Comments: Azoxystrobin (the active ingredient of Abound; also formulated as Heritage for use on turfgrass and Quadris for use on vegetables) was the first registered compound in the strobilurin (or "QoI") group of fungicides. It has provided excellent control of both powdery and downy mildew, very good control of black rot, and fair control of Phomopsis and Botrytis. However, the powdery mildew fungus has developed resistance to the strobilurin fungicides in multiple V. vinifera vineyards and some hybrid blocks, resulting in poor control of the disease where this has occurred. Resistance to the strobilurins by the downy mildew fungus has been widespread in Europe since the early 2000’s, has been documented as the cause of DM control failures in numerous vineyards in the mid-Atlantic and southern regions of the U.S., and recently has been suspected in some NY vineyards as well. Abound is absorbed into the waxy cuticle of the leaves and fruit (hence, it is relatively resistant to wash-off) but works primarily in a protectant mode; that is, it is most effective when present before an infection period occurs. However, it does have very limited post-infection activity against downy mildew and black rot and modest post-infection activity against powdery mildew. Also, it can limit disease spread by suppressing the production of new spores when applied post-infection, even though other symptoms may develop. Abound is labeled for use at 10–14 day intervals at a rate of 11.0 to 15.4 fl oz/A of the 2SC formulation. ABOUND IS LABELED FOR APPLICATION WITH GROUND EQUIPMENT ONLY, AND CANNOT BE APPLIED WITH AIRBLAST EQUIPMENT IN CERTAIN TOWNSHIPS AND BOROUGHS OF ERIE COUNTY, PA. It has a 4-hour reentry interval and may be applied to within 14 days of harvest.

CAUTION: Abound is extremely phytotoxic to many apple cultivars, especially McIntosh and its relatives (e.g., Cortland, Empire, Ben Davis). Severe injury and defoliation can occur if an Abound spray drifts onto such trees, or if these trees are sprayed with equipment that was used previously to apply Abound. To avoid such injury, (a) follow all precautions to avoid spray drift in the vicinity of apple orchards; and (b) do not make applications to apple trees with sprayers that have been used to apply Abound.

resistance warning: Powdery mildew resistance to the strobilurin fungicides (Abound, Flint, Sovran, the pyraclostrobin component of Pristine) has occurred in multiple V. vinifera and certain hybrid vineyards in the Finger Lakes region and on Long Island, sometimes resulting in significant crop loss. When such resistance occurs, none of the strobilurin fungicides will provide commercial control of powdery mildew, and they must be tank-mixed with an effective rate of an unrelated fungicide to avoid crop loss. Pristine, a product that combines a strobilurin fungicide (pyraclostrobin) with an unrelated material (boscalid), has provided good control of strobilurin-resistant powdery mildew populations. However, this control comes only from the boscalid component, which also is at risk for resistance development; hence Pristine also should be used sparingly and with caution where problems with strobilurins have been encountered. Furthermore, note that the boscalid component of Pristine provides no control of downy mildew, so it will not help control the spread of this disease should DM resistance to the strobilurins arise, as it has in the mid-Atlantic and southern regions of the U.S. and is suspected to have begun in NY as well. Where still effective, it is critical to use the strobilurins in a manner that minimizes the probability or speed of future resistance development. Make no more than two applications of any strobilurin product per year. Never use the strobilurins as the only fungicide group for control of powdery or downy mildew throughout the season. Always rotate them with an unrelated fungicide, even on varieties receiving a minimal number of fungicide sprays per season. Be sure to use appropriate labeled rates and spray intervals and assure thorough spray coverage. On varieties highly susceptible to powdery mildew, tank-mixing sulfur with the strobilurin fungicides will give an extra measure of protection at a relatively low cost (unless sulfur sensitive), as will the inclusion of boscalid as the non-strobilurin component of Pristine.

ADAMENT 50WG (50% tebuconazole + 50% trifloxystrobin) – read the label

Signal word: CAUTION

Medical emergency: (800) 334-7577

Chemical family: sterol inhibitor [DMI subgroup] + strobilurin [QoI]

Resistance risk: high

Physical mode of action: protectant, post-infection, antisporulant,

Selected use: powdery mildew, black rot, Botrytis, Phomopsis

Comments: Adament is a combination product containing roughly equal amounts of tebuconazole (ΔElite) and triflozystrobin (Flint); 2 oz of Adament contains the same amount of active ingredient as 1 oz of ΔElite + 1 oz of Flint. Thus, at the rates of 3 oz/A (14-day intervals) or 4 oz/A (21-day intervals) labeled for control of powdery mildew, Adament will provide the equivalent of 1.5 or 2.0 oz per acre, respectively, of both ΔElite and Flint. In vineyards where powdery mildew has become resistant to the strobilurin fungicides (e.g., Flint), this low rate of tebuconazole (ΔElite) is unlikely to provide adequate control of the disease, particularly in those with a long history of sterol inhibitor use; however, in vineyards where the strobilurins are still effective, the tebuconazole should provide modest help in slowing the onset of resistance development. Although it has not been tested in New York, Adament should provide very good to excellent control of Botrytis and black rot, and adequate control of Phomopsis, at the rates labeled against those diseases. Flint has weak activity against downy mildew and ΔElite has none; hence, Adament is not labeled for control of this disease.

CAUTION: Do not use on Concord grapes, due to the danger of plant injury from the Flint component.

ARMICARB 100 85WP (potassium bicarbonate) – read the label

Signal word: CAUTION

Medical emergency: (800) 424-9300

Chemical family: potassium salt

Resistance risk: low

Physical mode of action: post-infection, antisporulant, limited eradicant; NO protection

Selected use: powdery mildew

Comments: In New York trials, Armicarb 100 and Kaligreen (another potassium bicarbonate product) have shown activity very similar to that of Nutrol, a different potassium salt: fair control of powdery mildew but NO control of other diseases, although many are listed on the labels. It is assumed that the bicarbonates exert this control through the same physical modes of action as demonstrated for Nutrol (post-infection, antisporulant, and limited eradicant activity, but NO protective activity); however, this has not been proved.

CAPTAN 50WP, CAPTAN 80WDG, CAPTEC 4L

(captan) - read the label

Signal word: DANGER

Medical emergency: (800) 858-7378 (Captan), (866)303-6952 (Captec)

Chemical family: phthalimides

Resistance risk: low

Physical mode of action: protectant

Selected uses: Phomopsis cane and leaf spot, downy mildew, “summer rots”

Comments: REIs vary between products. Consult the label of the particular formulation you’re using. Do not apply more than 24 lb/A/season of Captan 50WP or more than 15 lb/A/ season of Captan 80WDG. It is illegal to apply Captan “during, with, or following” a spray of JMS Stylet Oil (danger of plant injury). There is also a danger if the oil is applied within 10 days after a Captan spray. Lime should not be used with Captan, or fungicide activity may be reduced. Captan may also cause plant injury if applied with or near other oils or products that cause uptake into the leaves and fruit (e.g., liquid insecticides, some surfactants). The use of Captan is not permitted by certain processors. Check with your processor before applying Captan.

