Late-vegetative Nitrogen Applications

for High-Yield Corn

Tony J. Vyn, S. M. Mueller, K. Chen, R.A. Omonode,

L. Olmedo Pico, T.D. West, Farmers and Other StudentsPurdue University

Presentation to South Dakota CCA Conference

in Sioux Falls, SD, on December 14, 2017

Research Context:On-going Experiments with Strip-Till and No-till Corn

and Associated Management Options:

1. Nutrient Placement, Rate, Timing, and Source

2. Corn Management (hybrid, plant density, rotation)

3. Greenhouse gas emissions from different 4R N management

Over-application of N an

environmental issue

USDA-NRCS

Higher and Later N Uptake in Modern Corn Hybrids

Source: S. M. Mueller and T.J. Vyn 2016 (Frontiers in Plant Science)

Mean N rates in lbs N acre-1:

151 153

Timing and Source of N

Uptake by Plants and Grain

N

N

N

Ciampitti et al., 2013 Agronomy Journal

Photo: ACRE, 2014

Study of Dekalb Hybrids from 1967 to 2005 and Their

Response Changes to Nitrogen and Plant Density Management

(2012-2014)

West Lafayette, IN, N rate effect on Dekalb hybrid yield

gains with year of commercial release (2013-2014)

Slope: 50N: 1.1 ns, R² = 0.88***

200N: 1.6 ns, R2 = 0.95***

0

50

100

150

200

250

1960 1980 2000 2020

Gra

in Y

ield

(bu/a

c)

Era

50N

200N

Source: Keru Chen et al., Field Crops Research, 2016

Hybrid

(commercial release

year)

Grain Yield

(bushels/acre)

Total Plant N

Uptake

(pounds/ac)

Post-silk Plant N

Uptake

(% of final total

uptake)

DKC61-69VT3 (2005) 226 240 37

DKC61-72RR (2005) 225 244 38

DKC XL72AA (1975) 189 203 30

Effects of two “modern” hybrids (2005) versus a common older hybrid (1975)

on corn grain yield, total N uptake, and post-flowering stage N uptake

when N rate = 200 pounds N/acre (mean of 3 plant populations from 22,000 to 42,000/acre and 3 site-years in NW + NC Indiana in 2012-2013).

Data Source: K. Chen (Ph.D. Student) & T.J. Vyn

What About Late-Season N?

Photo by Mike Shuter, 2014

Late-Split N Applications with Older versus “Modern” Pioneer Hybrids (2014-2016)

Methodology

Main Treatment:

N rates

Treat.

Name

Lbs N

V3-V4

Lbs N

V12-V14

0 0

140 140

180 180

220 220

180S 140 40

220S 180 40

Sub-Treatment:

Hybrid (Release

year)

1. Pioneer 3394 (1991)

2. Pioneer 3335 (1995)

3. Pioneer 1498 HR (2012)

4. Pioneer 1360 HR (2014)

“Late-split N” Yield Response

with Pioneer 1360 in 2015

0

50

100

150

200

250

300

0 N 140 N 180 N 220 N 180L N 220L N

Yield

(bu/acre)

Source: Mueller et al., Agron. J., 2017

Maize N Recovery Responses to Late-

Split N in 2014-2016

S.M. Mueller et al., Agronomy Journal, 2017

Average of 4 hybrids

0

10

20

30

40

50

60

70

80

2014 2015 2016

140 180 140 + 40

a

aa

bN Fertilizer

Recovery (%)

a

b

Nitrogen Timing in Continuous Corn on Irrigated

Sandy Soil (LaCrosse, IN) with DKC66-42 in 2016

0

20

40

60

80

100

120

140

160

180

200

220

240

15 N 115 N 165 N 215 N 265100% at Plant 50% at Plant + V6 Last 50 lbs @ V12

Grain

Yield

(bu/acre)

f f f

e e

dcd

abcdabc

bcd

abcabcabcd

aba

158

186189

200

213

Source: Lia Olmedo Pico and T. Vyn, 2016

Hybrid Recovery of Late-

Season N Applications?

