agricultural spray adjuvant technology -sorting out the adjuvant puzzle- activator adjuvants spray...
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Agricultural Spray Adjuvant Technology
-Sorting Out the Adjuvant Puzzle-
Activator Adjuvants
Spray Modifier Adjuvants
UtilityModifierAdjuvants
Utility Products
Steve Barnhart – Agriliance Regional Agronomist
?
Adjuvant Confusion!
• Compendium of Herbicide Adjuvants (Southern Illinois University – 1/02)– Lists 36 different companies selling various types
of adjuvants. There are more!– Lists 440 different adjuvants. There are many
more!
What is an Adjuvant?
• An adjuvant is any additive used in conjunction with a pesticide to increase biological activity and/or to modify various physical properties of a spray solution.
Importance of Adjuvants
• Pesticide Stability• Solubility• Compatibility• Foaming• Suspension• Surface Tension
• Droplet Size • Drift • Volatilization• Coverage • Adherence• Penetration
Adjuvants play a key role in controlling these variables
Spray applications are affected by many physical variables
Adjuvants Are Classified Into Four Categories
• Activator Adjuvants– Enhance Pesticide Performance
• Surfactants, Crop Oil Concentrates, Methylated Seed Oils, Fertilizer Solutions, Penetrants
• Spray Modifier Adjuvants– Affects Physical Properties Of Spray Solutions
• Stickers, Deposition Aids, Drift Retardants, Evaporation Aids
• Utility Modifier Adjuvants– Minimize Handling and Application Problems
• Compatibility Agents, Buffering Agents, Defoamers, Anti-foams
• Utility Products– Minimize Application Problems
• Foam Markers, Tank Cleaners
Adjuvants Types
• Surfactants (also called spreaders or wetting agents)– An adjuvant that reduces surface surface tension between
the spray solution droplets and the pest target’s surface, thus providing greater coverage.
• Crop Oil Concentrates– A combination of oil (petroleum or vegetable) and
surfactants/emulsifiers. Crop oil concentrates act as penetrants, stickers, spreaders (limited), humectants, etc.
• Methylated or Ethylated Seed Oils– An emulsified methylated or ethylated seed oil. Act as
penetrants, spreaders (limited), humectants, etc.
Adjuvants Types - cont.
• Penetrators– Enhance uptake of pesticides through target pests
surfaces.
• Spreader/Stickers/Extenders– Combine spreading and adhesive qualities to improve
coverage and retention of pesticide.
• Water Conditioning Agents– Reduce the antagonistic affects of impurities (Ca, Mg, Mn,
Fe, etc.) found in water carrier. Potentially greater pesticide efficacy results.
Adjuvants Types - cont.
• Humectants– Increase the drying time of spray solutions which provides
greater time for the pesticide to enter the targets surface. Used during high temperature, low humidity and low spray volume situations.
• Deposition Aid– Reduces the amount of fine spray particles that carry
pesticide out of target areas. (polyacrylimides, encapsulators, others)
– Reduces evaporation of the spray droplet; Used during high temperature, low humidity and low spray volume situations.
• Drift Control Agents– Reduces the amount of fine spray particles that carry
pesticide out of target areas. (polyacrylimides, encapsulators, others)
Adjuvants Types - cont.
• Compatibility Agents– Compounds that aid in stability and dispersion of various
pesticide formulations and spray carrier mixtures. • Buffer Agents/Acidifiers
– Generally lower the pH of the spray solution and reduce rapid changes in pH either higher or lower.
• Reduces the degradation of pesticides by chemical hydrolysis.– Dimate, Malathion, Sevin, etc.
– Some buffers are used to raise the solution pH for greater herbicide solubility (Example: micro-rate herbicide applications of Betamix + Upbeet + Stinger on sugar beets)
• Colorants– Used to alter the color of spray solutions.
Adjuvants Types - cont.