COPPER COMPOUNDS (several formulations) - read the label

Signal word: CAUTION

Medical emergency: read the label

Chemical family: none (a basic element)

Resistance risk: low

Physical mode of action: protectant

Selected uses: downy mildew; some powdery mildew; modest black rot

Comments: Coppers provide adequate control of powdery mildew on moderately resistant varieties such as Concord; they should not be relied upon for V. vinifera and other highly susceptible varieties, although they will provide some suppression. CAUTION: Lime, typically applied with commercial copper formulations to reduce the chance of injury, should not be used with Captan, Ferbam Granuflo, *Imidan, or Sevin. Do not use copper on any variety unless the tolerance to copper injury is known (see Table 3.1.2 for varietal sensitivity). Copper applied under slow-drying conditions (cool or very humid) may cause injury even to some otherwise tolerant varieties.

ELEVATE 50WDG (fenhexamid) - read the label

Signal word: CAUTION

Medical emergency: (866) 303-6952

Chemical family: hydroxyanilide

Resistance risk: moderate

Physical mode of action: protectant, post-infection

Selected use: Botrytis bunch rot

Comments: Elevate is very effective against Botrytis. It also provides modest suppression of powdery mildew, but will not provide adequate control of this disease when used alone. Elevate is not related to any grape fungicide currently registered in North America; thus, it is useful in rotational programs designed to limit the risk of developing resistance to other Botrytis fungicides. It has a 12-hr restricted entry interval and a 0-day preharvest restriction.

ΔELITE 45 DF (tebuconazole) - read the label

Signal word: WARNING

Medical emergency: (800) 334-7577

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant

Selected uses: black rot, powdery mildew

Comments: At the labeled rate of 4 oz/A, ΔElite has activity against both black rot and powdery mildew that is virtually identical to that of Rally (^Nova) at the same rate. Do not apply at less than 7- or more than 14-day intervals, nor within 14 days of harvest.

Generic formulations: The patent on tebuconazole has expired, and several manufacturers are now formulating products other than ΔElite that contain this same active ingredient. However, ΔOrius 45DF (and 45WP) are the only tebuconazole products that have provided efficacy comparable to ΔElite in tests conducted by Cornell.

resistance warning: Powdery mildew resistance to the DMI fungicides (Bayleton, ΔElite, ^Mettle, Rally (^Nova), ΔOrius, *Procure, Rubigan, Vintage) is a common problem throughout the world, including New York and Pennsylvania. Although these fungicides continue to provide significant commercial control in most vineyards (except Bayleton, which no longer is recommended), they generally are less active than they were in the past and should not be relied upon as the primary tool for powdery mildew management. Nevertheless, the DMI fungicides will continue to be valuable in rotational programs with other powdery mildew fungicides, so it is important to implement four basic resistance management strategies to maintain their usefulness:

· limit the total number of DMI sprays to a maximum of three per year

· maintain full recommended rates on the vine (i.e., full rates in the tank PLUS good spray coverage)

· do not use the DMIs if more than a very modest amount of powdery mildew is present (i.e., use prebloom or to maintain a clean vineyard postbloom)

· do not exceed 14-day spray intervals, even when labels allow it - most of these labels were written years ago, when the fungicides were more active than they are now.

ENDURA 70 WG (boscalid) - read the label

Signal word: CAUTION

Medical emergency: (800) 832-4357

Chemical family: carboxamide

Resistance risk: moderate

Physical mode of action: protectant, post-infection; antisporulant activity probable but not yet demonstrated

Selected uses: powdery mildew, Botrytis

Comments: Boscalid is one of the two fungicidal components of the product, Pristine (the other component is pyraclostrobin, a strobilurin fungicide). As a solo product (not in mixture), boscalid is sold under the trade name Endura. It is unrelated to any other currently registered grape fungicide, so is useful as a rotational or tank-mix partner in a resistance-management program for powdery mildew and Botrytis control. However, note that Endura also is at risk for resistance development, so its use should be limited to a maximum of two applications per year and it should be used only in rotation or in tank-mix combinations with unrelated materials. Although it has excellent activity against both powdery mildew and Botrytis, note that higher rates are need for Botrytis control (8 oz/A) than for powdery mildew control (4.5 oz/A). Note also that Pristine used at the rate of 19 oz/A recommended for Botrytis control provides the same amount of boscalid as 6.8 oz of Endura, and in field trials this rate of Pristine has given control of Botrytis equivalent to 8 oz/A of Endura (the pyraclostrobin component of Pristine also provides modest Botrytis control). Endura has a 12-hr re-entry interval and a 14-day preharvest interval.

FERBAM GRANUFLO (ferbam) - read the label

Signal word: CAUTION

Medical emergency: (800) 424-9300

Chemical family: dimethyldithiocarbamate

Resistance risk: low

Physical mode of action: protectant

Selected use: black rot

Comments: Do not make more than three applications per season. Do not apply within 7 days of harvest. Fixed copper formulations and lime should not be used with Ferbam Granuflo. Ferbam Granuflo will provide suppression of downy mildew when used for control of black rot, but it should not be relied upon for highly susceptible varieties.

FLINT 50 WG (trifloxystrobin) - read the label

Signal word: CAUTION

Medical emergency: (800) 334-7577

Chemical family: strobilurin [QoI]

Resistance risk: high

Physical mode of action: protectant, variable but limited post-infection, antisporulant

Selected uses: black rot, powdery mildew, Botrytis, “summer rots”

Comments: Flint is a strobilurin fungicide, chemically related to Abound and Sovran (and to one component of Pristine). It has provided outstanding activity against powdery mildew where resistance to the strobilurins is not present. However, the powdery mildew fungus has developed resistance to the strobilurin fungicides in multiple V. vinifera vineyards, resulting in poor control of this disease in the affected blocks (see below). Like the other strobilurins, Flint is very good against black rot and fair against Phomopsis, but it is weak against downy mildew. Unlike Abound and Sovran, it also is labeled for control of Botrytis (although at a rate of 3.0 oz/A versus 1.5-2.0 oz/A for powdery mildew and black rot), and has provided very good results in multiple New York trials. Flint has a 12-hr restricted entry interval and a 14-day preharvest interval. The active ingredient in Flint (trifloxystrobin) is also sold in a pre pack mixture with tebuconazole (active ingredient in ∆Elite) as the product Adament.

