Where control is needed, fungicides should be applied before rainfall, beginning at 3” shoot growth through fruit harvest. Although not specifically labeled for control of angular leaf scorch, mancozeb products applied according to label directions to control Phomopsis, black rot, and downy mildew have provided good control of the disease. Mancozeb is the active ingredient in Dithane F-45 Rainshield (liquid formulation) and Manzate Pro-Stick Fungicide (dispersible granules). The maximum allowance for all products containing mancozeb ranges from 18-19.2 lb of active ingredient per acre per season. At the maximum use rate, Dithane or Manzate Pro-Stick can be used up to six times per season, but not within 66 days of harvest. For applications at 3-5” shoot growth, apply 1.6 to 3.2 qt Dithane or 2-4 lb Manzate Pro-Stick; for applications at 10-12” shoot growth through the immediate pre-bloom spray, apply 2.4 to 3.2 qt Dithane or 3-4 lb Manzate Pro-Stick; for post-bloom application, apply 3.2 qt Dithane F-45 or 4 lb Manzate Pro-Stick. 66 day PHI, 24 hr REI for listed mancozeb products.

Pristine Fungicide is labeled for control of Angular Leaf Scorch, but due to the concern for development of powdery mildew and downy mildew resistance, use of Pristine and any other strobilurin (Group 11) fungicides should be limited to a maximum of two applications per year, and should be saved for the immediate pre-bloom stage or later when they are likely to be most beneficial. For further discussion of the use of Pristine, refer to: https://doubleavineyards.com/plant-diagnostic/problems/powdery-mildew/ and https://doubleavineyards.com/plant-diagnostic/problems/downy-mildew/.

Cultural practices used to reduce the incidence of anthracnose include planting varieties less susceptible to the disease, increasing air circulation in the vineyard, eliminating wild grapevines on hedgerows and near the vineyard, pruning and removing diseased canes from the vineyard during the dormant season, and covering diseased berries with soil by cultivation or with mulch.

Where control is needed, fungicides should be applied beginning as early as 1” shoot growth. Once infections have occurred the disease can continue to spread throughout the growing season.

Although not specifically labeled for control of anthracnose, mancozeb products (Dithane F-45 Rainshield, Manzate Pro-Stick Fungicide), captan products (Captan 50 Wettable Powder, Captan 80WDG, Captec 4L) and Ziram 76DF Fungicide applied according to label directions to control Phomopsis, black rot, and downy mildew are likely to provide adequate control of anthracnose as well. Refer to the treatment plan for control of phomopsis, black rot, and downy mildew when control of anthracnose is also needed.

The sterol inhibitor (Resistance Group Number 3) fungicides Rally 40WSP, Mettle 125ME Fungicide, and Revus Top are registered for control of anthracnose, but the total number of sterol inhibitor sprays should be limited to a maximum of three per year to delay or prevent the development of powdery mildew resistance to this group of fungicides. Mettle (active ingredient tetraconazole) can be applied as early as 1” shoot growth at 3 to 5 fl oz per acre with a maximum of 3 applications and 10 fl oz per season. Rally can be applied as early as 1” shoot growth at 3 to 5 oz per acre and can be applied up to 1.5 lb per season. Revus Top can be applied as early as 1” shoot growth at 7 fl oz per acre and up to 28 fl oz per season, making no more than 2 sequential applications before alternating to a fungicide with a different mode of action.  Do not use Revus Top on Concord, Concord Seedless, and Thomcord (causes injury). 14 day PHI, 24 hr REI for Rally 40WSP; 14 day PHI, 12 hr REI for Mettle 125ME Fungicide and Revus Top.

The strobIlurin fungicide Pristine Fungicide (Resistance Group 11) is registered for control of anthracnose with applications beginning prior to the onset of disease. Powdery mildew and downy mildew resistance to the strobIlurin fungicides has occurred in many vineyards following several years of repeated use. It is highly recommended that the combined use of all strobIlurin fungicides including Sovran and Pristine be limited to no more than 2 applications per season and rotated or alternated with unrelated fungicides. If the strobIlurin fungicides are included in effective management programs for powdery mildew and downy mildew, their use should be saved for the immediate pre-bloom or later sprays. For anthracnose control, apply Pristine at 8-12.5 oz per acre. Do not use Pristine on Concord or Noiret as it causes injury. Use with caution on Steuben, Rougeon, Worden, Fredonia, Niagara and related varieties where injury has occurred irregularly. 14 day PHI, 12 hr/5 day REI – see label for details.

Cultural practices used to reduce black rot inoculum include removing mummies from the vineyard and/or burying them around bud break by cultivating soil under the vines. Control is improved using canopy management practices that promote air circulation, speed drying of leaves and fruit, and improve spray penetration.

