Developing a Spray Program Stephen Jordan
UW-Madison
Considerations when developing a spray program
Varietal susceptibility to disease Vineyard disease history Fungicide options
Restricted Use Pesticides (RUPs)
Organic
Certified pesticide applicators or persons under their direct supervision http://ipcm.wisc.edu/Default.aspx?alias=ipcm.wisc.edu/pat Organic Materials Review Institute (OMRI)
Environmental impact Fungicide resistance management Cost vs product efficacy Re-entry Interval (REI) and Pre-harvest Interval (PHI)
Variety Susceptibility Variety Black Rot Downy Mildew Powdery Mildew Phomopsis Anthracnose Botrytis Sulfur sensitive Copper Sensitive Brianna ++ + + ? + ++ NO ? Edelwiess ? ++ ++ ? ? ? ? ? Frontenac ++ + ++ + + ++ NO ? Frontenac Gris ++ + ++ + + ++ NO ? LaCrescent ++ ++ ++ + + + ? ? LaCrosse +++ ++ ++ ++ + +++ ? ? Leon Millot + + ++ + + +++ YES ? Marechal Foch ++ + ++ + ++ + YES ? Marquette ++ + + ? ++ +++ ? ? St. Croix ? ++ ++ ? + ++ ? ? St. Pepin + +/++ +++ + + ++ NO NO Valiant ? +++ +++ ? +++ ? ? ? +=slightly susceptible or sensitive; ++=moderately susceptible or sensitive; +++=highly susceptible or sensitive; No=not
Most of these ratings were taken from research and observations from other states Unsure about a variety? talk to someone nearby who is growing it Resistant? Yes. Immune? Probably Not!
Protectant and Systemic Fungicides
Protectant fungicides act as a barrier to infection on the surface of the tissue
Must be applied prior to inoculum reaching the vine Does not protect new growth and must be re-applied Prone to environmental degradation
Rain, UV etc..
Systemic fungicides enter the plant tissue
Varying levels of penetration Varying levels of “curative” power (dose dependent) Can act as a protectant Limited protection of new growth after application Less prone to environmental degradation
Fungicide Resistance Management
Multi-target mode of action vs single target mode of action Fungicide Resistance Action Committee (FRAC) code on labels (not all!) Mix at-risk materials with materials that have different modes of action Alternate at-risk materials with materials that have different modes of action (different FRAC codes) Avoid using low rates with marginal control. Get complete coverage so that all parts of the plant receive an effective dose.
Anne DeMarsay, PhD
FRAC Code
FRAC Code
Mancozeb
Dithane, Dithane DF Rainshield , Manex II, Manzate, Penncozeb ethylene(bis) dithiocarbamate (EBCD fungicide) Broad spectrum protectant, no worries about resistance Workhorse of early-season disease control 66 day Post-harvet Interval (PHI) 24 hr Restricted Entry Period (REI)
Alternatives to mancozeb
Captan Can be used later in the season than mancozeb (0 day PHI) Protectant 3 day REI can make working in the vineyard a problem 24 lb/acre/year limit Can not be used with crop oils
Ziram Protectant 48h REI, 21 day PHI Great for black rot Overall less effective than mancozeb
Sterol inhibitor fungicides
The other work horse Also known as DMI fungicides Systemic, excellent post-infection activity (“kick-back”) requires fungicide resistance management Relatively affordable Highly effective against black rot and powdery mildew, effective against phomopsis Rally (Nova) (myclobutanil)
24h REI, 14 day PHI
Elite (tebuconazole)
12h REI, 14 day PHI
Strobilurins
Very effective, great protectant activity, poor “kick-back” activity
Slightly systemic
Tend to be more expensive
Must use fungicide resistance management (no more than 2 applications in a row, and do not rotate with another strobilurin)
Limited to 3 applications in a season (at max label rate)
Strobilurins
Abound (azoxystrobin)
Sovran (kresoxim methyl)
12 hr REI, 14 day PHI
Pristine (pyraclostrobin + boscalid)
4 hr REI, 14 day PHI.