CAUTION: Flint is phytotoxic (leaf burn) when sprayed onto Concord grapes—do not use on this variety. Flint reportedly is not phytotoxic on Niagara or any other variety except Concord.

resistance warning: Powdery mildew resistance to the strobilurin fungicides (Abound, Flint, Sovran and the pyraclostrobin component of Pristine) has occurred in multiple V. vinifera and certain hybrid vineyards in the Finger Lakes region and on Long Island, sometimes resulting in significant crop loss. When such resistance occurs, none of the strobilurin fungicides will provide commercial control of powdery mildew, and they must be tank-mixed with an effective rate of an unrelated fungicide to avoid crop loss. Pristine, a product that combines a strobilurin fungicide (pyraclostrobin) with an unrelated material (boscalid), has provided good control of strobilurin-resistant powdery mildew populations. However, this control comes only from the boscalid component under such conditions, which also is at risk for resistance development, hence Pristine also should be used sparingly and with caution where problems with strobilurins have been encountered. Furthermore, note that the boscalid component of Pristine provides no control of downy mildew so will not help control the spread of this disease should resistance arise, as it has in the mid-Atlantic and southern regions of the U.S. and is suspected to have begun in NY as well. Where still effective, it is critical to use the strobilurins in a manner that minimizes the probability or speed of future resistance development. Make no more than two applications of any strobilurin product per year. Never use the strobilurins as the only fungicide group for control of powdery or downy mildew throughout the season. Always rotate them with an unrelated fungicide, even on varieties receiving a minimal number of fungicide sprays per season. Be sure to use appropriate labeled rates and spray intervals and assure thorough spray coverage. On varieties highly susceptible to powdery mildew, tank-mixing sulfur with the strobilurin fungicides will give an extra measure of protection, as will the use of boscalid as a component of Pristine.

*^NYGAVEL 75DF (zoxamide + mancozeb) - read the label

Signal word: CAUTION

Medical emergency: (888) 478-0798

Chemical family: benzamide + EBDC

Resistance risk: moderate (zoxamide) + low (mancozeb)

Mode of action: protectant, post-infection, antisporulant (?)

Selected uses: downy mildew

Comments: *^NYGavel is a product that combines two active ingredients: (i) zoxamide, a downy mildew-specific fungicide unrelated to any other materials on the market; and (ii) mancozeb. When applied at the labeled rate of 2.0-2.5 lb/A, it provides the same amount of mancozeb as 1.8-2.2 lb of standard 75DF formulations of other mancozeb products such as Dithane, Penncozeb, etc. Thus, for control of diseases other than downy mildew, *^NYGavel should be applied with sufficient quantities of another mancozeb product to provide a dosage equivalent to 3-4 lb/A of the 75DF formulations of such products. In a limited number of trials, *^NYGavel has provided fair to good control of downy mildew when applied at 14-day intervals.

JMS STYLET OIL - read the label

Signal word: CAUTION

Medical emergency: (866) 778-9538

Chemical family: petroleum oil

Resistance risk: low

Physical mode of action: post-infection, antisporulant, eradicant, modest protectant

Selected uses: Powdery mildew, spider mites – see insecticides

Comments: Effective against powdery mildew when used at 1 to 2 percent solution in high-volume applications at 10- to 14-day intervals. Labeled for control of, but not effective against, Botrytis. Do not concentrate beyond 2 percent (2 gal/100 gal water), regardless of gallonage used. There are potential compatibility problems with various nutrient sprays and other pesticides, including Captan, *Vendex, and sulfur, and legal restrictions on their use with this product; check the label for details. JMS Stylet Oil provides significant eradicant activity against existing infections. However, this product works strictly by contact, hence THOROUGH spray coverage is MANDATORY. Recent research shows that Stylet Oil has moderate protective activity against new infections for 3 to 7 days following an application, but much of this is lost after a 1/4-inch rain, presumably due to wash-off. Both “conventional” and “organically-approved” formulations are available and appear to be comparably effective.

cautions: (1) Do not spray oils while temperatures are very high (above 85-90°F), or burning may occur. (2) Oils remove the waxy “bloom” from berry surfaces, so should not be used within 60 days of harvest on fruit to be sold for the fresh market.

note: In many, but not all controlled tests, two or more applications of JMS Stylet Oil near veraison have resulted in a modest but consistent lowering of Brix values (1° to 2°) at harvest. In contrast, applications before this period generally have had no effect on Brix values.

KALIGREEN 82 SP

(potassium bicarbonate) - read the label

Signal word: CAUTION

Medical emergency: (800) 858-7378

Chemical family: potassium salt

Resistance risk: low

Physical mode of action: post-infection, antisporulant, limited eradicant

Selected uses: powdery mildew

Comments: Kaligreen contains the same active ingredient as Armicarb 100 and Milstop, and works in a manner similar to those products and Nutrol, another potassium salt: fair control of powdery mildew but NO control of other diseases, although many are listed on the labels. As with all potassium salts, control is provided by contact action, so thorough spray coverage is mandatory and there is no residual activity. In trials conducted over several years in New York, all of the potassium salt products have provided similar levels of control when used at their labeled rates.

MANZATE 75DF, DITHANE M-45, *^NYDITHANE DF RAINSHIELD, DITHANE F-45 RAINSHIELD, PENNCOZEB 75DF (mancozeb) - read the label

Signal word: CAUTION

Medical emergency: Dithane: (800) 992-5994, Manzate: (888)324-7598, Penncozeb: (303) 623-5716

Chemical family: ethylenebisdithiocarbamate (EBDC)

Resistance risk: low

Physical mode of action: protectant

Selected uses: black rot, downy mildew, Phomopsis cane and leaf spot, angular leaf scorch

Comments: Do not enter treated area within 24 hours of application unless proper protective clothing is worn. The maximum allowance for these materials is 24 lb/A/season. Do not apply within 66 days of harvest. The use of these fungicides may be permitted only prior to bloom by certain processors. Check with your processor before applying these pesticides.

^METTLE (tetraconazole) - read the label

Signal word: CAUTION

Medical emergency: 800-424-9300

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant

Selected use: powdery mildew, black rot

Comments: ^Mettle is a newly-available DMI fungicide, similar to but chemically different from the existing materials listed below. In multiple NY tests, it has been equivalent to or slightly more effective than these other products when applied at its maximum rate of 5 fl oz/A. In Ohio tests, it has also provided excellent control of black rot. It has a 12-hr REI and a 14-day PHI.

resistance warning: Powdery mildew resistance to the DMI fungicides (Bayleton, ΔElite, Rally (Nova), ΔOrius, *Procure, Rubigan, and Vintage) is a common problem throughout the world, including New York and Pennsylvania. Although these fungicides continue to provide significant commercial control in most vineyards (except Bayleton, which no longer is recommended), they are less active than they were in the past and should not be relied upon as the primary tool for powdery mildew management. Nevertheless, the DMI fungicides will continue to be valuable in rotational programs with other powdery mildew fungicides, so it is important to implement four basic resistance management strategies to maintain their usefulness:

· limit the total number of DMI sprays to a maximum of three per year

· maintain full recommended rates on the vine (i.e., full rates in the tank PLUS good spray coverage)

· do not use the DMIs if more than a very modest amount of powdery mildew is present (i.e., use prebloom or to maintain a clean vineyard postbloom)

· do not exceed 14-day spray intervals, even when labels allow it - these labels were written years ago, when the fungicides were more active than they are now.

^NOVA (myclobutanil) - see Rally

NOTE: Rally is the relatively new name for ^Nova in the eastern U.S. The two products and label use directions are identical – the only differences between the two are the product name and a single digit in the EPA registration number. ^Nova remains a legal product to use according to label directions for those with older material still on hand, but it is no longer manufactured under that name.