Mancozeb is the active ingredient in Dithane F-45 Rainshield (liquid formulation) and Manzate Pro-Stick Fungicide (dispersible granules). Mancozeb products are the backbone for black rot control in vineyards. They provide protectant control of black rot as well as anthracnose, downy mildew, Phomopsis, and angular leaf scorch, and are at low risk of developing resistance. The maximum allowance for all products containing mancozeb ranges from 18-19.2 lb of active ingredient per acre per season. At the maximum use rate, Dithane or Manzate Pro-Stick can be used up to six times per season, but not within 66 days of harvest. Mancozeb sprays for black rot should not be delayed beyond the immediate pre-bloom spray as the immediate pre-bloom through post-bloom periods are critical for control of black rot. Under severe pressure, such as serious black rot was present in the vineyard the previous year, and warm, wet conditions are anticipated prior to the next spray, applications should be started as early as 3-5” shoot growth. Mancozeb applications for other diseases such as Phomopsis and anthracnose might be warranted as early as 1” shoot growth. Once applications commence they should be continued on a 7-10 day schedule prior to bloom, and 10-14 days after bloom. Use the shorter spray intervals following periods of high rainfall. As a general rule of thumb, one half of a mancozeb product will be washed off following one inch of rain. For applications at 3-5” shoot growth, apply 1.6 to 3.2 qt Dithane or 2-4 lb Manzate Pro-Stick. For applications at 10-12” shoot growth through the immediate pre-bloom spray, apply 2.4 to 3.2 qt Dithane or 3-4 lb Manzate Pro-Stick. For post-bloom application, apply 3.2 qt Dithane or 4 lb Manzate Pro-Stick.

Ziram 76DF Fungicide provides protectant control of black rot and Phomopsis, and suppression of downy mildew with low risk of disease resistance development. Ziram is similar to mancozeb products for control of black rot and Phomopsis, but less effective than mancozeb for control of downy mildew. Ziram can be used from 6” shoot growth until 21 days to harvest with a maximum 24 lb per acre per season; hence, Ziram is most useful where applications for control of black rot are needed within the 66 day PHI requirement for mancozeb products, or after the maximum seasonal use rate of mancozeb has been reached. Apply 3-4 lb Ziram for applications prior to bloom, and 4 lb Ziram for post-bloom applications. 21 day PHI, 48 hr REI.

Rally 40WSP, Mettle 125ME Fungicide, the difenoconazole portion of Revus Top, and the tebuconazole products TebuStar 45WSP (water soluble packets), Amtide Tebuconazole 45WDG Fungicide (water dispersible granules) and Orius 20 AQ (liquid formulation) are fungicides with similar chemistry (DMI or sterol inhibitor fungicides, Resistance Group Number 3) that provide control of black rot and powdery mildew, and in some cases are labeled for control of anthracnose. All the sterol inhibitor (SI) fungicides provide limited (several days) protective activity against black rot and are also effective when applied after the start of an infection period (typically 3-7 days). Protective activity of sprays for black rot control can be extended by tank-mixing with mancozeb. Powdery mildew resistance to the SI fungicides is widespread where the products have been previously used, so it is recommended that the combined use of all SI fungicide products is limited to a maximum of three times per season. For control of black rot, applications of the SI fungicides can begin as early as 3-5” shoot growth. Mancozeb products and Ziram also provide excellent protective control of black rot and are better choices for black rot control at the 3-5” stage if powdery mildew control is not needed. For applications prior to the immediate pre-bloom spray, apply 3-4 oz Rally or 3-5 fl oz Mettle or 7 fl oz Revus Top or 3-4 oz TebuStar or 8.6 fl oz Orius 20 AQ. For immediate pre-bloom or later applications, apply 4-5 oz Rally or 5 fl oz Mettle or 7 fl oz Revus Top or 4 oz TebuStar or 8.6 fl oz Orius. Do not use Revus Top on Concord, Concord Seedless, and Thomcord (causes injury) and use caution when applying on V. labrusca, V. labrusca hybrids, and other non-vinifera hybrids where sensitivity is not known – the use of Revus Top by itself or in tank mixtures with materials that may increase uptake (adjuvants, foliar fertilizers) may result in leaf burning or other phytotoxic effects. 14 day PHI for all SI products listed; 12 hr REI for all SI products listed, except 24 hr REI for Rally 40WSP.