Pioneer Hybrid Yield Resiliency in Response

to UAN applied at the R1 stage versus the

V5 stage (West Lafayette, 2016)

0

20

40

60

80

100

120

140

160

180

200

220

240

260

1976 1995 2003 2016

0 N V5 @ 200 N R1 @ 200 N

Source: Mueller and Vyn, unpublished, 2016

Grain

Yield

(bu/acre)

Hybrid Introduction Year

Nitrogen Recovery Efficiency with Pioneer Era

Hybrids (Two N timing treatments; 2016 only)

0.000

10.000

20.000

30.000

40.000

50.000

60.000

70.000

80.000

1946 1958 1967 1976 1995 2003 2015

Era NRE

200_0 150_50

Source: Mueller and Vyn, unpublished, 2017

On-farm Studies with Intentional

Late-Season N applications of 30 to 50 pounds

N

Equipment Option Focus:

Side-dress Nitrogen Timing and Placement

1. At-plant (zero vs. 77 and 177 pounds per acre; all broadcast)

2. At-plant 77 pounds/acre plus V5 @ 80 pounds (Y-Drop vs. Coulter)

3. At-plant 77 pounds/acre plus V8 urea + Agrotain (broadcast)

4. At-plant 77 pounds/acre plus V12 @ 80 pounds (Y-Drop vs. Coulter)

Broadcast Urea +

Agrotain at V-8

Deere Side-dress N Experiment 2017

July 25July 17 September 8

Corn Yield Response from Sidedress N Trial

in 2017 (LaCrosse, IN; sandy loam soil)Nitrogen Rate and Timing Total N

(lbs/acre)

Yield

(bu/acre)

Zero N except a common starter (19-17-0) 23 120 e

At-plant broadcast UAN (50%) + nothing 100 190 d

At-plant broadcast UAN + nothing 200 231 a

At-plant broadcast UAN (50%) + Y-Drop UAN (50%) at V5 180 227 ab

At-plant broadcast UAN (50%) + Coulter UAN (50%) at V5 180 221 bc

At-plant broadcast UAN (50%) + Urea Agrotain (50%) at V8 180 217 c

At-plant broadcast UAN (50%) + Y-Drop UAN (50%) at V12 180 229 a

At-plant broadcast UAN (50%) + Coulter UAN (50%) at V12 180 215 c

Sidedress UAN and Instinct™ Application

(2010-2016)

Relative N2O Losses in North American Corn Production are

Dependent on N Fertilizer Balance and Recovery Efficiency

Source: Omonode et al., Frontiers in Plant Science, 2017

In-season Soil Sampling for NO3 and NH4 after

banded N applications virtually impossible!

Recommended Sampling Positions (Depths of 0-12” plus 12-24”):

1. Iowa State (1997) A. Blackmer and R. Voss. PM-1714

24 cores per composite sample drawn from 8 positions

from the center of row in 1/8th width increments until you

get to 7/8 of the distance between any 2 corn rows.

2. Illinois N Watch: sampling using a board with 11 holes across

a single interrow, and then replicated for different

field positions (Dan Schaefer’s presentation on Dec. 13).

3. Nitrogen Advisor (sampling in row and between rows, but

always at least 6” from the N band).

In-season Soil Sampling for NO3 and NH4 after

banded N applications virtually impossible!

(example from V12 stage)

0

10

20

30

40

50

60

70

80

15 115 165 215 265 15 115 165 215 265 N

Quarter-row In-bandSoil NO3-N

(ppm)

0 100 150 200 250

Sidedress at V6

0 100 150 200 250

At-Plant

In-season Soil Sampling for NO3 and NH4 after

banded N applications virtually impossible!

(example from VT stage)

0

10

20

30

40

50

60

70

80

15

N

115

N

165

N

215

N

265

N

15

N

115

N

165

N

215

N

265

N

Quarter-row In-band

Soil NO3-N

(ppm)

0 100 150 200 250

At-Plant

0 100 150 200 250

Sidedress at V6

Critical Ear-leaf Nitrogen Concentrations (R1 stage)

for High Yield Corn (2010-2016)

Kovacs and Vyn, Agronomy J., 2017

The Choice!

Pre-Plant

Early Sidedress

Late Sidedress

as a Supplement

Conclusions: • Modern hybrids take up more total N at the same N rates, and more

post-silking than old hybrids, so there could be more yield and N

efficiencies to gain with late-split N.

• Late-split N hasn’t often increased grain yield compared to all N

applied at normal side-dress in Indiana corn-soybean situations, but

it has consistently increased plant N recovery efficiency.

• When corn plants recover more of the fertilizer N applied, one

benefit is reduced N2O emissions on both a per acre level as well as

per bushel of yield.

• More rate/timing etc. research needed on intentional late-split N

applications and multiple-position nutrient placement to increase

nutrient availability over the critical uptake periods.

• Determination of the N rate still needed for late-split N is

complicated (soil vs. plant based?).

Funding:Indiana Corn Marketing Council

Dupont-Pioneer

Dow AgroSciences (2009- )

4R Nutrient Stewardship

The Mosaic Company

Monsanto Company

Equipment:John Deere Cropping Systems Unit

Seed:Pioneer Hi-Bred, Int’l.

Monsanto

Dow AgroSciences

Acknowledgments

Thank you!

Questions?