NUTROL (dihydrogen potassium phosphate = monopotassium phosphate) - read the label

Signal word: CAUTION

Medical emergency: (800)424-9300

Chemical family: potassium salt

Resistance risk: low

Physical mode of action: post-infection, antisporulant, limited eradicant

Selected use: powdery mildew

Comments: Monopotassium phosphate (potassium dihydrogen phosphate) is a fertilizer (K and P) that can be applied to both the soil and foliage. Nutrol is a monopotassium phosphate product that also provides moderate control of powdery mildew when sprayed onto fruit and foliage, and is registered for that use. It provides no protective activity but significant post-infection activity when applied up to one week after infection. However, it has been relatively ineffective at eradicating well-established powdery mildew infections. It is most effective when used in alternation or tank mixes with traditional powdery mildew fungicides, or with short (7-day) spray intervals if applied two or more times in sequence. NOTE: For best results, Nutrol should be applied with a nonionic surfactant to increase coverage of the leaf and fruit surfaces, since it is not already formulated with one.

ΔORIUS 45DF, 45WP (tebuconazole) - read the label

Signal word: WARNING

Medical emergency: (877) 250-9291

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant,

Selected uses: black rot, powdery mildew

Comments: ΔOrius contains the same active ingredient, in the same concentration, as ΔElite. In multiple tests in NY, the two products have provided comparable control when used at the same label rate of 4 oz/A. Refer to the entry for ΔELITE for additional information such as RESISTANCE WARNING information.

PHOSTROL, PROPHYT (phosphorous acid = phosphonate = phosphite) - read the label

Signal word: CAUTION

Medical emergency: ProPhyt: (800) 424-9300, Phostrol (877) 325-1840

Chemical family: phosphorous acid (phosphonate, phosphite)

Resistance risk: moderate

Physical mode of action: moderate protectant, post-infection, antisporulant

Selected use: downy mildew

Comments: A number of products containing phosphorous acid (also called “phosphite” or “phosphonate”) are sold as nutritional supplements and “plant conditioners,” but only a few are registered for disease control on grapes; the two that have proven efficacy in NY are ProPhyt and Phostrol. In multiple trials, both products have provided very good to excellent control of downy mildew, but have not controlled any other grape disease. Although very active when applied up to 5-7 days after infection first occurs, their residual (protective) activity against infections occurring after application is limited; hence, spray intervals should not exceed 10 days during periods of wet weather. These products have a 4 hr re-entry interval, 0 day preharvest interval, and are exempt from residue tolerances (limits).

^PRESIDIO 4SC (fluopicolide) - read the label

Signal word: CAUTION

Medical emergency: (800) 892-0099

Chemical family: benzamide

Resistance risk: high (?)

Physical mode of action: protectant, post-infection, antisporulant (reputedly; few data available)

Selected uses: downy mildew

Comments: NOT LABELED IN NEW YORK STATE AT PRESS TIME – DO NOT USE IN NY UNTIL STATE REGISTRATION IS GRANTED. ^Presidio is a new fungicide that, on grapes, controls only downy mildew. In several field trials, it has been very effective for this purpose when used at the labeled rate of 3 to 4 fl oz/A. It is absorbed by plant tissues, and therefore is not subject to wash-off by rain. Such materials typically provide post-infection and anti-sporulant activity along with some residual protectant action; these properties are claimed for ^Presidio as well. ^Presidio is not related to any other fungicide currently registered on grapes, so is an option for use as a rotational component in a resistance management program. Due to its own risk of resistance development, the label (law) requires that ^Presidio be applied in tank mixture with another fungicide registered for downy mildew control.

PRISTINE 38WG (13% pyraclostrobin + 25% boscalid) - read the label

Signal word: CAUTION

Medical emergency: (800) 832-4357

Chemical family: strobilurin (QoI) + carboxamide

Resistance risk: high

Resistance risk: moderate (powdery mildew) to high (downy mildew)

Physical mode of action: protectant, selective post-infection (powdery mildew and some Botrytis), antisporulant

Selected uses: powdery mildew, downy mildew, black rot, Phomopsis, Botrytis, “summer rots”

Comments: Pristine contains two unrelated active ingredients, pyraclostrobin and boscalid. Pyraclostrobin is a strobilurin fungicide that provides excellent activity against downy mildew in vineyards where this disease has not yet developed resistance to the strobilurins, very good activity against black rot, fair to good (?) activity against Phomopsis, and fair activity against Botrytis (at higher rates). It also provides very good control of the “summer rot” diseases (bitter rot and ripe rot) that are common in more southerly regions, and provides some suppression of the “sour rot” complex. It also provides excellent control of powdery mildew in vineyards where resistance to the strobilurins has not yet developed. Boscalid (also sold as a solo product under the trade name, Endura) provides excellent control of powdery mildew, even in strobilurin-resistant sites, and fair to excellent control of Botrytis, depending on the rate used. Thus, Pristine has provided very good to excellent control of powdery mildew, downy mildew, and black rot; fair to good control of Phomopsis; and fair control of Botrytis when used at a rate of 8 to 10.5 oz/A. Botrytis control has generally been good at the highest “standard” label rate of 12.5 oz/A, and has consistently been very good to excellent in several trials when used at a rate of 19 oz/A. PRISTINE IS PHYTOTOXIC ON CONCORD AND NOIRET (NY73.0136.17), SO SHOULD NOT BE USED ON THESE VARIETIES. It should also be used with caution on Steuben and Rougeon, where injury has occurred irregularly. It has a 14-day preharvest interval and a usual 12-hour re-entry interval, regardless of rate used; however, the REI increases to 5 days if conducting cane tying, turning, or girdling operations on treated vines. NOTE: Product labels printed before mid-2007 are somewhat more restrictive at use rates above 12.5 oz/A; you must follow the label directions on the particular batch of product that is being used.

resistance warning: Powdery mildew resistance to the strobilurin fungicides (Abound, Flint, Sovran, and the pyraclostrobin component of Pristine) has occurred in multiple V. vinifera and certain hybrid vineyards in the Finger Lakes region and on Long Island, sometimes resulting in significant crop loss. When such resistance occurs, none of the strobilurin fungicides will provide commercial control of powdery mildew, and they must be tank-mixed with an unrelated, effective fungicide to avoid crop loss. Pristine has provided good control of strobilurin-resistant powdery mildew populations. However, this control comes only from the boscalid component of the product, which also is at risk for resistance development. Therefore, Pristine also should be used sparingly and with caution where problems with strobilurins have been encountered. Furthermore, the boscalid component of Pristine provides no control of downy mildew, so it will not help control the spread of this diseases should resistance arise, as it has in many vineyards across the mid-Atlantic and southern regions of the U.S. Typically, where powdery mildew resistance first appeared in NY vineyards, strobilurins had been applied a total of approximately 15 to 20 times since their introduction. Although other growers have made similar or greater numbers of applications without problem, especially when they have regularly tank-mixed the materials with other effective PM fungicides, this figure should serve as a rough "benchmark" to warn that the risk of resistance has increased within individual blocks once it has been reached. Where still effective, it is critical to use the strobilurins in a manner that minimizes the probability or speed of future resistance development. Make no more than two applications of any strobilurin product per year. Never use the strobilurins as the only fungicide group for control of powdery or downy mildew throughout the season. Always rotate them with an unrelated fungicide, even on varieties receiving a minimal number of fungicide sprays per season. Be sure to use appropriate labeled rates and spray intervals and assure thorough spray coverage. On varieties highly susceptible to powdery mildew, tank-mixing sulfur with Pristine will give an extra measure of protection against the development of this disease becoming resistant to both components of the product (unless sulfur-sensitive).

