to mix or not to mix: that is the question? (tank-mixing herbicides and fungicides) eric p. prostko...
Post on 19-Dec-2015
220 Views
Preview:
TRANSCRIPT
To Mix or Not to Mix: That is the Question?
(Tank-mixing Herbicides and Fungicides)
Eric P. Prostko
Extension Weed Specialist
Department of Crop & Soil Sciences
University of Georgia
Why tank-mix agrochemicals?
• Advantages– Increase spectrum of control– decrease time and labor cost– less vine damage– decrease soil compaction
• Disadvantages– Reduced control– Increased crop injury– Physical incompatibility– different spray volumes/nozzle types– adjuvant recommendations
Spray Volumes and Nozzle Tips
• What is the best water volume to use for ……..– fungicides– herbicides
• What is the best nozzle to use for….– fungicides– herbicides
Nozzle Tips
Nozzle Tip
Herbicides Fungicides
Contact Systemic Contact Systemic
AI G E G E
Turbo Teejet
VG VG VG VG
XR
Flat Fan
E G E G
Turbo
Floodjet
NR VG NR VG
Whirl rain cone
VG VG E E
Hollow cone
NR G VG VG
What happens when you mix chemicals?
• additive
* 1 + 1 = 2
• synergistic
* 1 + 1 = 3
• antagonistic
* 1 + 1 = 1 or less
Antagonism
Gramoxone Max 8 ozs/A
Gramoxone Max10 ozs/A
+ Storm (1.5 pt/A)1 DAT
What do the labels tell us?
• In most cases, not very much
• Unclear, vague, and confusing
• Trial and error• Has someone else
done it?
Cadre Tank-Mixes
Headline
MONCUT 70DFECHO® 720 AG
PropiMax* EC
Nichino America ARTISAN
What have we learned?
• Generally no major problems but…..
• Impossible to test under all environmental scenarios
• There are some specific problems
Annual Grasses and Select(Jordan et al. 2003. Peanut Science 30:1-7)
• More of a problem when applied in 25 GPA than if applied in 10 GPA
• % of comparisons where control was reduced– Kocide, ManKocide, Tenn-Cop = 80%
• 7-75% reductions in control– Bravo and others = 69%
• 2-60% reductions in control– Abound = 60%
• 5-13% reductions in control– Folicur and Tilt did not reduce efficacy
Texas panicum control with Cadre/fungicide tank-mixes, 2002 (67 DAT) .
83 82 78 77 7367
75
0
20
40
60
80
100
None BravoWS
Tilt +BravoWS
Headline Abound Folicur Moncut
Fungicide
Con
trol
(%
)
LSD 0.05 = 20LSD 0.10 = 17
A New Publication(For more specifics) • Tank Mixing Chemicals
Applied to Peanut Crops: Are the chemicals compatible?
• June 2004
• Regional publication housed at NCSU (AGW-653)
• Available on-line at: http://www.peanut.ncsu.edu/ag653.pdf
New POST Labels for 2005
• Strongarm– 24c label in GA– No fungicide
tank-mix information
• Cobra
– Label says do not tank-mix
Before spraying…..
• Read label• Water volume
compatible for both• Nozzle type• Contact county agent• Check for physical
compatibility– Jar test
Mixing Order
• some water (1/2) + agitation• water soluble packets• wettable powder in slurry• DF or WDG• liquid flowables• EC• NIS/COC/AMS/UAN• Remaining water
(AMS then glyphosate)
Two-Jar Test
• 1 pt of carrier (water) to each of 2 qt jars• ¼ teaspoon of compatibility agent to 1 jar
– Blendex (Helena)– Mix (Drexel)– Unite (Loveland)
• To each jar, add required amount of pesticide in order suggested previously. Shake well after each addition.
• After all have been added, shake for 15 seconds and let stand for 30 minutes
Other issues
• Adjuvants– How is fungicide
formulated?– How bad are the
weeds?• What about …..
– insecticides– fertilizer– 3 or 4 way mixes
www.gaweed.com
top related