| Common name (Example trade name) |
Class | Group (FRAC) number1 | Activity | Mode of action | Resistance potential | Comments |
|---|---|---|---|---|---|---|
| azoxystrobin (Abound, Quadris) | Qol4 | 11 | contact, systemic2 |
single-site | high7 | Resistance in Botrytis and Colletotrichum documented |
| captan | phthalimide | M 04 | contact | multi-site | low | toxic to honey bee larvae |
| chlorothalonil (Bravo) | chloronitrile | M 05 | contact | multi-site | low | |
| cyflufenamid (Torino) | phenyl-acetamide | U 06 | contact | unknown | high | |
| cyprodinil/fludioxonil (Switch) | anilinopyrimidine/phenylpyrrole | 9/12 | contact/slightly systemic | single-site/single-site | medium | |
| fenhexamid (Elevate) | hydroxyanilide | 17 | contact | single-site | high7 | Resistance in Botrytis documented |
| fluopyram (Luna Privilege) | SDHI5 | 7 | contact | single-site | high7 | |
| fluopyram/trifloxystrobin (Luna Sensation) | SDHI5/Qol4 | 7/11 | contact, systemic2 | single-site/single-site | medium | |
| fosetyl-al (Aliette) | phosphonates | P 07, 33 | systemic | unknown | high | |
| potassium salts of fatty acids (M-pede) | inorganic salt | NC | contact | — | medium | |
| iprodione (Rovral) | dicarboximide | 2 | systemic (local) | single-site? | high | toxic to honey bee larvae |
| isofetamid (Kenja) | SDHI5 | 7 | contact | single-site | high7 | |
| mefenoxam (Ridomil Gold) | phenylamide | 4 | contact, systemic | single-site | high7 | |
| myclobutanil (Rally) | DMI3-triazole | 3 | systemic (local)2 | single-site | high | |
| penthiopyrad (Fontelis) | SDHI5 | 7 | contact | single-site | high7 | |
| phosphorous acid (Fosphite) | phosphonates | P 07, 33 | systemic | unknown (multi-site?) | medium | |
| pyraclostrobin/boscalid (Pristine) | Qol4/SDHI5 | 11/7 | contact, systemic2 | single-site/single-site | medium | Resistance in Botrytis documented |
| pyraclostrobin/fluxapyroxad (Merivon) | Qol4/SDHI5 | 11/7 | contact, systemic2 | single-site/single-site | medium | |
| quinoxyfen (Quintec) | quinoline | 13 | contact | single-site | high | |
| sulfur | inorganic | M 02 | contact | multi-site | low | |
| tetraconazole (Mettle) | DMI3-triazole | 3 | systemic (local)2 | single-site | high | |
| thiophanate-methyl (Topsin-M) | MBC6 | 1 | systemic (local) | single-site | high7 | Resistance in Botrytis documented |
| thiram | dithiocarbamates | M 03 | contact | multi-site | low | |
| triflumizole (Procure) | DMI3-triazole | 3 | systemic (local)2 | single-site | high |
| 1 | Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions (for more information see www.frac.info). Fungicides with a different mode-of-action group number are suitable to alternate in a resistance management program. In California, make no more than one application of fungicides with mode-of-actions group number with high resistance risk before rotating to a fungicide with a different mode-of-action group number; for other fungicides, make no more than two consecutive applications before rotating to fungicide with a different mode-of-action group number. |
| 2 | Unsure or lacking scientific evidence. These fungicides are generally considered to have systemic action based on performance data but may not have been proven using lab assays (e.g. radioactively labeled compounds). |
| 3 | DMI = demethylation (sterol) inhibitor |
| 4 | Qol = quinone outside inhibitor (strobilurin) |
| 5 | SDHI = succinate dehydrogenase inhibitor |
| 6 | MBC = methyl benzimidazole carbamate |
| 7 | Resistance has been found in California for certain fungicides with a single-site mode of action. To reduce the risk of resistance development, take the mode of action into account when choosing a fungicide. At the beginning of a treatment program, use a fungicide with a multi-site mode of action; for subsequent applications rotate or mix fungicides with different mode of action FRAC numbers. Use labeled rates (preferably the upper range) of the single-site fungicides, and limit the total number of applications per season. |
Acknowledgment: Adaskaveg et al., 2025. Fungicides, Bactericides, Biocolntrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops in California.