*PROCURE - read the label

Signal word: DANGER

Medical emergency: (203) 723-3670 or (800) 292-5898 (see label)

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: high

Mode of action: post-infection, antisporulant, limited protectant,

Selected use: powdery mildew

Comments: Do not enter treated area within 12 hours of application unless proper protective clothing is worn. Do not exceed 32 oz/A per season. *Procure is a sterol-inhibitor fungicide with good activity against powdery mildew, but it does not provide commercially acceptable control of black rot under moderately high disease pressure. It is labeled for use at 4–8 oz/A. Limited experience suggests that the 4 oz/A rate may be adequate before bloom, but at least 6 oz/A should be used after bloom. The usage rate should be adjusted according to varietal susceptibility, disease pressure, and the amount of foliage growth present. Intervals between sprays should not exceed 14 days.

resistance warning: Powdery mildew resistance to the DMI fungicides (Bayleton, ΔElite, Rally (^Nova), ^Mettle, ΔOrius, *Procure, Rubigan, and Vintage) is a common problem including New York and Pennsylvania. Although these fungicides continue to provide significant commercial control in most vineyards (except Bayleton, which no longer is recommended), they are less active than they were in the past and should not be relied upon as the primary tool for powdery mildew management. Nevertheless, the DMI fungicides will continue to be valuable in rotational programs with other powdery mildew fungicides, so it is important to implement four basic resistance management strategies to maintain their usefulness:

· limit the total number of DMI sprays to a maximum of three per year

· maintain full recommended rates on the vine (i.e., full rates in the tank PLUS good spray coverage)

· do not use the DMIs if more than a very modest amount of powdery mildew is present (i.e., use prebloom or to maintain a clean vineyard postbloom)

· do not exceed 14-day spray intervals, even when labels allow it - these labels were written years ago, when the fungicides were more active than they are now.

PURESPRAY (“GREEN” AND “^FOLIAR”)

- read the label

Signal word: CAUTION

Medical emergency: (403) 296-3000

Chemical family: petroleum oil

Resistance risk: low

Physical mode of action: post-infection, eradicant, some protectant

Selected use: powdery mildew

Comments: Both Purespray products (the “Green” formulation is approved for organic production) have provided good control of powdery mildew in several research trials conducted in NY. The oil is very similar to JMS Stylet Oil in composition and modes of activity, and has provided comparable results when used at the same rate. The precautions regarding pesticide compatibilities and potential Brix reductions, listed previously for JMS Stylet Oil, apply equally to the Purespray products.

QUINTEC 250SC (quinoxyfen) - read the label

Signal word: CAUTION

Medical emergency: (800) 992-5994

Chemical family: quinoline

Physical mode of action: protectant

Resistance risk: moderate

Selected use: powdery mildew

Comments: Quintec is the first fungicide in a new chemical family, the quinolines. It is unrelated to any other currently-registered grape fungicide, so it controls powdery mildew colonies that are resistant to other fungicides and is useful as a rotational partner in a resistance-management program. However, Quintec also is at risk for resistance development, so it should not be used more than three times per season and should always be used in rotation with other effective powdery mildew fungicides. Quintec does not provide control of any disease except powdery mildew. It is strictly a protectant fungicide that must be present before the powdery mildew fungus begins the infection process; it does not provide any post-infection or eradicative activity. Although the current label allows a wide range of use rates and spray intervals, we recommend a rate of 3-4 oz/A at no more than 14-day spray intervals. Quintec has a 12-hr re-entry interval and a 14-day preharvest interval.

RALLY 40WSP (myclobutanil) - read the label

NOTE: Rally is the new name for ^Nova in the eastern US. The two products and label use directions are identical, for the only differences between the two are the product name and a single digit in the EPA registration number. ^Nova remains a legal product to use according to label directions, but it will no longer be manufactured under that name.

Signal word: WARNING

Medical emergency: (800) 992-5994

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant,

Selected uses: black rot, powdery mildew

Comments: Do not exceed 14-day intervals between applications. The maximum allowance for Rally is 24 oz/A/season. Do not apply within 14 days of harvest. Rally should be sprayed out as soon as possible if it is tank-mixed with a copper compound. Periods of several hours or more in a solution with copper can reduce the effectiveness of Rally.

resistance warning: Powdery mildew resistance to the DMI fungicides (Bayleton, ΔElite, Rally (^Nova), ^Mettle, ΔOrius, *Procure, Rubigan, and Vintage) is a common problem throughout the world, including New York and Pennsylvania. Although these fungicides continue to provide significant commercial control in most vineyards (except Bayleton, which no longer is recommended), they are less active than they were in the past and should not be relied upon as the primary tool for powdery mildew management. Nevertheless, the DMI fungicides will continue to be valuable in rotational programs with other powdery mildew fungicides, so it’s important to implement four basic resistance management strategies to maintain their usefulness:

· limit the total number of DMI sprays to a maximum of three per year

· maintain full recommended rates on the vine (i.e., full rates in the tank PLUS good spray coverage)

· do not use the DMIs if more than a very modest amount of powdery mildew is present (i.e., use prebloom or to maintain a clean vineyard postbloom)

· do not exceed 14-day spray intervals, even when labels allow it - most of these labels were written years ago, when the fungicides were more active than they are now.

REVUS 2SC (mandipropamid) - read the label

Signal word: CAUTION

Medical emergency: (800) 888-8372

Chemical family: carboxylic acid amide (CAA)

Resistance risk: moderate

Physical mode of action: protectant, post-infection, antisporulant (reputedly; few data available)

Selected uses: downy mildew

Comments: Revus is a new fungicide that, on grapes, controls only downy mildew. It is absorbed by plant tissues, and therefore is not subject to wash-off by rain. Such materials typically provide post-infection and anti-sporulant activity along with some residual protectant action; these properties are claimed for Revus as well. Revus is not related to any other fungicide currently registered on grapes, so is an option for use as a rotational component in a resistance management program. It provided excellent control of downy mildew in both research trials and commercial usage during the very wet 2009 season.

RIDOMIL GOLD/COPPER (mefanoxam plus copper -hydroxide) - read the label

Signal word: WARNING

Medical emergency: (800) 888-8372

Chemical family: phenylamide plus elemental copper

Resistance risk: high

Physical mode of action: protectant, postinfection, antisporulant

Selected use: downy mildew

Comments: Not for use prebloom; if a prebloom application of Ridomil is desired, use Ridomil MZ. Ridomil is an outstanding fungicide against downy mildew, but the causal organism develops resistance to Ridomil very quickly when the product is used intensively, e.g., this fungicide became ineffective in the humid viticultural regions of Europe soon after its introduction many years ago. To reduce the risk of developing resistance, use no more than two applications of Ridomil per season (MZ and copper formulations combined), and do not attempt "rescue" treatments if an epidemic is in progress. Do not apply Ridomil Gold/Copper within 42 days of harvest; this is a shorter PHI than that for Ridomil Gold MZ, which has a 66-day PHI.