• Suspension Agents– Extend the period of time a pesticide will remain in
suspension and if agitation is stopped for a time, upon agitation they aid in re-suspension of the mixture
• Defoaming Agents– Suppresses foam of various pesticide solutions, aids in
filling tanks
• Foaming Agents– Used for marking swath width.
Who Regulates Adjuvants?
• Basically the industry is self-regulated
• Formulations are considered “trade secrets”– not disclosed to the public
Quality Issues
• Lack of consistent regulation
• Confusion and Opportunity
“Yes, there is a difference among adjuvants - All adjuvants are NOT created equal.”
(Dr. Richard K. Zollinger-NDSU)
Value of Spray Additives
FOLIAR ABSORPTION OF PURSUIT AND SURFACTANTS
0
20
40
60
80
100
Pursuit plus surfactantAdjuvant effects on Pursuit absorption
Ab
sorp
tio
n (
% o
f ap
plie
d)
Crop Oil Concentrate + Fertilizer
Nonionic Surfactant + Fertilizer
Crop Oil Concentrate
Nonionic Surfactant
Fertilizer
No Additive
• What value does the adjuvant bring?
Without adjuvants many herbicides would not perform!
Value of Spray Additives (Accent, Pursuit, Spirit, etc.)
Herbicide Investment
Surfactant Investment @15 GPA
Nitrogen Investment
Percent Absorption
$20.00 None Added None Added
3%
$20.00 $0.75/ac None Added
50%
$20.00 $0.75/ac $1.00 85%
Activator Adjuvants
Activator Adjuvants are SpecificWhy More Than One Activator Adjuvant?
• Herbicide Specific– Work well with some herbicides, but not all!
• Non-ionic surfactants work well with Roundup while oil based surfactants inhibit Roundup performance.
– Herbicides Differ
• Water soluble versus oil soluble
• Contact versus Systemic
Activator Adjuvants are SpecificWhy More Than One Activator Adjuvant?
• Weed Specific– Work well with some, but not all weeds!
• Oil based surfactants are generally more effective for annual grasses and lambsquarters which have waxy cuticles.
– Cuticle (wax type and thickness)– Leaf Surface (hairiness)– Leaf Angle (vertical or flat)
Activator Adjuvants are SpecificWhy More Than One Activator Adjuvant?
• Environmentally Specific– Soil moisture, temperature, humidity
• Non-ionic surfactants provide better crop tolerance during high humidity conditions than do oil based adjuvants. Meanwhile, methylated seed oil based adjuvants provide better control during very dry conditions compared to non-ionic surfactants or conventional crop oil concentrates.
Surfactants
Adjuvant vs. Surfactant
• The terms Adjuvant and Surfactant are often used interchangeably in our daily spray discussions.
• Surfactants are actually a specific type of adjuvant.
• All surfactants are adjuvants, but not all adjuvants are surfactants.
Surfactants
• Form a “bridge” between unlike chemicals that don’t readily mix– water and oil– water and the wax on a leaf surface
• Lower the surface tension of spray droplets
• Allow for more complete spray coverage and sticking on plant surfaces
• May contain fatty acids to further improve herbicide retention and penetration
Surfactants
Without Surfactant With Surfactant
Surfactants
• Complex long chain polar molecules
• Composed of alcohols and fatty acids
• Lipophilic “tail” and hydrophilic “head”
• Three general groups– Non-ionic, anionic, cationic
Surfactant Activity
Structure ActivityHydrophilic
Lipophilic
Water
Oil droplet
Charged Surfactants (Anionic, Cationic and Amphoteric)
• Anionic surfactants have a negative charge and have limited compatibility with pesticides.
• Cationic surfactants have a positive charge and have limited compatibility with pesticides.
• Amphoteric surfactants have both charges and may vary their charge with changes in pH.
• Charged adjuvants may be more effective with salts (glyphosate, 2,4-D amine, etc.)
