Commercial Grape Insect and Disease Control – 2022

Table 1.

 Table 2.

 Table 3.

Table 4.

 Table 5.

Table 6.

 Table 7.

  Table 8.

Table 9.

 Table 10.

Residue Reminder: Visible films of spray residue are unattractive on fresh fruit and difficult to remove

 

^r Restricted use Pesticide.

 

^* Chemical Group Classifications can be found at the following web sites:
Herbicides - http://www.plantprotection.org/hrac/, Insecticides- http://www.irac-online.org/, Fungicides- http://www.frac.info/.

^** Horticultural oils are physical toxicants which act as suffocant and entrapment insecticides.

 

^OMRI Organic Materials Review Institute (OMRI) listed for organic production.

READ ALL LABELS for important restrictions or warnings about tank mix compatibility or phytotoxicity warnings BEFORE APPLYING PESTICIDES. THE LABEL IS THE LAW.

 

Bee Precautions

Several insecticides listed are toxic to bees. Mow the vineyard floor before application if weeds or cover crops are blooming. Read individual labels for specific bee protection measures for each product.

 

Grape Root Borer

This pest is not common in Oklahoma. It is generally difficult to evaluate damage from grape root borer. Injury is most often associated with a slow decline of vineyards, when it can be associated at all.  If grape root borer is not a problem, there is no reason to risk destroying natural enemies (i.e., predators, parasites, pathogens). Therefore, treat with an insecticide only if necessary. Sampling is critical for several reasons: 1) The control program is relatively expensive; and 2) Use of an insecticide can create as well as solve problems. If you believe that this insect is affecting your vineyard’s performance, you may wish to begin the following program:

 

Immediately After Harvest

Sample - 10 vines per acre (but not less than 50 vines).
Examine - A circular site (3 feet in diameter) around the base of each plant, concentrating on the inner 1 foot, looking for shed pupal skins of the grape root borer moth.  If pupal skins are found beneath 5% of the vines examined, apply an insecticide next year.

 

35 Days Before Harvest

If previous year’s sample indicates a need to spray, apply Lorsban 4E, following label instructions.  Older vines are more likely to be infested.  Apply an insecticide as late as the label permits, but before harvest.

 

Green June Beetle, Japanese Beetle and Rose Chafer

As the crop reaches maturity, these beetle pests may become more of a problem, particularly feeding on ripened fruit.  When soil conditions are moist before or slightly after veraison, and organic matter in the surrounding area is high then these beetles can be quite common and difficult to control.  Careful attention to beetle infestation one month prior to harvest should be given to keep populations in check. Start treatment when first noticed. Use of Danitol up to 21 days before harvest can decrease populations.  Rotation to Sevin insecticide up to seven days before harvest will further aid in control.

 

Grasshoppers

Grasshopper control can and should be concentrated very early in the season before populations migrate into vineyard borders. Young, flightless nymphs may cause severe defoliation of border plants and progress into vineyards if left unchecked. If treatment is directed outside the vineyard, in pasture areas, then applications of Dimilin early in the season can prevent buildup of populations. When controlling grasshoppers inside the vineyard, then careful use of labeled compounds is the only recourse. Some level of effective control has been obtained using NOLO® Bait, a biological control agent containing tiny protozoan spores. This product is slow acting and does not store well, so use it early and often enough to be effective and to deplete your supply.

 

Botrytis Bunch Rot

Botrytis bunch rot is most commonly a problem on tight­-clustered French hybrid and Vitis vinifera cultivars. Fungicide application should be timed to occur right before the berries enlarge to tighten clusters. Proper timing and thorough spray coverage are essential for good control. Direct the spray toward the fruit, and use a minimum of 100 gal/A of water. Include a spreader-sticker with Rovral, especially at the 1.5 lb. rate. 

NOTE: Removal of leaves around clusters on mid- or low-wire cordon-trained vines before bunch closing has been shown to reduce losses caused by Botrytis.

 

Strobilurins

 

Abound Flowable

 Abound is in the same general class of chemistry as Sovran, Flint and Pristine (strobilurin) and is registered for control of black rot, downy mildew, powdery mildew and Phomopsis cane and leaf spot. (The active ingredient of Abound is azoxystrobin and there are several labeled products with the same ai. These include Aframe, Azoxystar, Azteroid, Acadia 2SC, Satori and Trevo). Abound is excellent for control of black rot and downy mildew and provides good control of powdery mildew. Abound is recommended at the rate of 10.0 to 15.5 fl. oz. per acre. In University tests, the rate of 11 to 12 fl. oz. provided good control of the above mentioned diseases.

NOTE:  Abound Flowable is very phytotoxic to apples of the variety McIntosh or varieties related to McIntosh. Do not use the same sprayer to apply Abound to grapes that will be used to apply other materials to apples.  Do not allow spray to drift from grapes to apples.