RIDOMIL GOLD MZ (mefanoxam plus mancozeb)

- read the label

Signal word: WARNING

Medical emergency: (800) 888-8372

Chemical family: phenylamide plus EDBC

Resistance risk: high

Physical mode of action: protectant, post-infection, antisporulant

Selected use: downy mildew

Comments: Do not use within 66 days of harvest (note that this is a longer PHI than that for Ridomil Gold/Copper, which has a 42 day PHI). At the labeled rate of 2.5 lb/A, Ridomil Gold MZ provides the same amount of mancozeb as standard products (e.g., Dithane, Manzate, Penncozeb) applied at 2 lb/A of their 75DF formulations. Thus, it will provide modest control of black rot and Phomopsis, but significantly less than the 3–4 lb/A rate of the standard mancozeb products. Therefore, it should be supplemented with additional mancozeb if good control of these diseases is necessary. The downy mildew organism develops resistance to Ridomil very quickly when it is used intensively, e.g., this fungicide became ineffective in the humid viticultural regions of Europe soon after its introduction many years ago. To reduce the risk of developing resistance, use no more than two applications of Ridomil per season (MZ and copper formulations combined), and do not attempt "rescue" treatments if an epidemic is in progress.

ROVRAL (iprodione) - read the label

Signal word: CAUTION

Medical emergency: (800) 334-7577

Chemical family: dicarboximide

Resistance risk: high

Physical mode of action: protectant, post-infection, antisporulant

Selected use: Botrytis bunch rot

Comments: Do not allow spray mixture to stand for prolonged periods, as some chemical breakdown may occur, particularly in water with a high pH. Addition of a nonionic surfactant (or oil) often improves results, particularly at lower rates. Do not enter the treated area within 48 hours of application unless proper protective clothing is worn. Do not apply within 7 days of harvest.

resistance warning: Resistance is common in European vineyards where Rovral and other related fungicides have been used for many years. Although there is little formal proof of Rovral resistance in the northeastern United States, there is strong circumstantial evidence for it in a number of vineyards with a long history of use. The registration of new, unrelated Botrytis fungicides (Elevate, Endura/Pristine, Flint, Scala, Vangard) has provided growers the opportunity to rotate these materials with each other and with Rovral, in order to reduce resistance development and maintain the usefulness of all of them. Such a rotational program is strongly recommended.

RUBIGAN (fenarimol) - read the label

Signal word: WARNING

Medical emergency: (888) 478-0789

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant

Selected use: powdery mildew

Comments: Labeled per-acre rates increase as the season progresses; exceeding recommended rates in the early season may cause foliar injury. Do not enter the treated area within 12 hours of application unless proper protective clothing is worn. Do not exceed 19 fl oz/A per season or apply within 21 days of harvest. Rubigan is a sterol inhibitor fungicide with good activity against powdery mildew, but it does not provide commercially acceptable control of black rot.

resistance warning: Powdery mildew resistance to the DMI fungicides (Bayleton, ΔElite, ^Mettle, Rally (^Nova), ΔOrius, *Procure, Rubigan, and Vintage) is a common problem throughout the world, including New York and Pennsylvania. Although these fungicides continue to provide significant commercial control in most vineyards (except Bayleton, which no longer is recommended), they are less active than they were in the past and should not be relied upon as the primary tool for powdery mildew management. Nevertheless, the DMI fungicides will continue to be valuable in rotational programs with other powdery mildew fungicides, so it is important to implement four basic resistance management strategies to maintain their usefulness:

· limit the total number of DMI sprays to a maximum of three per year

· maintain full recommended rates on the vine (i.e., full rates in the tank PLUS good spray coverage)

· do not use the DMIs if more than a very modest amount of powdery mildew is present (i.e., use prebloom or to maintain a clean vineyard postbloom)

· do not exceed 14-day spray intervals, even when labels allow it - most of these labels were written years ago, when the fungicides were more active than they are now.

SCALA (pyrimethanil) - read the label

Signal word: CAUTION

Medical emergency: (800) 334-7577

Chemical family: anilinopyriidine

Resistance risk: high

Physical mode of action: protectant, post-infection, antisporulant

Selected use: Botrytis bunch rot

Comments: Scala is an anilinopyrimidine (AP) fungicide that is very similar to Vangard in its activity and risk of resistance development. Should the Botrytis fungus develop resistance to one of these chemicals, it will also be resistant to the other. Consequently, rotating Vangard and Scala will NOT help delay resistance to either one. Therefore, make no more than two applications per season of any AP fungicide, and do not rely on this single chemical family for Botrytis control year after year.

SOVRAN 50WG (kresoxim-methyl) - read the label

Signal word: CAUTION

Medical emergency: (800) 832-4357

Chemical family: strobilurin [QoI]

Resistance risk: high

Physical mode of action: protectant, variable but limited post-infection, antisporulant

Selected uses: powdery mildew, black rot, downy mildew, Phomopsis

Comments: Sovran is a strobilurin fungicide, chemically related to Abound and Flint. It has provided excellent activity against powdery mildew. However, the powdery mildew fungus has recently developed resistance to the strobilurin fungicides in multiple V. vinifera vineyards, resulting in poor control of this disease in the affected blocks (see below). Like the other strobilurins, it is very good against black rot and fair against Phomopsis. Unlike Abound and Pristine, it is only fair against downy mildew. It is registered for “suppression” of Botrytis; a limited number of NY trials suggest that it is fair to good for this purpose. Sovran has a 12-hr restricted entry interval and a 14-day preharvest interval.

resistance warning: Powdery mildew resistance to the strobilurin fungicides (Abound, Flint, Sovran, and the pyraclostrobin component of Pristine) has occurred in multiple V. vinifera and certain hybrid vineyards in the Finger Lakes region and on Long Island, sometimes resulting in significant crop loss. When such resistance occurs, none of the strobilurin fungicides will provide commercial control of powdery mildew, and they must be tank-mixed with an effective rate of an unrelated fungicide to avoid crop loss. Pristine has provided good control of strobilurin-resistant powdery mildew populations. However, this control comes only from the boscalid component of the product, which also is at risk for resistance development. Therefore, Pristine also should be used sparingly and with caution where problems with strobilurins have been encountered. Furthermore, the boscalid component of Pristine provides no control of downy mildew so will not help control the spread of this disease should resistance arise, as it has in the mid-Atlantic and southern regions of the U.S., and is suspected to have begun in New York as well. Where still effective, it is critical to use the strobilurins in a manner that minimizes the probability or speed of future resistance development. Make no more than two applications of any strobilurin product per year. Never use the strobilurins as the only fungicide group for control of powdery or downy mildew throughout the season. Always rotate them with an unrelated fungicide, even on varieties receiving a minimal number of fungicide sprays per season. Be sure to use appropriate labeled rates and spray intervals and assure thorough spray coverage. On varieties highly susceptible to powdery mildew, tank-mixing sulfur with the strobilurin fungicides will give an extra measure of protection (unless sulfur-sensitive), as will the use of boscalid as a component of Pristine.

