ENGAGE AGRO
an introduction to
PLANT
GROWTH
REGULATORS
TABLE OF CONTENTS
What are Plant Growth Regulators
1
PGR’s in Cereal Production
2
How PGR’s Work in Cereal Crops
3
Wheat Growth Stages & Application Timing
4
Identifying Growth Stage 30 - 32
5
Canadian Field Results 2011 - 2014
6
Updated Canadian Field Results 2015
7
Wheat Varieties & PGRs
8
Technical info
9
References
9
ENGAGE AGRO
WHAT ARE PLANT GROWTH REGULATORS? (PGRs)
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PGRs are a class of chemicals used in a variety of crops worldwide to modify the growth of plants.
PGRs reduce plant height and increase stem thickness in cereal crops.
PGRs benefit crop production by modifying the balance of plant hormones.
PGRs help reduce lodging and maintain yield potential in cereal crops.
PGRs that reduce plant height and lodging are registered through the PMRA
There are two primary types of PGRs with differing modes of action used in cereal crop production.
UNDERSTANDING PLANT HORMONES
Plant hormones:
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are signaling molecules that regulate plant growth and development
are not nutrients, but naturally occurring chemicals that promote and influence
the growth, development, and differentiation of cells and tissues in plants
are generally categorized into five “classical” groups
1
Auxin & Cytokinin hormones
work together to regulate plant
growth relative to root
development.
HORMONE
Auxin
Cytokinins
Ethylene & Gibberellins are
the hormones targeted by
the two different types of
plant growth regulators in
cereal crops.
ACTION
Stimulate
Plant
Growth
BEHAVIOURAL CHARACTERISTICS
Stimulates cell elongation and facilitates the tropic response of
bending due to gravity and light. (Causes plants to grow towards the
light source)
Stimulates cell division and the growth of lateral buds. This is what
causes lawns to become thicker when grass is cut frequently.
Gibberellins
(GA)
Stimulates cell elongation and cell division to give plants their height.
Abscisic Acid
(ABA)
Stimulates the closure of stomata (tiny pores on the leaf of the plant
that allow the plant to breath) and usually inhibits growth. ABA
prepares the plant for stress or dormancy
Ethylene
Ethylene stimulates the
release of dormancy and
induces fruit ripening.
Bananas shipped to northern
countries are often picked
green and treated with an
ethylene producing
compound to induce ripening
when required.
Inhibit
Plant
Growth
Stimulates fruit ripening. Misapplied ethylene can cause stunted
growth and twisting of plants, and abnormal stem thickening.
PGRs in Cereal Production
PGRs are used on cereals to prevent lodging by helping plants
develop shorter, thicker, stronger stems.
Lodging in cereal crops occurs as a result of cultivar
susceptibility, weather, and crop management. Increasing fertility
and seeding rates will often increase lodging.
Crop lodging
 interferes with water and nutrient uptake
 reduces light interception
 increases disease potential
 reduces quality
 increases harvesting cost
 reduces grain yield
Gibberellin stimulates stem
growth through cell division
and elongation. Gibberellin
production is highest during
periods of rapid growth.
Lodging is a major limiting factor in attaining high yields from
increased nitrogen fertilization.
PGR’s are sprayed on the crop in the same way as an herbicide
or fungicide.
PGR TREATED
UNTREATED
2
HOW PGRS WORK IN CEREAL CROPS
Cereal plant growth regulators fall into two main groups:
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Ethylene releasing compounds
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add the hormone ethylene onto the plant
reduce height and thicken stems when applied within a narrow application window
may harm the plant when applied outside of their narrow application window
Anti-Gibberellin Products
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reduce gibberellin production which reduces plant height and thickens stems
significantly reduces the risk of lodging and yield loss in cereal grains
are already in use globally in a wide variety of crops.
There are several anti-gibberellin active ingredients used as PGRs primarily in cereals crops
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Trinexapac-ethyl & Prohexadione Ca
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Trinexapac-ethyl & Prohexadione Ca reduce gibberellic acid (GA) production late in the
biosynthesis of GA, and has a short residual activity. Trinexapac ethyl is often tank mixed
with Chlormequat because they are complimentary.
Chlormequat
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Chlormequat reduces gibberellic acid (GA) production early in the biosynthesis of GA,
and has a long residual activity. Since its introduction for use in 1965, Chlormequat
Chloride has become the standard for lodging control in cereals.
