Optimizing Nitrogen Fertilizer Management for High...
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Optimizing Nitrogen Fertilizer Management Strategies for High‐Yielding Spring Wheat in Manitoba Amy Mangin & Don Flaten, University of Manitoba John Heard, Manitoba Agriculture
Transcript of Optimizing Nitrogen Fertilizer Management for High...
Optimizing Nitrogen Fertilizer Management Strategies for High‐Yielding Spring Wheat in
ManitobaAmy Mangin & Don Flaten, University of Manitoba
John Heard, Manitoba Agriculture
Challenges to our traditional N fertilization management
• Current provincial guidelines do not address the high yield potential of current varieties that may exceed 90 bu/ac
• When high yields are achieved, risk of inadequate protein content for milling market is substantial
• The existing recommendation of 2‐3 lbs. N/bu spring wheat target yield creates large financial, agronomic and environmental risks
• Midseason fertilization may mitigate these risks but there is very little research for Manitoba growing conditions
Project Objectives1. Determine appropriate N rates, based on realistic yield and
protein goals for new high‐yielding varieties
2. Determine the most effective and efficient combination of N timing, rate, and source to meet yield and protein potential
3. Evaluate innovative soil tests for predicting mineralizable nitrogen during the growing season
4. Develop decision tools for midseason and post‐harvest evaluation of N sufficiency for yield and protein potential
Methods• Field trials conducted in SE MB over the 2016‐2017 field seasons (4 site‐years)
• Intensive agronomic management to maximize yields
• Factorial Design (Variety X N Treatment) arranged as a RCBD
VarietyN Rate (lbs N/ac) Source Timing/Placement
Spring In Season Spring In Season Spring In Season
Brandon (CWRS) and
Prosper (CNHR)
0
ConventionalUrea
Midrow band at seeding
5080110140170200
80 ESN:Urea (40:40)
140 ESN:Urea (100:40)
80 30
ConventionalUrea
Agrotain treated urea
Stem elongation, broadcast80 60
80 30 Flag leaf, broadcast80 60
80 30 UAN Post anthesis, foliar80 30 Urea Sol'n
Treatments
RATE
SOURCE
TIMING
0
20
40
60
80
100
120
0
50 lbs N/ac
80 lbs N/ac
110 lbs N/ac
140 lbs N/ac
170 lbs N/ac
200 lbs N/ac
AAC Brandon
Yield (bu/ac)
0
50 lbs N/ac
80 lbs N/ac
110 lbs N/ac
140 lbs N/ac
170 lbs N/ac
200 lbs N/ac
Prosper
Nitrogen Rate Response, 2016‐17, Yield
ANOVAVAR <0.0001N TRT <0.0001VAR*N TRT 0.0202
31.5 bu/ac 37.8 bu/ac
Residual NO3‐N: 40‐47 lbs/acYields adjusted to 13.5% moisture
50 lbs N/ac 100 bu/ac
140 lbs N/ac 112 bu/ac
0 lbs N/ac 67 bu/ac
200 lbs N/ac 129 bu/ac
Prosper
Brunkild, MBJuly 2017
60
65
70
75
80
85
90
95
100
Planting Stem Elongation Split Flag Leaf Split Post‐Anthesis Split
Yield (bu/ac)
110 lbs N/ac140 lbs N/ac
Nitrogen Application Timing, 2016‐17, Yield
Contrasts Probability value from Linear Contrast
Spring Application vs. Stem Elongation 0.0156*
Spring Application vs. Flag Leaf Split 0.1843
Stem Elongation Split vs. Flag Leaf Split 0.2610
Spring Application vs. Post‐Anthesis Split 0.0004*
Stem Elongation Split vs. Post‐Anthesis Split <0.0001*
Flag Leaf Split vs. Post‐Anthesis Split <0.0001*
AB AB
60
65
70
75
80
85
90
UAN Urea SolutionYield (bu/ac)
60
65
70
75
80
85
90
Urea ESN Blend
Yield (bu/ac)
Nitrogen Source, 2016‐17, Yield
Spring Source Post‐Anthesis Source
Contrasts Probability value from Linear Contrast
Spring Applied Conventional Urea vs. ESN Blend 0.1484
Post‐Anthesis UAN vs. Urea Solution 0.0320*
0 50 80 110 140 170 200
Carman17
0 50 80 110 140 170 200
Brunkild17
0 50 80 110 140 170 200
Carman16
8
9
10
11
12
13
14
15
16
17
18
0 50 80 110 140 170 200
Brunkild16
Protein(%)
Nitrogen Rate Response, 2016‐17, Protein
ANOVAVAR <0.0001N TRT <0.0001VAR*N TRT 0.6775
• Protein content consistently 1.65% greater in AC Brandon than Prosper
• N rate for maximum protein content = 140 ‐ 170 lbs N/ac• N rate for 13.5% protein content = 140 ‐ >200 lbs N/ac• N rate for optimum economic return = ???