12 hr REI, 14 day PHI, 5 day REI when cane tying, turning, girdling Potentially phytotoxic to labrusca
Flint (trifloxystrobin)
Less effective
Mefenoxam
Ridomil formulations with mancozeb, copper
Expensive
Very effective for downy mildew control
Very systemic, curative
With copper, effective against powdery mildew (but PHI of 42 days)
Sulfur
Sulfur is very effective for powdery mildew control
Can be mixed with most other fungicides except crop oils
Does not work well below 65°F and can be phytotoxic to vines at temperatures over 85°F
Some cultivars are sulfur sensitive (Foch)
Ask your winemaker
Coppers
Several different formulations (copper sulfate, copper hydroxide)
Cool temperatures can lead to phytotoxicity
Work well in controlling downy mildew infections, ok control of powdery mildew
Only use on copper-tolerant cultivars
Ask your winemaker
Phosphonates
Phosphorous acid fungicides
Agri-fos (potassium phosphate)
Aliette (fosetyl-Al)
Phostrol, Prophyt (Na, K, NH3 phosphites, phosphorous acids)
Work very well against downy mildew (good products for cleaning up foliage), some efficacy against other grape pathogens,
Broad spectrum fungicides (?)
Other fungicide options
Vangard, Elevate, Endura, and Rovral
Quintec
Effective for powdery mildew, anthracnose, not effective for black rot and downy mildew control
Quadris Top, (new product for grape)
Powdery mildew product, protectant
Topsin M
Most effective for Botrytis bunch rot control
Mix of an SI fungicide and a strobilurin
Revus Top (new product for grapes)
Mix of mandipropamid and difenoconazole (SI fungicide) University efficacy trials show excellent control of black rot, downy and powdery mildew
Other fungicide options
Crop Oils (JMS Stylet Oil, Saf-T-Side, etc)
Biologicals
Serenade, Sonata May play a role in organic production, not as effective as conventional fungicides
Potassium Salts
Effective for powdery mildew control and some insects Can remove the “bloom” from berries, not advisable for table grapes
Armicarb, Nutrol Some efficacy for powdery mildew only, short-lived protectants
Hydrogen Peroxide (Oxidate)
Surface anti-sporulant, not a protectant
Approximate fungicide costs/acre (2010) Broad Sprectrum Protectants ZIRAM 76 PENNCOZEB CAPTEC 4L CAPTAN 50W/MF
Cost ($)/Acre High Low Rate Rate 12.00 16.00 8.04 21.44 10.75 21.50 10.82 21.64
SI Fungicides ELITE 45 WP RALLY
14.37
15.19 23.95
Strobilurin Fungicides SOVRAN ABOUND FLINT
18.00 24.08 25.54
27.00 37.32 51.08
PRISTINE
25.95
40.54
Phosphonates PHOSTROL
Cost ($)/Acre Low High Rate Rate 11.01 22.01
Copper KOCIDE 3000 CHAMP
7.64 10.50
17.83 21.00
3.34 2.77 70.96
16.70 18.25 177.40
13.95 12.87 14.89 23.45
27.90 37.58 42.91 44.67 46.90
Sulfur KUMULUS SULFUR MICROFINE LIME SULFUR (Dormant) Others TOPSIN M RIDOMIL GOLD MZ OXIDATE SERENADE MAX VANGARD
Red = OMRI approved
Spray program options
No spraying
Prepare to be disappointed
Calendar Schedule
Fungicide application every x number of days
Phenological Schedule
Sprays are based on the growth stage of the vines
10-14 day intervals is the norm In areas with high disease pressure and susceptible varieties, this could be every 7 days
Can be problematic with vines at different stages
Ideally, we would use a combination of the calendar and phenological schedules with a large dose of flexibility Non-bearing vs bearing fruit
Dormant spray
Recommended for anthracnose, phomopsis and some insects
Might decrease powdery mildew inoculum
Lime sulfur
Won’t eliminate the disease from your vineyard
Caustic (hard on sprayer) Expensive when used as a dormant spray Does not store well (crystallizes, need hot water to mix) Stinks!
Is anthracnose and phomopsis a problem in your vineyard?
