APPLE AND PEAR: FUNGICIDE EFFICACY – CONVENTIONAL

APPLE AND PEAR: FUNGICIDE EFFICACY – BIOCONTROLS AND NATURAL PRODUCTS

APPLE AND PEAR: BACTERICIDE EFFICACY – CONVENTIONAL

APPLE AND PEAR: BACTERICIDE 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.

* Registration pending in California.

** Not registered, label withdrawn or inactive in California.

*** Postharvest fruit registrations in California include: Academy, Alumni/TBZ, BioSpectra/Cerafruta, 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 High resistance potential to trifloxystrobin for apple and pear scab pathogen populations.

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 per season. Cercobin is registered only on apples.

⁴ On pear, use only before white bud and after full bloom.

⁵ Labeled on apple only in California (SAR = systemic acquired resistance).

⁶ These materials show some efficacy and should be used in mixtures with antibiotics as a component of resistance management programs. Captan is registered on apples, whereas Dithane is registered on apples and pears.

⁷ Though copper may be effective for scab and blight control under low disease pressure, copper products may cause fruit scarring or russeting.

⁸ "Burns out" scab twig lesions when applied at delayed dormant and disrupts pseudothecial (or ascostroma) development when applied to leaves in fall. CAUTION: Lime Sulfur is incompatible with most other pesticides when used after budbreak. check before use. Sulfur products are also used to thin flowers because of their phytotoxicity and indirectly control fireblight.

⁹ In-season application eradicates powdery mildew.

¹⁰ Labeled on pear but not apple.

¹¹ Plantgrowth regulators (PGR) such as prohexadione calcium (Apogee) can be used in an integrated approach to reduce host susceptibility but do not have antibiotic activity against fire blight.

¹² Acibenzolar-S-methyl (FRAC P1) is a host plant defense or systemic acquired resistancc (SAR) inducer known to stimulate the salicylic acid pathway.

¹³ Biologicals: FRAC Codes are provided as BM-No. or P-No. codes. In general, sulfur compounds are fungicidal and may affect applications of fungal biocontrols (e.g., Blossom Protect); whereas copper may affect applications of bacterial biocontrols (e.g., Actinovate, Bloomtime Biological, Blight Ban, Double Nickel 55, and Serenade). Rotations must consider these factors.

¹⁴ Sanitizers such peroxyacetic acid (e.g., Oxidate, Zerotol, Perasan A) are oxidizers that act immediately on contact. They are neutralized rapidly by reducing agents and are non-persistent. Note: Zerotol is registered only on apple, but not on pears. Perasan A is for postharvest use in sanitizing fruit only.

¹⁵ Higher numbers of indicate higher phytotoxicity.

APPLE AND PEAR: TREATMENT TIMING

Rating: 3 = most effective, 2 = moderately effective, 1 = least effective, and 0 = ineffective

¹ Protection of early tissue is important. Additional applications should be made according to infection periods as determined by the Mills table.

² Disruption of pseudothecial (ascostroma) development (fall) and inactivation of overwintering twig lesions (delayed dormant); effects of these treatments on disease control is uncertain.

³ Early applications are most effective; additional applications are made if mildew continues.

⁴ Start management program at the beginning of bloom and continue through bloom including "rat-tail" bloom throughout spring. Several models are available for forecasting infection periods and treatment timing. Models include: Maryblyt, Cougar Blight, etc.

POME FRUIT: SUGGESTED DISEASE MANAGEMENT PROGRAMS BY FRAC¹ CODES - CONVENTIONAL AND ORGANIC GROWERS

Note: Not all indicated timings may be necessary for disease control; whereas additional applications may be necessary under favorable conditions for disease (see Treatment Timing Table). Suggested fungicide bactericide, biological, and natural product Codes are listed for each timing based on host phenology, weather monitoring, inoculum models, or environmental-disease forecasting models.

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 the 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 (e.g., M2) or natural products/biological controls (BM 01, BM 02, NC, P).

¹- Fixed copper (M1a) bactericides (e.g., Kocide, Badge, Nordox, and ChampION⁺⁺) may cause phytotoxicity (russetting) when applied after full bloom. Other copper products (M1b) with lower metallic copper equivalent (i.e., MCE) such as copper complexes (e.g., Cueva, Copper Count-N, etc.) and copper sulfate pentahydrate (e.g., CS-2005, Phyton 27AG, etc.) have been reported to be less phytotoxic with applications following bloom because of lower MCE (see specific registrant label concerning product rates and number of times each material can be applied during the growing season).

² - M2 fungicides (e.g., liquid lime sulfur) that are registered for scab control have been used to thin-flowers in Washington state (Section 24c label) with one to two applications between 20-and 80% full bloom and subsequently have reduced the total number of flowers and potential infections sites for fire blight (indirect effects on disease). No label is available in CA for this usage.

³ - Acibenzolar-S-methyl (FRAC P 01) is a host plant defense inducer known to stimulate the salicylic acid pathway.

⁴ - In general, sulfur compounds are fungicidal and may affect applications of fungal biocontrols (e.g., Blossom Protect); whereas copper may affect applications of bacterial biocontrols (e.g., Actinovate, Bloomtime Biological, Blight Ban, Double Nickel 55, and Serenade). Rotations must consider these factors.

⁵ - Plant growth regulators (PGR) such as prohexadione calcium (e.g., Apogee) reduce shoot growth and thus, indirectly reduce the number of infections sites for fire blight (indirect effects on disease).