Uncharged Surfactants (Non-Ionic)
• Uncharged or non-ionic surfactants are compatible with most pesticides
• There is a wide variety of non-ionic chemistry• Some inert chemicals are considered to be
adjuvants as they reduce surface tension. These chemicals (butanol, diethylene glycol, etc.) have little or no biological activity.
Surfactants
• Typical ingredients of surfactants– Surfactant active ingredient– Fatty acids– Alcohols– Water– Polyethylene glycols
Common Active Ingredients of Nonionic Surfactants
• Alcohol Ethoxylates - best biologically, very expensive
• Nonyl Phenol Ethoxylates - good biologically, in 95% of today’s surfactants, being looked at by EPA as a endocrine disrupter.
• Alkyl Octylphenol Ethoxylates - good biologically, expensive
• Alkyl Polysaccharides - good biologically, new chemistry, corn starch base, mixes well with AMS
• Urea Clathrates - good biologically, dry alcohol ethoxylate, expensive
• Fatty Acid Ethoxylates - good biologically, soybean base, may replace phenol ethoxylates
Common Active Ingredients of Nonionic Surfactants - cont.
• Tallow Amine Ethoxyalates - good biologically, used in Roundup Ultra, partially ties up free ions that can be antagonistic to the glyphosate molecule.
• Phosphate Esters - good biologically, also used in Roundup Ultra, partially ties up free ions that can be antagonistic to the glyphosate molecule.
• Fatty Acids - usually tree oils, biologically active
• EO/PO Block Copolymers (organosilicones) - expensive
• Siloxanes (organosilicones) - expensive
Other Ingredients Found In Surfactants
• Water• Alcohols (IPA-isopropyl alcohol)
– for storageability
• Polyethylene Glycol– used mainly as a filler, no biological activity
• Diethylene Glycol– used mainly as a filler, no biological activity
• Diols
Adjuvant Labels Can Be Confusing
• Nonyl phenol ethoxylate• Alkyl phenol ethoxylate• Poly ethoxylates• Alkyl aryl polyethoxylates• Alkyl polyoxyethylene• Polyethoxylated derivatives
These terms can all mean the same thing and may refer to the same constituent.
Physical Properties Used To Compare and Measure Surfactants
• Surfactant Load
• HLB - Hydrophilic:Lipophilic Balance
• Contact Angle
• Draves Wetting
• Surface Tension
Surfactant Load
• Is a measure of the exact content of true non-ionic surfactants in a particular product.
• Expressed as percentage.
• A product with a true surfactant load of < 50% may not meet the requirement for an adjuvant as specified by some pesticide manufacturers.
Comparison Of Active Ingredients In Typical Surfactants
- Performance Will Not Always Be The Same-
• 60% Alkyl Aryl Ethoxylate
• 20% Fatty Acids• 3% IPA• 7% Polyethylene
Glycol
• 10% Water
• 50% Alkyl Aryl Ethoxylate
• 20% Phosphate Ester• 10% Diol
• 5% IPA• 15% Water
90/10 Surfactant ?(80/10)
80/20 Surfactant ?(70/30)
Comparison Of Active Ingredients In Typical Surfactants
- Performance Will Not Always Be The Same
• 82% Nonyl phenol Ethoxylate
• 7.9% Fatty Acids• 0.1% IPA
• 10% Water
• 45% Nonyl phenol Ethoxylate
• 10% Fatty acid esters• 30% Glycols• 5% IPA
• 10% Water
90/10 Surfactant ?(89.9/10.1)
90/10 Surfactant ?(55/45)
HLB (Hydrophilic:Lipophilic Balance)
• HLB is the relationship between the nature of the hydrophilic and lipophilic portions of the surfactant molecule. The range of HLB is 1-20. The higher the value the more hydrophilic the surfactant. Most effective surfactants have a value between 10-18. The HLB is not measured, it is calculated. Research has shown that there is significant herbicide/HLB/weed interactions
HLB and Herbicide/Surfactant Solubility
101 20Oil Soluble(Lipophilic)
Water Soluble(Hydrophilic)
Prime OilDestinySuperb HC
PreferenceActivate PlusSilkin
Accent, Assure II,Atrazine,Beacon,Classic, Fusilade DX,Harmony GT, Poast, etc.