SULFUR (several formulations) - read the label

Signal word: CAUTION

Medical emergency: read the label

Chemical family: elemental sulfur

Resistance risk: low

Physical mode of action: protectant, post-infection, anti-sporulant, some eradicant

Selected use: powdery mildew

Comments: Do not enter treated area within 24 hours of application unless proper protective clothing is worn. Some Labrusca-type grapes (such as Concord) and red hybrids may be injured by sulfur (see Table 3.1.2 for varietal sensitivity). Sulfur activity is strongly influenced by formulation, by rate and frequency of application, and by weather. It generally is highly effective when applied at relatively high rates and short (7- to 10-day) spray intervals, but efficacy can decline as intervals increase and/or rates decrease. It is subject to wash-off, and reapplications may need to be more frequent after significant rainfall. Use with a "sticker" adjuvant appears to improve performance under high rainfall conditions, as does increasing the rate of product applied. Although "conventional wisdom" has long held that sulfur activity is reduced significantly at temps below 65°F, recent research suggests little to no effect of temperature on disease control when applied within the temperature range where powdery mildew is active. Do not apply sulfur within 14–21 days of a spray oil application (see oil product label).

TEBUZOL 45DF (tebuconazole) - read the label

Signal word: WARNING

Medical emergency: (800) 424-9300

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant,

Selected uses: black rot, powdery mildew

Comments: Tebuzol contains the same active ingredient, in the same concentration, as ΔElite and ΔOrius. Refer to the entry for ΔELITE for additional information such as RESISTANCE WARNING information.

TOPSIN M (thiophanate-methyl)

Signal word: CAUTION

Medical emergency: (866) 673-6671

Chemical family: benzimidazole

Resistance risk: high

Physical mode of action: protectant, some post-infection, some anti-sporulant

Selected uses: see below

Comments: Topsin-M is a benzimidazole fungicide very similar in activity to ^Benlate, which no longer is available. Please note that the standard (federal) product label for Topsin does not include pruning wound treatments to control pruning wound cankers, which is the only for which the product is recommended locally. However, Topsin M WSB (EPA Reg. No. 73545-16) has received a Special Local Need label in NY for control of grape pruning wound cankers (Eutypa dieback and Botryosphaeria). Special Local Need labeling for this is assigned SLN No. NY-070002; a copy of both the SLN and federal label must be in the possession of the user at the time of such an application.

VANGARD (cyprodinil) - read the label

Signal word: CAUTION

Medical emergency: (800) 888-8372

Chemical family: anilinopyrimidine

Resistance risk: high

Physical mode of action: protectant, post-infection, anti-sporulant

Selected use: Botrytis bunch rot

Comments: In research trials and grower usage, Vangard has consistently provided very good to excellent results against Botrytis bunch rot when applied at proper timings in conjunction with good canopy management practices. However, Vangard is at risk for resistance development by the Botrytis fungus; thus, the label restricts its use to a maximum of two applications per year. Because all of the other Botrytis fungicides—Endura, Elevate, Flint, Pristine, Rovral, and Scala—also are prone to resistance development, these materials should be rotated within and between seasons. Do NOT rely on one single material, or chemical family, year after year. Scala – another registered fungicide in the same anilinopyrimidine (AP) family as Vangard--is equally prone to resistance, and should the Botrytis fungus develop resistance to one of these chemicals, it will also be resistant to the other. Consequently, “rotating” Vangard and Scala with each other will NOT help delay resistance to either one. Therefore, make no more than a total of two applications per season of any AP fungicide. Refer to the Botrytis discussion under the “pest information” section for further information on fungicide management strategies for Botrytis.

VINTAGE (fenarimol) - read the label

Signal word: WARNING

Medical emergency: (888) 478-0789

Chemical family: sterol inhibitor [DMI subgroup]

Resistance risk: moderate

Physical mode of action: post-infection, antisporulant, limited protectant

Selected use: powdery mildew

Comments: Vintage contains the same active ingredient (fenarimol) as Rubigan, at the same concentration. The two materials are equally effective, and differ only in the “inert” ingredients used in their product formulation, i.e., Vintage has a less pronounced “chemical” smell. Refer to the entry for RUBIGAN for RESISTANCE WARNING information.

ZIRAM

Signal word: DANGER

Medical emergency: (303) 623-5716

Chemical family: dimethyldithiocarbamate

Resistance risk: low

Physical mode of action: protectant

Selected uses: black rot, Phomopsis

Comments: Do not enter the treated area within 48 hours after application unless proper protective clothing is worn. Ziram is similar to mancozeb products in its activity against black rot and Phomopsis, but is less effective than mancozeb against downy mildew. Ziram can be used from the 6-inch shoot growth stage until 21 days before harvest (maximum 24 lb/A/year). It is especially useful as a postbloom substitute for mancozeb where processor restrictions prohibit use of the latter.

Table 3.2.1. Physical modes of action of and resistance risk of fungicides used in management of grape diseases¹.
Fungicide			Protectant^a	Post-infection^b	Anti-sporulant^c	Eradicant^d	Resistance risk
azoxystrobin (Abound)^e			+	+/-^f	+	-	H
boscalid (Endura)			+?	+	+?	-	M/H
boscalid + pyraclostrobin (Pristine)			+	+/-^g	+	-	M-H
captan (Captan, Captec)			+	-	-	-	L
cyprodinil (Vangard)			+	+	+	-	M/H
dihydrogen potassium phosphate (Nutrol)^h			-	+	+	+/-	L
fenarimol (Rubigan, Vintage)^{e, h}			+/-	+	+	-	M
fenhexamid (Elevate)			+	+	+	-	M
ferbam			+	-	-	-	L
fixed copper (several formulations) and lime			+	-ⁱ	-	-	L
fluopicolide (^Presidio)			+?	+?	+?	-	H?
iprodione (Rovral)^e			+	+	+	-	M
kresoxim-methyl (Sovran)			+	+/-^f	+	-	H
mancozeb (Dithane, Manzate, Penncozeb)			+	-	-	-	L
mandipropamid (Revus)			+?	+	+?	-	M
mefanoxam (Ridomil)			+	+	+	-	H
myclobutanil (^Nova, Rally)^e			+/-	+	+	-	M
phosphorous acid (various formulations)			+/-	+	+	-	M
potassium bicarbonate (Kaligreen, Armicarb 100)^h			-	+	+	+/-	L
pyrimethanil (Scala)			+	+	+	-	H
quinoxyfen (Quintec)^h			+	-	-	-	M
spray oil (JMS Stylet, PureSpray)^h			+/-	+	+	+	L
sulfur (several formulations)^f			+	+	+	+/-	L
tebuconazole (ΔElite, ΔOrius, Tebuzol)^e			+/-	+	+	-	M
tetraconazole (^Mettle)			+/-	+	+	-	M
thiophanate-methyl (Topsin-M)^e			+	+	+	-	H
trifloxystrobin (Flint)^e			+	+/-^f	+	-	H
triflumizole (*Procure)^{e, f}			+/-	+	+	-	M
ziram			+	-	-	-	L
zoxamide + mancozeb (*^NYGavel)			+	+	+?	-	M
¹These ratings apply only to the diseases against which the products are labeled for control, and assume recommended rates and timings, and good spray coverage.
Key:
	+	significant activity
	+/-	limited activity, or only active against some target pathogens in this mode
	-	not active in this mode
	H = high, M = moderate, L = low
a. Active when present before the pathogen begins to infect.
b. Active when applied after infection has begun, but before symptoms appear.
c. Significantly reduces spore production when applied after infection has occurred, although symptoms may develop or persist.
d. Kills all or most of the fungal colony when applied after symptoms appear.
e. Activities diminished or absent against pathogens resistant to the material.
f. Significant post-infection activity against powdery mildew only.
g. Significant post-infection activity against powdery mildew and Botrytis only.
h. Significant activities against powdery mildew only.
i. Modest post-infection activity likely against powdery mildew.
* Federal restricted use pesticide; may be purchased and used only by certified applicators or used by someone under the direct supervision of a certified applicator.
*^NY Restricted-use pesticide in New York State.
^ Not registered for use in New York State at press time

