PEACH AND NECTARINE: FUNGICIDE EFFICACY - CONVENTIONAL

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**Not registered, label withdrawn or inactive in California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/Unigard, Chairman, Mentor, Penbotec/ Pyrimethanil, and Scholar/FDL.

¹ Code 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 Code number are suitable to alternate in a resistance management program. In California, make no more than one application of fungicides with mode-of-actions (MOA) with high resistance risk before rotating to a fungicide with a different MOA (Code number); for other fungicides, make no more than two consecutive applications before rotating to fungicide with a different MOA (Code number).

² Do not use fungicides with the same FRAC number and high resistance risk more than twice in one year.

³ Strains of Monilinia fructicola resistant to Topsin-M and T-Methyl are present in some peach and nectarine orchards. Resistant strains of the jacket rot fungus, Botrytis cinerea, and powdery mildew fungi have been reported in California on crops other than almond and stone fruits and may have the potential to develop in peach and nectarine with overuse of fungicides with similar chemistry. Sub-populations of both Monilinia spp. have been shown to be resistant to AP (FRAC 9) fungicides on prune in CA.

⁴ 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.

⁵ Blossom blight only; not registered for use after petal fall.

⁶ Oil is a "light" summer oil, 1-2% volume/volume.

⁷ High summer temperatures and relative humidity reduce efficacy.

⁸ Do not use after jacket (shuck) split.

⁹ Do not use in combination with or shortly before or after oil treatment.

¹⁰ Not effective if used as a dormant treatment.

¹¹ For use on peach only; not registered on nectarine.

¹² For shot hole management, dormant treatments with copper, ziram, and dodine are highly effective. Petal fall treatments should be used to complement the management program.

PEACH AND NECTARINE - FUNGICIDE EFFICACY - BIOCONTROLS AND NATURAL PRODUCTS

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.

¹ Organic treatments arranged by performance on brown rot.

² FRAC Codes are also provided as BM- or P-number codes. In general, sulfur compounds are fungicidal and may affect applications of fungal biocontrols (e.g., Botector); whereas copper may affect applications of bacterial biocontrols (e.g., Actinovate, Double Nickel 55, and Serenade). Rotations must consider these factors.

³ PM refers to powdery mildew.

PEACH AND NECTARINE: TREATMENT TIMING

Note: Not all indicated timings may be necessary for disease control.

Rating: 3 = most effective, 2 = moderately effective, 1 = least effective, and 0 = ineffective (ND=No data).

¹ Timing not exact; weather conditions determine need for treatment.

² Apply until pit hardening.

³ Treatment should be made before bud break and preferably before bud swell.

⁴ Dormant treatment with liquid lime sulfur.

⁵ Fall application before winter rains begin is the most important; additional spring sprays are seldom required but may be needed to protect the fruit if heavy persistent spring rains occur.

PEACH AND NECTARINE: SUGGESTED DISEASE MANAGEMENT PROGRAMS BY FRAC¹ CODES - CONVENTIONAL AND ORGANIC GROWERS

Note: Not all indicated timings may be necessary for disease control (see Treatment Timing Table). If treatments are needed based on weather monitoring or environmental monitoring models, suggested fungicide Codes are listed for each timing.

How to use this table:

1) Identify the disease(s) that need(s) to be managed. Know the disease history of the orchard, especially from the previous season.

2) Select one of the suggested fungicide Codes. Numbers separated by slashes are pre-mixtures, whereas numbers grouped by pluses are tank mixtures. If several diseases need to be managed, select a Code that is effective against all diseases. Refer to fungicide efficacy table for fungicides belonging to each FRAC Code. Code numbers are listed in numerical order within the suggested disease management program.

3) Rotate Codes for each application within a season and, if possible, use each Code only once per season, except for multi-site mode-of-action materials or natural products/biological controls (e.g., M2, BM 01, BM 02, NC, P).

¹ Code numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions (for more information, see http://www.frac.info/). Code numbers are listed in numerical order within the suggested disease management program. Fungicides with a different Code number are suitable to alternate in a resistance management program. Refer to the fungicide efficacy table for fungicides belonging to each FRAC Code.

² Efficacy of liquid lime sulfur in dormant applications has not been determined for powdery mildew. Use liquid lime sulfur in dormant applications and wettable sulfur at and after pre-bloom.

³ Strains of Monilinia fructicola resistant to Benlate (label withdrawn), Topsin-M, and T-Methyl are present in some California peach/nectarine orchards. Resistant strains of the jacket rot fungus, Botrytis cinerea, and powdery mildew fungi have been reported in California on crops other than almond and stone fruits and may have the potential to develop in peach/nectarine with overuse of fungicides with similar chemistry. Subpopulations of both Monilinia spp. have been shown to be resistant to AP (FRAC 9) fungicides on prune in CA.

⁴ Among the Code 3 fungicides, only Teb/Orius and Quash have some activity against Botrytis cinerea.

⁵ FRAC M1 - copper, M2 - sulfur, BM 01 - Natural products, BM 02 - Biological controls(Streptomyces lydicus - Actinovate AG, Bacillus pumilus - Sonata, Bacillus subtilis - Serenade, Aviv), or NC (potassium bicarbonate - Kaligreen).