Sterling/Banvel, Blazer, Galaxy, Gramoxone,Liberty, Pursuit, Reflex, Cornerstone/Roundup/Touchdown, etc.
Herbicides
Surfactants
Contact Angle
• This is a profile measurement of a drop of water in contact with a solid surface. When a surfactant is added to water the surface tension of the solution is reduced and the spreads out over a greater area. This flatter droplet has a lower contact angle reading. A water droplet has a contact angle of 93 degrees. A superior wetter will have a contact angle of 45 degrees or less.
CONTACT ANGLE
• “Contact angle” (CA) is a profile measurement of a drop of water in contact with a solid surface. When a surfactant (wetting agent) is introduced into the solution, the surface tension is reduced and the water droplet becomes flatter.
• The lower the CA produced by the surfactant,the greater the spreading and coverage propertiesof that spray solution.
• Water has a CA of 93 degrees. A typicalsurfactant influences the contact angle30-45 degrees, and a “super wetter” surfactantcan reduce contact angles to 15 degrees or less.
Contact Angle - cont.
• Water 940
• Water + Preference (NIS) 380
• Water + Activate Plus (NIS) 350
• Water + Silkin (silicone NIS) 240
• Water + Prime Oil (COC) 580
• Water + Destiny (MSO) 590
Crop Oil Concentrates and Methylated Seed Oils havesurfactants in their formulation, but do not as effectivelyreduce contact angles like true surfactants.
Draves Wetting
• This is a test to measure the time in seconds it takes to completely wet a woven cotton skein. A superior wetter will require less than 20 seconds for wetting to occur. The lower the score in this test the better wetting characteristics the product has.
DRAVES WETTING TEST
Draves wetting correlates to how well a pesticide solution will wet and spread on a solid surface (i.e.: plant, weed, etc.). This standard method test measures the time (seconds) it take to wet a woven cotton thread.
A superior wetting agent at a 0.25% v/v concentration will require less than 20 seconds for wetting to occur. (Water measures at >300 seconds.)
The lower the score on this test the better wetting characteristics the product has.
Draves Wetting - cont.
• Water >300
• Water + Preference (NIS) 16
• Water + Activate Plus (NIS) 11
• Water + Silkin (silicone NIS) 2
• Water + Prime Oil (COC) >300
• Water + Destiny (MSO) >180
Crop Oil Concentrates and Methylated Seed Oils havesurfactants in their formulation, but do not have the wetting characteristics of true surfactants.
Seconds
Surface Tension
• Surface tension is a condition that exists at the free surface of a liquid. The surface tension test measures the force required to pull a floating ring off of the surface of a liquid. This force is measured in dynes/cm. Water has a value of 74 while typical spreaders will have a value of 30-50. Super wetters will be 10-30.
SURFACE TENSION
• “Surface tension” is a condition that exists at the free surface of a solution. The dynes per centimeter (dynes/cm) measurement in the test determines the amount of “force” required to pull a floating ring off the surface of the solution. The higher the dynes/cm, the more force is applied.
• Since surfactants affect tension, the lower thedynes/cm the better the coverage. Conversely,the higher the dynes/cm of the solution, thegreater the impact on coverage.
• The surface tension of water is approximately74 dynes/cm. Typical wetting agents will reducesurface tension to 30-50 dynes/cm, whilesuper wetters reduce this figure to 10-30dynes/cm.
Surface Tension - cont.
