Agriculture: Pistachio Pest Management Guidelines

Fungicide Efficacy for Pistachio Diseases

Fungicide Resistance risk (FRAC#)1 Alternaria late blight Botrytis blossom & shoot blight Botryosphaeria panicle & shoot blight
Fontelis high (7) ++++ ++++ +++/++++
Luna Experience medium (3/7) ++++ ++++ ++++
Luna Sensation medium (7/11)3 ++++4 ++++ ++++
Merivon high (7/11) ++++ ++++ ++++
Pristine high (7/11)3 ++++4 ++++ ++++
Quash high (3) ++++ +++/++++ +++5
Quilt Xcel,Avaris 2XS medium (3/11)3 ++++ ---- +++/++++
Viathon medium (3/33) ++++ + ++++5
Abound high (11) 2,3 +++ ---- +++
Cabrio high (11) 2,3 +++ ---- +++
Gem high (11) 2,3 +++ ---- +++
Ph-D medium (19) +++ ++++ +++
Quadris Top medium (3/11)3 +++ ---- +++/++++
Switch high (9/12)3 +++ +++ ++
Tebucon,Teb,Toledo high (3) +++ + +++5
Vangard high (9)3 +++ ++++ ----
Bravo,Chlorothalonil,
Echo
low (M5) ++ ---- ++
Bumper,Tilt high (3) ++ + ++5
Scala high (9)3 ++ +++ +++6
Inspire Super medium (3/9) ++ +++ +++/++++
Topsin-M,T-Methyl, Incognito,Cercobin7 high (1) ---- ++ ++
Elevate high (17)3 ND ++++ ND
K-Phite low (33) ND ND +++/++++
Organic treatments
Actinovate low ++ ++++ +++
Regalia low (natural product) ++ ---- ++/+++8,9
Copper low (M1) + ---- ----
Liquid lime sulfur8 low (M2) ---- ---- Dormant +/- Delayed Dormant +
Rating: ++++ = excellent and consistent; +++ = good and reliable; ++ = moderate and variable; + = limited and/or erratic; +/- = minimal and often ineffective; ---- = ineffective, and ND = no data
1 Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions. 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 Field resistance of Alternaria spp. to Abound and to other strobilurin fungicides (Gem and Cabrio) is widespread in pistachio orchards.
3 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/season.
4 Resistance to the SDHI (succinate dehydrogenase inhibitor) boscalid has been detected in high levels (80-90%) in some orchards; Pristine should not be applied if resistance to this fungicide is detected in an orchard. Cross-resistance of SDHI fungicides (FRAC Group 7) may occur.
5 Do not apply Bumper/Tilt within 60 days of harvest, Quash within 25 days of harvest, or tebuconazole fungicides (Tebucon/Teb/Toledo/Viathon) within 35 days before harvest.
6 Under low and moderate disease pressure.
7 Registered for bloom treatment only.
8 Dormant treatments and/or delayed dormant
9 Tested only under low disease pressure.

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: 05/18