Agriculture: Pistachio Pest Management Guidelines

General Properties of Fungicides Used in Pistachios

Common name
(example trade name)
Chemical class (FRAC # )1 Activity Mode of action Resistance potential
azoxystrobin (Abound) QoI2 (11) contact, systemic single-site high
boscalid (Endura) carboxamide (7) contact single-site high
cyprodinil (Vangard) anilinopyrimidine (9) mostly contact single-site high
cyprodinil / fludioxonil (Switch) anilinopyrimidine / phenylpyrrole (9 / 12) contact, slightly systemic single-site / single-site medium
fenhexamid (Elevate) hydroxyanilide (17) contact single-site high
iprodione (Rovral) dicarboximide (2) systemic (local) single-site medium
pyraclostrobin (Cabrio) QoI2 (11) contact, systemic (local) single-site high
pyrimethanil (Scala) anilinopyrimidine (9) slightly systemic (local) single-site high
tebuconazole (Elite) DMI3-triazole (3) systemic (local) single-site high
Reynoutria sachalinensis extract plant extract (P5) various low
thiophanate-methyl (Topsin-M) MBC5 (1) systemic (local) single-site very high
trifloxystrobin (Gem) Qol2 (11) contact, systemic4 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 http://www.frac.info/). 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, 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 fungicide with a different mode-of-action group number.
2 QoI = quinone outside inhibitor (strobilurin).
3 DMI = demethylation (sterol) inhibitor.
4 Generally considered to have systemic action based on performance data but has not been proven experimentally.
5 MBC= methyl benzimidazole carbamate.

Acknowledgment: Adaskaveg et al., 2017. Efficacy and Timing of Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops. (PDF)

Text Updated: 10/14