Agriculture: Onion and Garlic Pest Management Guidelines

General Properties of Fungicides

Common name (Example trade name) Chemical class Activity Mode of action (FRAC1) Resistance potential
ametoctradin/ dimethomorph (Zampro) QoSI5/carboxilic acid amides locally systemic single-site (45)/ single-site (40) medium
azoxystrobin (Quadris) QoI2 contact, systemic single-site (11) high
azoxystrobin/ difenoconazole (Quadris Top) QoI2/DMI3 contact, systemic single-site (11)/single-site (3) medium
boscalid (Endura) SDHI4 locally systemic single-site (7) medium to high
boscalid/pyraclostrobin (Pristine) SDHI4/QoI2 contact, locally systemic single-site (7)/single-site (11) medium to high
chlorothalonil (Bravo, Echo) aromatic chloronitriles contact multi-site (M5) low
copper compounds (Basic Copper 53, Kocide) inorganic contact multi-site (M1) low
difenoconazole/ cyprodinil (Inspire Super) DMI3/anilino-pyrimidine systemic/locally systemic single-site (3)/single-site (9) medium
dimethomorph (Forum) carboxilic acid amides locally systemic single-site (40) low to medium
fenamidone (Reason) QoI2 contact, locally systemic single-site (11) high
fluazinam (Omega) 2,6-dinitro-alanines contact, locally systemic single-site (29) low
fludioxonil (Cannonball) phenylpyrroles contact single-site (12) low to medium
fluopyram/tebuconazole (Luna Experience) SDHI4/DMI3 locally systemic/systemic single-site (7)/ single-site (3) medium
iprodione (Rovral) dicarboxamide contact, locally systemic single-site (2) medium to high
mancozeb (Dithane) dithiocarbamate (EBDC) contact multi-site (M3) low
mancozeb/mefenoxam (Ridomil Gold MZ WG) dithiocarbamate (EBDC)/ phenylamide contact/systemic multi-site (M3)/single-site (4) medium to high
mefenoxam/ chlorothalonil (Ridomil Gold Bravo SC) phenylamide/ aromatic nitrile systemic/contact single-site (4)/multi-site (M11) medium to high
oxathiapiprolin/ mandipropamid (Orondis Ultra) OSBPI6/ carboxylic acid amides systemic/locally systemic single-site (49)/single-site (40) medium
penthiopyrad (Fontelis) SDHI4 contact, locally systemic single-site (7) high
pyraclostrobin (Cabrio) QoI2 contact, locally systemic single-site (11) high
pyraclostrobin/ fluxapyroxad (Merivon Xemium) QoI2/SDHI4 locally systemic single-site (11)/ single-site (7) medium to high
pyrimethanil/fluopyram (Luna Tranquility) anilino-pyrimidine/ SDHI4 locally systemic single-site (9)/ single-site (7) medium to high
tebuconazole (Orius) DMI3-triazole systemic  single-site (3) high
1 Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of action. Fungicides with a different group number are suitable to alternate in a resistance management program. In California, make no more than one application of fungicides with mode-of-action group numbers 1, 4, 7, 9, 11, or 17 before rotating to a fungicide with a different mode-of-action group number; for fungicides with other group numbers, make no more than two consecutive applications before rotating to a fungicide with a different mode-of-action group number.
2 QoI = quinone outside inhibitor (strobilurin).
3 DMI = demethylation (sterol) inhibitor.
4 SDHI = succinate dehydrogenase inhibitors.
5 QoSI = quinone outside inhibitor, stigmatellin binding type.
6 OSBPI = oxysterol binding protein inhibition.
Text Updated: 02/19