Abound Flowable Fungicide and the pyraclostrobin component of Pristine Fungicide are fungicides with similar chemistry (strobIlurin fungicides, Resistance Group Number 11) that provide control of black rot, powdery mildew, downy mildew and Phomopsis. Pristine also controls Botrytis, while Abound provides suppression only. Pristine is also registered for control of anthracnose. Black rot control with Abound and Pristine is primarily protective with only limited post-infection activity. Although labeled for use starting at the 3-5” shoot growth stage, Abound and Pristine should be saved for the immediate pre-bloom or later sprays. Powdery mildew and downy mildew resistance to the strobIlurin fungicides has occurred in many vineyards following several years of repeated use. It is highly recommended that the combined use of all strobIlurin fungicides including Abound and Pristine be limited to no more than 2 applications per season and rotated or alternated with unrelated fungicides. For black rot control, apply 10-15.5 fl oz Abound or 8-12.5 oz Pristine. Higher rates may be needed for control of other diseases. Do not use Pristine on Concord or Noiret as it causes injury. Use with caution on Steuben, Rougeon, Worden, Fredonia, Niagara and related varieties where injury has occurred irregularly. 14 day PHI, 4 hr REI for Abound Flowable Fungicide; 14 day PHI, 12 hr/5 day REI for Pristine Fungicide – see label for details.

IMPORTANT NOTE: Abound is EXTREMELY phytotoxic to certain apple varieties. Do not spray Abound where spray drift may reach apple trees. Do not use spray equipment which has been previously used to apply Abound to spray apple trees, as even trace amounts can cause unacceptable phytotoxicity to certain apple and crabapple varieties.

The timing of fungicide sprays depends on seasonal weather patterns. Potential timings of sprays include late bloom, pre-bunch close, verasion, and pre-harvest. All Botrytis fungicides have the potential for developing disease resistance. Effective fungicide programs use a rotation among effective chemistries including Pristine Fungicide (Resistance Group Numbers 7 and 11), Elevate 50WDG Fungicide (Resistance Group Number 17), Rovral Brand 4 Flowable Fungicide (Resistance Group Number 2), and Vangard WG Fungicide (Resistance Group Number 9). Switch 62.5WG is a combination product containing the same active ingredient in Vangard, plus an unrelated, Resistance Group 12 fungicide. Pristine controls other important diseases while the other products are only used to control Botrytis. While pesticide labels may permit up to 3 applications per year, it is highly recommended that applications of any specific Resistance Group fungicides be limited to one or two applications per season in rotation with other Botrytis fungicides.

Pristine Fungicide is a combination fungicide containing pyraclostrobin (Resistance Group 11) and boscalid (Resistance Group 17), both providing activity against Botrytis with a high risk of disease resistance development against this disease. Pristine also has activity against downy mildew, powdery mildew, black rot, anthracnose, Phomopsis, and “summer rots”, but powdery mildew and downy mildew resistance is well-documented where Pristine or other Resistance Group 17 fungicides have been applied for many years. Wayne Wilcox at Cornell indicates Botrytis control with Pristine is fair when used at 8 to 10.5 oz. per acre, good when used at 12.5 oz per acre, and very good to excellent when used at 19 oz per acre.   14 day PHI, 12 hr/5 day REI – see label for details.

Rovral Brand 4 Flowable Fungicide is very effective against Botrytis where disease resistance has not developed. It provides protectant, post-infection, and anti-sporulant activity with a high risk of disease resistance development. Apply Rovral at 1.5 to 2 pint per acre in a minimum of 50 gallons per acre, aiming the spray at the fruit zone. Addition of non-ionic surfactant or oil may improve performance. Spray solution should have a pH of 5-7; use a buffer if necessary as some chemical breakdown is likely to occur especially if spray solution is alkaline (pH above 7). Four applications are permitted by the label but it is highly recommended to limit applications of Rovral to one per season and make at least one application per season of an unrelated fungicide with good Botrytis activity. 7 day PHI, 48 hr REI.

Elevate 50 WDG is very effective against Botrytis, it provides protectant and post-infection activity against Botrytis with a moderate risk of disease resistance development and also provides modest suppression of powdery mildew. Apply Elevate at 1 lb per acre in at least 50 gallons per acre, aiming the spray at the fruit zone. Use in a rotational program with other Botrytis fungicides. Do not apply more than 2 consecutive applications of Elevate before switching to another effective Botrytis fungicide, and do not apply more than 3 lb Elevate per season. 0 day PHI, 12 hr REI.

Vangard WG Fungicide is very effective against Botrytis where disease resistance has not developed, it provides protectant, post-infection, and anti-sporulant activity with a moderate risk of disease resistance development. Apply Vangard at 10 oz per acre, aiming the spray at the fruit zone. Use in a rotational program with other unrelated Botrytis fungicides. 7 day PHI, 12 hr REI.