• Water 73
• Water + Preference (NIS) 35
• Water + Activate Plus (NIS) 32
• Water + Silkin (silicone NIS) 27
• Water + Prime Oil (COC) 36
• Water + Destiny (MSO) 52
Dynes/Cm
Water Conditioning Agents
Water Conditioning Agents
• Water Conditioning Agents– Reduce antagonism from hard water cations
(Ca++, Mg++, Fe++, K+, Na+, ZN++)• Free salts in water attach to sulfate ions
– In some cases can help overcome antagonism between certain herbicides
– Can lower pH and buffer spray solution• Reduces breakdown of certain pesticides due a
process called “Alkaline Hydrolysis”.
– Increase penetration of herbicide into plant cell membranes through “Ion-trapping”
Common Active Ingredients Terms in Water Conditioner Products
• Alkylpolyglucoside (corn syrup)• Alkylpolyglycoside• Alkylpolyoxyethylene glycol• Ammonium Salts • Ammonium Sulfate• Ammonium Nitrate• Ammonium alkyl aryl
sulfanates• Ammonium polyacrylates• Citrophosphate
• Glycerol acid• Hydroxy carboxylic acid• Phosphate esters• Phosphoric Acid• Plycarboxylic acid• Polyacrylic acid • Propionic acid• Sulphates• Urea• UAN
Nitrogen Fertilizer’s Role as a Water Conditioner
Nitrogen Fertilizers (NH4)
Accent Celebrity Plus Fusion Marksman Resource Accent Gold Clarity Galaxy NorthStar Roundup Assure Classic Glyfos Option Select Banvel/Sterling Cobra Harmony GT Permit Spirit Basagran Distinct Hornet Phoenix Steadfast Basis Exceed Laddok S-12 Poast Plus Stellar Basis Gold FirstRate Liberty Pursuit Sterling Beacon Flexstar Liberty ATZ Raptor Sterling Plus Blazer Fusilade Lightning Reflex Touchdown
• Weeds which respond to the addition of UAN solutions or AMS.– Foxtails, johnsongrass, quackgrass, woolly cupgrass,
velvetleaf, cocklebur, sunflower, P. smartweed, v. mallow, devilsclaw, lambsquarters and w. mustard.
• Herbicides which are enhanced by nitrogen
2,4-D AmineMCPA Amine
Nitrogen Fertilizers (NH4)
• Herbicides where antagonism from mineral salts in the water can affect their performance:– Roundup, Cornerstone, etc. (glyphostate)– Liberty, Liberty ATZ (glufosinate)– Banvel, Clarity, Distinct, Sterling (dicamba)– 2-4-D amine– MCPA amine
• Herbicides where UAN does NOT overcome the antagonism of mineral salts in the water; AMS must be used:– Roundup, Cornerstone, etc. (glyphostate)– Liberty, Liberty ATZ (glufosinate)
Nitrogen Fertilizers (NH4)
• Even in the absence of mineral salt impurities in the water, weed control of certain weeds is enhanced by the addition of UAN solutions or AMS.
Concerns with AMS/Polyglycolether Products
Product AMS recommended on Herbicide Label
AMS delivered by an ammoniated salt adjuvant containing 25% AMS at
2 qt/100 gallons Roundup 8.5 – 17 lbs./100 gallons 1.25 lbs./100 gallons Pursuit 2.5 lbs./AC 0.19 lbs./AC Accent 2-4 lbs./AC 0.19 lbs./AC
• Ammoniated Salt Adjuvants– Advertised as AMS substitutes
– Do not meet label recommendations for NIS or AMS
– Generally NOT approved
Value of Spray Additives
SPRAY GRADE AMMONIUM SULFATE.
AMMONIUM SULFATE SOLUTION
PREMIXES
505560
6570
7580
8590
95100
RRPW COLQ VELE
AMS AFFECT ON ROUNDUP ULTRA
University of Minnesota- Waseca
HARD WATER
WATER pH 8.2
DEIONIZEDWATER
WATER 800PPM CA
800 PPM CA +AMS
Roundup/Adjuvant/AMS Trial
30
40
50
60
70
80
90
100
Adj.1
Adj.2
Adj.3
Adj.4
Adj.5
Adj.6
Adj.7
Adj.8
Adj.9
Adj.10
Adj.11
NoAdj.