Table 3.2.2. Effectiveness of fungicides for management of grape diseases¹.
Fungicide			Phomopsis cane and leaf spot		Black rot		Downy mildew	Powdery mildew		Botrytis bunch rot
azoxystrobin (Abound)			++		++++		++++^a	++++^a		+
boscalid (Endura)			0		0		0	++++		++/++++^b
boscalid + pyraclostrobin (Pristine)			+++		++++		++++^a	++++^a		++/++++^b
captan (Captan, Captec)			++++		+		+++	0		+
cyprodinil (Vangard)			0		0		0	+?		++++
dihydrogen potassium phosphate (Nutrol)			0		0		0	++		0
fenarimol (Rubigan, Vintage)^f			0		++		0	+++^f		0
fenhexamid (Elevate)			0		0		0	+		++++
fixed copper (several formulations) and lime^c			+		+		+++	++		0
fluopicolide (^Presidio)			-		-		++++	-		-
iprodione (Rovral)^g			0		0		0	0		+++^g
kresoxim-methyl (Sovran)			++		++++		++^a	++++^a		++
mancozeb (Dithane, Manzate, Penncozeb)			++++		+++		+++	+		0
mandipropamid (Revus)			-		-		++++	-		-
mefanoxam (Ridomil)^d			d		d		++++	d		0
myclobutanil (^Nova, Rally)^f			0		++++		0	+++^f		0
phosphorous acid (various formulations)			0		0		+++	0		0
potassium bicarbonate (Kaligreen, Armicarb 100)			0		0		0	++		0
pyrimethanil (Scala)			0		0		0	+?		++++
quinoxyfen (Quintec)			0		0		0	++++		0
spray oil (JMS Stylet, PureSpray)			0		0		0	+++		0
sulfur (several formulations)e			+		0		0	+++^e		0
tebuconazole (ΔElite, ΔOrius, Tebuzol)^f			0		++++		0	+++^f		0
tetraconazole (^Mettle)			?		++++		0	+++^f		0
thiophanate-methyl (Topsin-M)			++		+		0	h		h
trifloxystrobin (Flint)			++		++++		+^a	++++^a		++/++++^b
triflumizole (*Procure)^f			0		++?		0	+++^f		0
Ziram			++++		+++		++	0		0
zoxamide + mancozeb (*^NYGavel)			++ⁱ		++ⁱ		+++	+		0
¹These ratings are relative rankings, based on standard application rates, good spray coverage, and proper spray timing. Actual levels of disease control will be influenced by these factors in addition to varietal susceptibility and disease pressure.
Key:	++++ excellent	+++ good		++ moderate		+ slight			0 not effective
a. NOTE: Powdery mildew resistance to the strobilurin fungicides (Abound, Flint, Sovran) has occurred in multiple V. vinifera vineyards in the Finger Lakes and on Long Island, sometimes resulting in significant crop loss. When such resistance occurs, none of the strobilurin fungicides will provide commercial control of powdery mildew, and they must be tank-mixed with an unrelated effective fungicide to avoid crop loss. Pristine, a product that combines a strobilurin fungicide with an unrelated material (boscalid), has provided excellent control in stobilurin-resistant vineyards. Because this control comes only from the boscalid component, which also is at risk for resistance development, Pristine should be used sparingly and with caution where problems with strobilurins have been encountered. NOTE: Downy mildew resistance to the strobilurins is common in the mid-Atlantic and southern regions of the U.S., and is suspected in NY as well. The boscalid component of Pristine does NOT control downy mildew, so all of these materials must be tank-mixed with an effective DM fungicide if that disease has become resistant to the strobilurins.
b. Fair control at the lower rate labeled for powdery mildew, good to excellent control at the higher rate labeled for Botrytis.
c. Refers only to fixed copper formulations listed in Table 8.3. Most insecticides labeled for use on grapes are incompatible with lime. Check insecticide label for incompatibility with alkaline spray materials. See New York Food and Life Sciences Bulletin no. 118 for information on effects of alkaline hydrolysis on pesticides.
d. Ridomil MZ formulations (Ridomil + mancozeb) will give slight control of Phomopsis and black rot, due to the relatively low rate of mancozeb that is included. Ridomil copper formulations will provide moderate suppression of powdery mildew.
e. Sulfur activity is strongly influenced by rate and frequency of application, and by weather. It is highly effective when applied at relatively high rates and short (7-day) spray intervals, but efficacy can decline as intervals increase and/or rates decrease, especially in rainy weather.
f. Powdery mildew resistance to the DMI fungicides (, ΔElite, ^ Mettle, ^Nova, *Procure, Rubigan, Vintage) appears to be present at varying levels throughout most of the viticultural districts of New York and Pennsylvania. Although these materials continue to provide significant control in most vineyards, they generally are less active than in the past and should not be relied upon as the primary tool for powdery mildew management. Nevertheless, the DMI fungicides remain valuable in rotational programs with newer and often more active powdery mildew fungicides.
g. Although poorly documented, resistance to Rovral appears to be common in vineyards where this fungicide has been used regularly over a long period of time. Because Rovral resistance "dies down" over time if the product isn't used, it is recommended that this fungicide be avoided for 1 or 2 years where it has been used regularly in the past, then applied no more than once per season if and when use resumes. Rovral is very effective when not compromised by resistance.
h. Topsin-M is a benzimidazole fungicide very similar to Benlate. It is recommended only for protecting pruning wounds from canker diseases.
i. Rating based on low mancozeb dosage supplied by labeled rate of *^NYGavel.
* Federal restricted-use pesticide; may be purchased and used only by certified applicators or used by someone under the direct supervision of a certified applicator.
*^NY Restricted-use pesticide in New York State
^ Not registered for use in New York State at press time

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Pest Management Guidelines A Cornell Cooperative Extension Publication	New York and Pennsylvania Pest Management of Grapes
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