Agriculture: Strawberry Pest Management Guidelines

General Properties of Fungicides Used in Strawberries

Common name
(Example trade name)
Class Group (FRAC) number1 Activity Mode of action Resistance potential Comments
azoxystrobin (Abound, Quadris Top) Qol4 11 contact,
systemic2
single-site high7 Resistance in Botrytis and Colletotrichum documented
captan phthalimide M4 contact multi-site very low to low toxic to honey bee larvae
chlorothalonil (Bravo) chloronitrile M5 contact multi-site low
cyflufenamid (Torino) phenyl-acetamide U6 contact high
cyprodinil/fludioxonil (Switch) anilinopyrimidine/phenylpyrrole 9/12 contact/slightly systemic single-site/single-site medium to high
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, systemic single-site/single-site medium to high
fosetyl-al (Aliette) phosphonates P07, 33 systemic unknown low
insecticidal soap (M-pede) inorganic salt contact low to medium
iprodione (Rovral) dicarboximide 2 systemic (local) single-site? low to medium 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 P07, 33 systemic unknown (multi-site?) medium
pyraclostrobin/boscalid (Pristine) Qol4/SDHI5 11/7 contact, systemic2 single-site/single-site medium to high Resistance in Botrytis documented
pyraclostrobin/fluxapyroxad (Merivon) Qol4/SDHI5 11/7 contact, systemic2 single-site/single-site medium to high
quinoxyfen (Quintec) quinolines 13 contact single-site medium to high
sulfur inorganic M2 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 very high7 Resistance in Botrytis documented
thiram dithiocarbamates M3 contact multi-site low
triflumizole (Procure) DMI3-triazole 3 systemic (local)2 single-site high7
1 Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of action. Fungicides with different group numbers are suitable to alternate in a resistance management program. In California, make no more than one application of a fungicide with a mode-of-action group number associated 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 Generally considered to have systemic action based on performance data but has not been proven experimentally.
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 group 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., 2022. Fungicides, Bactericides, Biocolntrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops in California. (PDF)

Text Updated: 07/18