W/AMSWO/AMS
% Barnyardgrass Control (17 DAT)
Adjuvant
Roundup Original Rate = 16 oz/a; LSD (.10) = 2; Adjuvants rates varied by product
Roundup/Adjuvant/AMS Trial
30
40
50
60
70
80
90
100
Adj.1
Adj.2
Adj.3
Adj.4
Adj.5
Adj.6
Adj.7
Adj.8
Adj.9
Adj.10
Adj.11
NoAdj.
W AMSW/O AMS
% Waterhemp Control (17 DAT)
Adjuvant
Roundup Original Rate = 16 oz/a; LSD (.10) = 13.8; Adjuvants rates varied by product
Roundup/Adjuvant/AMS Trial
50
60
70
80
90
100
Adj.1
Adj.2
Adj.3
Adj.4
Adj.5
Adj.6
Adj.7
Adj.8
Adj.9
Adj.10
Adj.11
NoAdj.
W AMSW/O AMS
% Velvetleaf Control (17 DAT)
Adjuvant
Roundup Original Rate = 16 oz/a; LSD (.10) = 11; Adjuvants rates varied by product
Roundup/Adjuvant/AMS Trial
30
40
50
60
70
80
90
100
Adj.1
Adj.2
Adj.3
Adj.4
Adj.5
Adj.6
Adj.7
Adj.8
Adj.9
Adj.10
Adj.11
NoAdj.
W/AMSWO/AMS
% Foxtail Control (17 DAT)
Adjuvant
Roundup Original Rate = 16 oz/a; LSD (.10) = 2; Adjuvants rates varied by product
2003 Dumont Answer Plot
Crop Oil Concentrates
• Non-phytotoxic oils + emulsifiers (surfactants) – Generally 80-95% oil and 5-20% emulsifier– Petroleum based or vegetable in origin
• Surfactant portion aids in spreading/wetting• Increase spray retention/prolong drying time • Increase penetration through the leaf cuticle• More effective than NIS adjuvants in low
humidity, and on drought stressed or larger weeds
Accent/Beacon Adjuvant Trial Kansas State University
0102030405060708090
100
Accent+Prime Oil(1% v/v)
Accent Beacon + Prime Oil(1 v/v)
Beacon
% Shattercane Control (87 DAT)
Accent Rate = 0.168oz/a; Beacon Rate = 0.19 oz/a; LSD (.05) = 14
Methylated Seed Oil (MSO) -Typical Ingredients-
• Oils 85-92%– Seed Oil + methanol
• Emulsifier/Surfactants 8-15%– Akyl Aryl Ethoxylates– Castor Oil Ethoxylates– Polyethylene glycol esters– etc.
Beacon/Accent Adjuvant Trial
50
60
70
80
90
100
Activate Plus+ UAN
PrimeOil+UAN
Destiny+UAN Only UAN No Additives
% Velvetleaf Control (19 DAT)
Beacon/Accent Rate = 0.38 oz/a + 0.33 oz/a; Activate Plus = 0.25% v/v; Prime Oil and Destiny = 2 pt/a; UAN = 2 qt/a
LSD (.10) = 5
Minimizing Spray DriftMinimizing Spray Drift
Best Spray Management Practices To Minimize Spray Drift Issues
• Use good judgement– Consider wind speed and direction
– Consider climatic conditions
• Select the proper equipment– Manage spray droplet size
• Nozzle type, size & pressure
– Keep boom height low
• Use a drift control/deposition agent– Maximize spray deposition
– Reduce spray drift
It is necessary to consider all of the above in order to do the bestyou can to reduce drift and maximize herbicide performance.
Drift Control Agents
• “Encapsulators” – Suspends small capsules(150-180 Micron size) of
pesticide in the spray solution significantly reducing the amount of pesticide contained in drift susceptible fines.