Comparison of the major plant growth regulators used in Europe
PGR
COMPARISON
ETHEPHON
Mode of Action
Releases Ethylene
Can cause stunted growth, abnormal
stem thickening
TRINEXAPAC ETHYL &
PROHEXADIONE Ca
UNFORMULATED
CHLORMEQUAT
Inhibits LATE stages of
gibberellin biosynthesis
Inhibits EARLY stages of
gibberellin biosynthesis
MANIPULATOR®
by ENGAGE AGRO
Inhibits EARLY stages
of gibberellin
biosynthesis
Minimum Temp.
15°C
10°C
8°C
1°C
Application
window
GS 37 – 45
Early flag – swollen boot
GS 31 – 32
5 – 6 leaf
GS 23 – 31
2 – 6 leaf
GS 12 – 39
2 leaf - flag
PGRs FOR CANADA
PGRs with older formulations had two significant limitations that prevented their use in Canada
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a narrow application window
a requirement for warmer temperatures (at least 8°C) in order to work
MANIPULATOR Plant Growth Regulator
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utilizes Chlormequat, an established, widely accepted active ingredient in a new formulation that
makes it ideal for use in Canadian growing conditions
is a new formulation that includes safeners and low temperature activators
provides improved performance and application flexibility
3
PGR APPLICATION TIMING ON WHEAT
The chart below shows the results of a replicated research plot done by the Northeast Agriculture Research
Foundation in Melfort, Saskatchewan. The plots were seeded with identical fertility packages.
When MANIPULATOR is applied at herbicide timing (GS 21) it will result in a dramatic reduction in plant height and a
reduction of lodging. In fields where lodging is not an issue, wheat treated with MANIPULATOR may not experience a
yield increase.
When MANIPULATOR is applied at flag leaf stage (GS 39) a significant reduction in height and a yield increase can
be expected compared to untreated wheat.
The best time to apply MANIPULATOR plant growth regulator is at the 5 to 6 leaf stage. (GS 30 - 32). If applied at
GS 30 - 32, producers can expect a reduction in plant height and lodging, and a yield increase.
105
100
Height (cm)
95
Yield (bu/ac)
90
85
80
75
70
65
Untreated
Untreated
GS-21
GS-30 - 32
GS21 Herbicide timing GS31 5-6 leaf stage
Herbicide Timing
5-6 Leaf Stage
GS-39
GS39 Flag Leaf stage
Flag Leaf Stage
IDENTIFYING GROWTH STAGE 30 - 32
Pull a sample which represents the average growth stage of the field.
The wheat in this picture is at GS 30.
Identify the main stem.
This stem is usually the largest with the thickest stem. This plant is in GS 30.
Remove the tillers.
Cut the roots off at the base of the plant,
then make a lateral cut from the base of the stem.
Identify the head. If the head is more than 1 cm above the ground, and the first
node is not visible, the plant is in GS 30.
GS 30
If the head is 1 cm above the first visible node, the plant is in GS 31
If the head is 1 cm above the second node, the plant is in GS 32.
GS 32
5
CANADIAN FIELD RESULTS 2011 - 2014
Below is a summary of all Canadian plot results conducted from 2011 to 2014. In hard red spring varieties
the trends show a height reduction of 10% or greater 83% of the time and a yield increase of 7.5% or
greater 63% of the time.
120%
Hard Red S.W.
Occurrence
100%
CPS
80%
HEIGHT REDUCTION
60%
40%
20%
0%
5% +
90%
10% +
15%+
20%+
Hard Red S.W.
80%
70%
CPS
YIELD INCREASE
Occurrence
60%
50%
40%
30%
20%
10%
0%
5% +
7.5%+
10%+
MANIPULATOR
CPS
Height Reduction
12 Trials
Occurrence
5% +
100%
10% +
67%
15%+
33%
20%+
8%
Hard Red S.W.
35 Trials
Height Reduction
Occurrence
5% +
95%
10% +
83%
15%+
53%
20%+
20%
CPS
12 Trials
Yield Increase
Occurrence
5% +
33%
7.5%+
25%
10%+
8%
Hard Red S.W.