 

Sovran

Sovran is in the same general class of chemistry as Abound, Flint, and Pristine (strobilurin). It is registered for control of black rot, powdery mildew, Phomopsis cane and leaf spot, and downy mildew. The Sovran label gives different use rates for control of different diseases.  For black rot and Phomopsis cane and leaf spot the rate is 3.2 to 4.8 oz./A; for powdery mildew the rate is 3.2 to 4.8 oz./A and for downy mildew the rate is 4.0 to 6.4 oz./A. Sovran is excellent for control of black rot and powdery mildew, but is less effective than Abound for downy mildew control. Under heavy disease pressure, Sovran may not provide adequate control of downy mildew even at the higher rate. Unlike Abound, Sovran is not phytotoxic on certain apple varieties. Sovran has a 14 day PHI.  See label for further information and certain use restrictions.

 

Flint

Flint is in the same general class of chemistry as Abound, Sovran and Pristine (strobilurin). It is registered for control of black rot, powdery mildew and downy mildew. The Flint label provides different use rates for control of different diseases. For powdery mildew the rate is 1.5 to 2.0 oz./A; for black rot the rate is 2.0 oz./A and for downy mildew suppression, the rate is 4.0 oz./A.  Flint is excellent for control of black rot and powdery mildew, but is not highly effective against downy mildew, and is not recommended for control of downy mildew. Unlike Abound, Flint is not phytotoxic to certain apple varieties; however, Flint is very phytotoxic to Concord grapes. The label states “Do not apply Flint to Concord grapes or crop injury may occur.” See label for further information and certain use restrictions.

 

Pristine

Pristine contains a combination of two active ingredients (pyraclostrobin, 12.8% and boscalid, 25.2%). Pyraclostrobin is in the same general class of chemistry as Abound, Sovran and Flint (strobilurin). Boscalid has excellent activity against powdery mildew and good activity against Botrytis. With increasing resistance in powdery mildew to the sterol inhibiting fungicides and the strobilurin fungicides (Abound, Sovran and Flint). Pristine is an additional component in our resistance management programs for powdery mildew. Pristine is registered for control of anthracnose, black rot, downy mildew, powdery mildew and Phomopsis cane and leaf spot, with “suppression only” of Botrytis gray mold. A maximum of five applications may be made per season. Do not make more than two sequential applications of Pristine before alternating to a labeled fungicide with a different mode of action. The label also states “DO NOT use on Concord or Noiret due to foliar injury. Possible foliar injury could occur to Worden, Fredonia, Niagara, Steuben, Rougeon or related grape varieties.”

 

Resistance Management

 

For Strobilurin Fungicides

Strobilurin fungicides are highly susceptible to resistance development. Do not apply sequential sprays of Abound (or other labeled products with an ai. of azoxystrobin), Sovran, Flint or Pristine before alternating with a fungicide that has a different mode of action. Apply according to the label and no more than two times per year. Always read the label.

 

Important Note on Powdery Mildew:

In some locations, the powdery mildew fungus has developed resistance to the sterol-inhibiting fungicides such as Procure and the strobilurin fungicides (Abound, Sovran and Flint). All of these materials were highly effective for control of powdery mildew when they were first introduced, however in vineyards where these materials have been used for several years, reduced sensitivity or resistance may be present. For this reason, it is recommended that these materials not be used alone when powdery mildew needs to be controlled. To provide adequate control of powdery mildew, they should be mixed with sulfur, SuffOil-X, Quintec, Endura or potassium salts. Pristine is a combination of a strobilurin fungicide plus Endura; therefore, it can be used alone. Sulfur is an inexpensive and very effective fungicide for powdery mildew control. Unfortunately, some varieties are extremely sensitive to sulfur. On sulfur tolerant varieties, the use of sulfur should be considered.

 

Sulfur

There are many formulations of sulfur labeled for use on grapes with several options that are OMRI listed for use in organic growing.  Sulfur is available in dry flowable (DF) and flowable (F) formulations, as well as wettable powder (WP) and dusts (D). The dry flowable and flowable formulations greatly reduce the applicator’s exposure as compared to wettable powders and dusts. Use rates are different for different formulations as well as time of application. See the label for specific use rates. Some grape varieties, such as Concord and other Labrusca (American) types, are extremely sensitive to sulfur. Any product with calcium polysulfide or sulfur should never be applied to Chambourcin or Norton once it has broken bud. For other varieties, you can apply sulfur products to foliage at appropriate rate but temperatures need to remain below 85 F during or immediately following application or scorching may occur. Consult label for best time of day to apply. Sulfur loses efficacy for powdery mildew control at temperatures below 65 F. If using Captan, check label for sulfur interaction issues.

 

Additional Pesticide Information

 

Table 11. Insecticides

Table 12. Fungicides