Yes, Apply lime sulfur No, Save your money
1” Shoots to pre-bloom
1” Shoots to pre-bloom
Goal is to protect the young, growing shoots
Black rot, powdery mildew, anthracnose, Phomopsis, downy mildew
14 day spray intervals should be adequate
Use a good protectant such as mancozeb or captan
Black rot problems or variety susceptibility, use mancozeb Downy mildew problems, use captan
If you miss a spray, or wet weather is delaying a spray, add an SI fungicide (Rally, Elite, etc…) to the tank mix for “kick-back” or post-infection activity
Pre-bloom to 5-6 weeks post-bloom
Immediate
prebloom through 5 to 6 weeks post-bloom is the most critical period for fungicide sprays
Pre-bloom to 5-6 weeks post-bloom
Pre-bloom to 5-6 weeks post-bloom
Primary goal is to protect the young, susceptible fruit
3 sprays should cover this period (14 day intervals)
we want the rest of the vine to be protected as well mancozeb or captan + SI fungicide (captan for the last spray?) strobilurin in the rotation
Rainy, warm weather and susceptible variety, shorten to 10 days (strobilurin more rain fast) Don’t rely only on a strobilurin fungicide during this period
3 applications total for the season, only 2 sprays in a row fungicide resistance management
5-6 weeks post-bloom to harvest (and beyond)
5-6 weeks post-bloom to harvest (and beyond)
Fruit should now be resistant to most pathogens Powdery and downy mildew on foliage
Bunch rots
How much disease can you tolerate Reduce over-wintering inoculum
Botrytis, sour rot, ripe rot
Switching from mancozeb (66 day PHI) to captan as primary protectant Typically, a drier late summer can help you reduce # of sprays Strobilurin fungicides are good for powdery mildew, downy mildew and bunch rots
Example program – vines bearing fruit
1” shoots, May 1st , mancozeb ($20) 6” shoots, May 15th mancozeb ($20) Prebloom/bloom, June 1st mancozeb + SI ($35) 1st Cover Spray, June 15th strobilurin ($40) 2nd Cover Spray, July 1st captan + SI ($35) 3rd Cover Spray, July 15th strobilurin ($40) 4th Cover Spray, (veraison) Spray August 1st, captan ($20) Clean-up Spray for downy mildew in September, Phosphorous Acid ($20) Total cost per acre in fungicides - $230
Fungicide program for non-bearing fruit
Not worried about fruit or harvest, so PHI goes out the window Grow tubes are an ideal environment for disease
Scout for foliar symptoms
Warm and humid Downy and powdery mildew are the greatest threat Anthracnose, black rot, and phomopsis may have come in on the nursery stock
Spray as needed
What I would keep in my fungicide storage shed
mancozeb and captan
A sterol-inhibitor fungicide
Effective for both powdery and downy mildew Good for late season control of bunch rots
Perhaps a Phosphorus acid fungicide (Phostrol, Prophyt, etc..)
Rally, Elevate, etc… Tank mix with one of the above protectants during the “CRITICAL PERIOD”
A strobilurin or strobilurin containing product
mancozeb for early season, captan for late season
Good for downy mildew on the leaves and affordable
A powdery mildew fungicide
What about insects?
Scouting is critical Scouting for phylloxera at the end of May Insecticides are applied as needed with scheduled fungicide sprays 2011 Midwest Small Fruit and Grape Spray Guide is a great reference
Phylloxera insecticide trial - 2010 Number of galls per leaf
42.6
$27
All foliar applications 2x after bloom
36.7 29.7
$17
16.2
$28
9.3
6.5
$55
3.9
Making tank mixes
Fill the tank ¼ - ½ full and begin agitation When mixing chemicals, add in the following order: 1. 2. 3.
4. 5. 6.
Wettable Powders Dispersible Granules Flowables Emulsifiable Concentrates Solutions Crop oils or surfactants
The mixture should be agitated after each addition.
Reminders for proper tank mixing
Familiarize yourself with the adjustments specific to your sprayer, not all sprayers operate the same and are adjusted differently Be sure the sprayer is parked on a level surface Know the exact tank volume Mark the tank volumes where they can easily be read Calibrate the sprayer Choose a formulation that best meets the need of a particular application Read the label and be aware of mixing precautions and personal protection equipment Mix only what is needed for that day
Fill half the tank with clean water, never add concentrated chemicals to an empty tank Start the agitation before adding any chemicals
Reminders for proper tank mixing
To avoid back-siphoning of chemicals, there should be no direct connection between the water source and the sprayer tank Properly measure and add the chemicals to the tank If using different formulations, follow the mixing order above Sometimes it is easier to premix the chemicals into a slurry before adding to the tank Rinse any mixing containers and pour the rinsate into the tank Fill the tank to its final volume, avoid over-filling the tank Properly dispose of all empty pesticide containers Properly clean-up and dispose of any spilled chemical or pesticide solution Apply the pesticide according to labeled directions
Stephen Jordan 608-228-6932
[email protected]
