groups (MBC, DMI, SDHI, QoI, multi-site), IRAC insecticide groups (AChE inhibitors, pyrethroids, neonicotinoids, avermectins, diamides), and HRAC herbicide groups (ACCase, ALS, PSII, EPSPS, GS, PPO) with active ingredients, target sites, and resistance risk ratings.
Beyond classification, the reference provides detailed integrated resistance management (IRM) strategies including rotation spraying, tank-mix protocols, window strategies for high-risk agents, label reading guidelines, resistance monitoring methods with molecular markers, cross-resistance patterns, and IPM integration combining chemical, cultural, physical, and biological control methods.
Designed for agronomists, crop protection specialists, plant pathologists, extension officers, and agricultural students, this guide enables quick lookup of FRAC/IRAC/HRAC codes, safe use parameters (PHI and MRL), and practical resistance management decision-making in field conditions.
Key Features
- Complete FRAC fungicide group reference including MBC, DMI, SDHI, QoI, and multi-site agents with resistance risk levels
- IRAC insecticide classification covering AChE inhibitors, Na channel modulators, neonicotinoids, GluCl agonists, and diamides
- HRAC herbicide group guide for ACCase, ALS, PSII, EPSPS, GS, and PPO inhibitors with target site details
- IRM strategy reference for rotation spraying, tank-mix protocols, and window-based application timing
- Cross-resistance pattern guide explaining within-group resistance and molecular markers like G143A
- PHI (pre-harvest interval) and MRL (maximum residue limit) safety reference with crop-specific examples
- IPM integration guide combining cultural, physical, biological, and chemical control methods
- Resistance monitoring methods including discriminating dose assays, EC50 comparisons, and molecular diagnostics
Frequently Asked Questions
What pesticide classification systems does this reference cover?
This reference covers all three major resistance action committee systems: FRAC (Fungicide Resistance Action Committee) with groups 1, 3, 7, 11, and M; IRAC (Insecticide Resistance Action Committee) with groups 1, 3, 4, 6, and 28; and HRAC (Herbicide Resistance Action Committee) with groups 1, 2, 5, 9, 10, and 14. Each entry includes active ingredients, target sites, and resistance risk ratings.
How do I find the FRAC code for a specific fungicide?
Search by the active ingredient name or browse the FRAC (Fungicides) category. For example, searching "tebuconazole" will show FRAC Group 3 (DMI), while "azoxystrobin" appears under FRAC Group 11 (QoI). Each entry lists the FRAC code, mode of action, representative active ingredients, and resistance risk level.
What resistance management strategies are included?
The reference covers five IRM strategies: rotation spraying (alternating different MOA groups), tank-mix protocols (combining agents with different MOA), window strategies (restricting high-risk agents to specific growth stages), anti-resistance label reading guidelines, and resistance monitoring using discriminating dose assays and molecular markers.
Does this reference explain cross-resistance between pesticides?
Yes, the cross-resistance entry explains that agents within the same FRAC/IRAC/HRAC group share cross-resistance risk. For example, azoxystrobin resistance from the G143A mutation confers resistance to all QoI fungicides. Agents in different groups generally do not show cross-resistance.
What are PHI and MRL and where can I find them?
PHI (Pre-Harvest Interval) is the minimum number of days between the last pesticide application and harvest. MRL (Maximum Residue Limit) is the maximum pesticide residue allowed in food, measured in mg/kg. The Safe Use category provides crop-specific examples for both, such as tebuconazole on rice (PHI 21 days) and glyphosate on wheat (MRL 30 mg/kg).
How does this reference help with IPM planning?
The IPM entry integrates four control methods: cultural (crop rotation, resistant varieties, planting date adjustment), physical (traps, mulching, heat treatment), biological (natural enemies, microbial agents), and chemical (IRM-compliant spraying). The reference helps select appropriate combinations for sustainable pest management.
Which neonicotinoid insecticides are listed under IRAC Group 4?
IRAC Group 4A lists imidacloprid, thiamethoxam, and clothianidin as representative neonicotinoids. The entry notes their nAChR competitive modulator mode of action, medium resistance risk, and the important pollinator toxicity concern that requires careful application management.
Is this reference free to use?
Yes, this FRAC/IRAC/HRAC reference is completely free with no usage limits or account required. All content loads in your browser with no server processing. It is part of liminfo.com's collection of free online reference tools for agriculture professionals.