– Placement & Placement Pro Pak• Do not affect spray droplet size
• “Thickeners or Viscosity Modifiers”– Increases the viscosity of spray solutions which in turn
increases droplet size and reduces the amount of drift susceptible fines.
– Corral Poly, Corral AMS Dry, Arrow four, AG1040• Do enlarge spray droplet size
• Neither a “Thickener” or an “Encapsulator”– InterLock
Can Drift Control / Deposition Aids Improve Pesticide Efficacy?
Yes !
Can Drift Control / Deposition Aids Improve Pesticide Efficacy? Yes !
European Corn Borer Damage as Influenced by Adjuvants
TreatmentRate % Visual Damage % Damaged Stalks
None ---- 73 67
Pounce 4 oz/a 37 33
Pounce +
Preference
4 oz/a
2 pt/100 g30 23
Pounce +
Placement
4 oz/a
4 oz/a27 23
Pounce +
Placement +
Preference
4 oz/a
4 oz/a
2 pt/100 g
23 17
Pounce +
Rivet
4 oz/a
2 qt/100 g30 23
LSD P=(0.05) 7.6 9.5
Source: Plant Research Service – Bethel, Missouri
Cotton Defoliation: 8/30/02
Dropp .2 + Finish 16 0z/Ac + Class Act Next Gen. 2.5 Gal/200 + 4 0z/Ac Placement
PLACEMENT!
NO PLACEMENT!
While the previous pictures show defoliation of cotton. Could this same canopy penetration enhancement carry- over to better control of such soybeaninsects as soybean aphids or spider miteswhich tend to colonize under leaves and down in the crop canopy? How about improved soybean rust control?
Probably!
InterLock 2004 Canopy Penetration Trial(Desert Air Ag – Mud Lake, Idaho)
Treatment Average: Droplets/cm2 % Improvement
Untreated 12.863%
InterLock + Preference (4 oz/a +1 pt/100 g) 20.8
Canopy Location Average: Droplets/cm2 % Improvement
Upper – Untreated 16.636%
Upper - InterLock + Preference (4 oz/a +1 pt/100 g) 22.5
Middle – Untreated 12.086%
Middle - InterLock + Preference (4 oz/a +1 pt/100 g) 22.3
Lower - Untreated 9.781%
Lower – InterLock + Preference (4 oz/a +1 pt/100 g) 17.6
Amistar (4 oz/a) fungicide
Airtractor 502 airplane, CP flat fan nozzles, 5 g/a at 120-140 mph.
Water sensitive paper used to evaluate and collect spray.
InterLock + Preference (4oz/a + 1 pt/100 g)
•Upper Canopy – 22.5 droplets/cm2
•Middle Canopy – 27.2 droplets/cm2
•Lower Canopy – 14.0 droplets/cm2Untreated
•Upper Canopy – 12.25 droplets/cm2
•Middle Canopy – 10.75 droplets/cm2
•Lower Canopy – 8.25 droplets/cm2InterLock 2004 Canopy Penetration Trial
InterLock for Soybean Rust
36.642.6
58.4
0
10
20
30
40
50
60
70
Headline Headline + InterLock Headline + InterLock+ Activate Plus
% C
on
tro
l
2004 I Brink ,South AfricaInterLock = deposition aid at 4 oz/aActivate Plus = non-ionic surfactant at 1 pt/100 g.
Interactions Which Affect Postemergence Performance
Adjuvants
Environment
Plants Herbicide
Selecting the Best Adjuvant or Adjuvant Combinations
Oils and FertilizersMethylated Seed Oils
Crop Oil ConcentratesSurfactants and Fertilizers
Nitrogen FertilizersSilicone Surfactants
Non-Ionic Surfactants
Spray Conditions
Good
Adverse
Weed Controland/orCrop Injury
High
Low
Thank You!
Steve Barnhart