35 Trials
Yield Increase
Occurrence
5% +
85%
7.5%+
63%
10%+
55%
UNTREATED
6
UPDATED CANADIAN FIELD RESULTS 2015
Long term study - plot results 2013-2015. Manipulator applied at GS 31
(Indian Head Agricultural Research Foundation)
Links to 3rd party 2015 research on MANIPULATOR PGR
East Central Research Foundation (Yorkton)
• Impact of Manipulator on wheat with differing lodging resistance at high rates of N fertility
• Impact of Manipulator timing and N fertility on wheat lodging and yield
www.ecrf.ca
Indian Head Agricultural Research Foundation (Indian Head)
• Optimal Nitrogen rates for wheat with and without Plant Growth Regulators.
http://iharf.ca
Irrigation Crop Diversification Corporation (Outlook)
• Demonstration of Plant Growth Regulator Application on irrigated wheat production
http://irrigationsaskatchewan.com/icdc
Northeast Agriculture Research Foundation (Melfort)
• Optimal Nitrogen Rate with Plant Growth Regulators and Fungicides for Spring Wheat
http://neag.ca/
Wheatland Conservation Area Inc. (Swift Current)
• Plant Growth Regulators and N Rates in Durum Wheat
http://wheatlandconservation.ca/home.html
7
WHEAT VARIETIES & PGRS
PERFORMANCE
FEATURES &
FORMULATION
Different varieties react differently to applied plant growth regulators. Three years of test data demonstrate a
reduction in height and lodging in CPS varieties, however, in the absence of lodging in the untreated section we
do not see a yield benefit. In hard red spring and durum varieties a yield increase was realized even in the
absence of lodging in the untreated section.
Formulation:
• Chlormequat chloride (620 grams / Litre + Proprietary Low Temp. Activators + Safeners)
• Suspension Concentrate (SC)
• Systemic
Features:
• Performance not affected by temperature as low as 1°C
• Safening System
• Wide application window from growth stage 12 – 39 (2-3 leaf to flag)
• Excellent tank mix compatibility
Even in varieties that didn’t show a reduction in
growth height when treated with Manipulator, plant
standability was enhanced by stronger, thicker stems.
8
SHORTER
STRONGER
BETTER
REFERENCES
MANIPULATOR PLANT GROWTH REGULATOR
Kende, H, and Zeevaart, J. The Five ‘Classical’ Plant Hormones. The Plant Cell 9.7
(1997): 1197–1210. Print.
For use on: Wheat (spring & winter)
Alberta Agriculture and Rural Development 2008 Lodging of Cereal Crops. (2008,
September 10). Retrieved from http://www.agriculture.alberta.ca
Active Ingredient: Chlormequat chloride
Kurepin, L., Ozga, J., Zaman, M., Pharis, R. 2013. The physiology of plant hormones in
cereal, oilseed and pulse crops. Prairie Soils and Crops Journal. 6:7-23 Retrieved from
www.prairiesoilsandcrops.ca
Formulation: Suspension concentrate
Navabi, A., Iqbal, M., Strenzke, K., and Spaner, D. 2006. The relationship between
lodging and plant height in a diverse wheat population. Can J Plant Sci. 86:723-726
Packaging: 2 x 10 litre jugs
Rademacher, W. and Brahm, L. 2010. Plant Growth Regulators. Ullmann's Encyclopedia
of Industrial Chemistry.
Mode of Action: Inhibits gibberellin production
Rademacher, W. 2009. Control of lodging in intense European cereal production.
Presented at Plant Growth Regulation Society of America Conference 2010 pg 61-69.
Retrieved from www.pgrsa.org
Application rate 1.8 Litres / Hectare or 0.7 Litres / Acre
1 x 10Litre jug treats 14 acres
Water volume : 10 gal. / Acre
Rademacher, W. 2000. Growth Retardants: Effects on gibberellin biosynthesis and
other metabolic pathways. Annu. Rev. Plant Physil. Plant Mol. Biol. 51:501-531
Application timing: Full window (2 leaf to flag leaf)
Optimal Timing: 5-6 leaf stage
Rain fast – 2 hours
Taiz, L., and Zeiger, E., 2010. Plant physiology.5th ed., International ed. Sunderland,
Mass.: Sinauer Associates.
Silverstone, A. L., and T. P. Sun. 2000. Gibberellins and the green revolution. Trends
Plant Sci. 5:1-2
UNTREATED
MANIPULATOR
9
ENGAGE AGRO
tel. 866.613.3336
[email protected]
www.engageagro.com