Agriculture: Citrus Pest Management Guidelines

Fungicide Efficacy for Citrus Diseases

Fungicide*** Resistance risk
(FRAC group number)1,5
Phytophthora2 Septoria spot Anthracnose Alternaria rot Greasy spot Rind disorder
brown rot root rot
Abound high (11)5 NL 0 4 4 2 4 0
Aliette, ProPhyt, Fungi-Phite, K-Phite low to medium (P07, 33) 4 4 3 3 1 ND 0
Bumper, Tilt3 high (3) 0 0 NL NL NL 4 0
Copper low (M1) 4 0 4 3 1 3 0
Enable high (3) 0 0 NL NL 1 4 0
Ferbam**   low (M3) NL NL 0 3 0 0 0
Flint Extra high (11)5 NL 0 4 4 2 4 0
Headline high (11)5 NL 0 4 4 2 4 0
Luna Sensation medium (7/11)5 NL 0 5 5 2 4 0
Mibelya* medium (3/7)5 NL 0 5 5 2 4 0
Miravis Prime**4 medium (7/12) 0 0 5 5 2 4 0
Orondis high (49) 5 5 0 0 0 0 0
Ph-D, Oso high (19) NL NL 4 4 1 0 0
Presidio high (43) NL 5 0 0 0 0 0
Priaxor medium (7/11)5 NL 0 5 5 2 4 0
Pristine medium (7/11)5 NL 0 4 4 2 4 0
Quadris Top medium (3/11) NL 0 5 5 3 4 0
Revus high (40) 5 NL 0 0 0 0 0
Ridomil Gold, Mefenoxam high (4) NL 3 0 0 0 0 0
Ridomil, Metalaxyl high (4) NL 3 0 0 0 0 0
Scala4 high (9) 0 0 NL NL 1 NL 0
Sulfur low (M2) 0 0 0 0 0 3 0
Switch4 medium (9/12) 0 0 5 5 2 4 0
Vapor Gard anti-transpirant 0 0 0 0 0 0 5
Rating: 5 = excellent and consistent, 4 = good and reliable, 3 = moderate and variable, 2 = limited and/or erratic, 1 = minimal and often ineffective, 0 = ineffective, NL = not on label, and ND = no data.
*   Registration pending in California.
**  Not registered, label withdrawn or inactive in California.
*** Postharvest fruit registrations in California include: BioSpectra/Cerafruta/Uniguard, Imazalil/Deccocil/Fungaflor, Graduate/FDL, GraduateA+, Azoxy, Mentor, Penbotec/Pyrimethanil, and Alumni/Decco Salt No. 19/TBZ.
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 Do not use the same fungicide or fungicides with similar chemistry more than twice in one year.
3 Only for non-bearing citrus.
4 Only federally registered on lemons and/or limes (check label).
5 To reduce the risk of resistance development, start treatments with a fungicide with a multi-site mode of action; rotate or mix fungicides with different mode of action FRAC numbers for subsequent applications, use labeled rates (preferably the upper range), and limit the total number of applications per season.

Acknowledgment: Adaskaveg et al., 2022. Fungicides, Bactericides, Biocontrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops in California. (PDF)

Text Updated: 03/22