Nitrogen Rate Response, 2016, Protein
8910111213141516
0 50 80 110 140 170 200
Protein (%
)
Lbs N/ac
Brunkild 2016
AAC BrandonProsper
8
9
10
11
12
13
14
15
16
0 50 80 110 140 170 200Protein (%
)
Lbs N/ac
Carman 2016
ANOVAVAR <0.0001N TRT <0.0001VAR*N TRT 0.6775
Residual NO3‐N: 40‐47 lbs/acYields adjusted to 13.5% moisture
Nitrogen Rate Response, 2017, Protein
8
9
10
11
12
13
14
15
16
0 50 80 110 140 170 200
Protein (%
)
Lbs N/ac
Brunkild 2017
AAC BrandonProsper
8910111213141516
0 50 80 110 140 170 200
Protein (%
)Lbs N/ac
Carman 2017
• Protein content 1.3 – 2 % greater in Brandon than Prosper• Minimum rate to match maximum protein = 140 ‐ 170 lbs N/ac• N rate for 13.5% protein content:
• Brandon: 50 ‐ 200+ lbs N/ac• Prosper: 200+ lbs N/ac
ANOVAVAR <0.0001N TRT <0.0001VAR*N TRT 0.6775
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
Planting Stem Elongation Split Flag Leaf Split Post‐Anthesis Split
Protein (%
)
110 lbs N/ac140 lbs N/ac
Nitrogen Application Timing, 2016‐17, Protein
Contrasts Probability value from Linear Contrast
Spring Application vs. Stem Elongation 0.0035*
Spring Application vs. Flag Leaf Split <0.0001*
Stem Elongation Split vs. Flag Leaf Split 0.0001*
Spring Application vs. Post‐Anthesis Split <0.0001*
Stem Elongation Split vs. Post‐Anthesis Split <0.0001*
Flag Leaf Split vs. Post‐Anthesis Split <0.0001*
B
C
A
Nitrogen Source, 2016‐17, Protein
Spring Source Post‐Anthesis Source
Contrasts Probability value from Linear Contrast
Spring Applied Conventional Urea vs. ESN Blend 0.2345
Post‐Anthesis UAN vs. Urea Solution <0.0001*
11.5
12
12.5
13
13.5
14
UAN Urea Solution
Protein (%
)11.5
12
12.5
13
13.5
14
Urea ESN Blend
Protein (%
)
Preliminary Conclusions• Based on means comparisons
140 Lbs. N/ac achieved maximum yield for Brandon, while 110 Lbs. N/ac achieved maximum yield for Prosper(1.7‐2.2 lbs. N/bu, Total N)
140‐170 Lbs. N/ac achieved maximum protein content across varieties
• Stem elongation and flag leaf split applications yielded at least as well as applications at planting
• Post‐anthesis applications reduced yields
• All split N applications increased grain protein content compared to when applied at planting Post Anthesis > Flag Leaf >Stem Elongation >Spring
• Foliar applied urea solution resulted in higher yield and grain protein content compared to UAN
• ESN blends produced yield and protein content similar to conventional urea
Acknowledgments• Manitoba Wheat and Barley Growers
Association• John Heard and colleagues in Manitoba
Agriculture• Crop Diversification Centres (WADO,
CMCDC, PESAI)• U of M Ian Morrison Research Station at
Carman• David Laudin • Antara Agronomy• Koch Fertilizer• Agrium• AGVISE Laboratories• Angie, Magda, Lanny, Megan, Trevor,
Thomas, Saad, Rockford, Meghan, Joel
Amy ManginDept. Soil ScienceUniversity of [email protected] (204) 384‐1196
