Maize Light Interception and Grain Yield as Affected by Precision Planting
Feb 23, 2016
Maize Light Interception and Grain Yield as Affectedby Precision Planting
Precision Planting of Corn (Zea mays L.) to Manipulate Leaf Geometry
Research Questions• Can corn leaf orientation be manipulated by controlling seed position at
planting?
• Which seed position can result in across-row leaf orientation and what is the effect on emergence?
• What is the effect of leaf orientation on light interception and grain
yield ?
With-rowLeaf orientation
Across-rowLeaf orientation
U.S. Maize Production
Source: http://usda.mannlib.cornell.edu/
1940
1950
1960
1970
1980
1990
2000
2008
0
2,000
4,000
6,000
8,000
10,000
12,000
0
5
10
15
20
25
30
35
40
45
f(x) = 597.592910568347 x + 668.326079991409R² = 0.977089233076646
Corn Grain [kg/ha]
Gra
in Y
ield
(kg
ha-1
)
Sila
ge Y
ield
(Mg
ha-1
)
Capturing Solar Radiation • Y= Q x I x E x H
• Crop growth is the product of IPAR and RUE†
• Plant population
• Row spacing
• Hybrid maturity
• Canopy architecture
†Andrade et al., 1993 and Gifford et al., 1984‡Figure from Gardner et al., 1985
Maize Seed Orientation • Systematic leaf arrangement can maximize
light interception and increase yield†
• Earlier and more complete emergence when maize seed was planted with the proximal end down‡
†Peters and Woolley, 1959; Peters ,1961 ‡Patten and Van Doren, 1970
Figure: (c) Adrian Koller
FlatUpright
Experiment• 5 Dekalb hybrids
• 8 treatments
• 4 leaf stage
• 400 seeds
Experiment # 3
Treatmentseed
position and orientation
description
1 Upright, on the side , parallel to the row
2Upright, caryopsis pointed up, parallel to
the row
3Upright, caryopsis pointed down, parallel
to the row
4 Laying flat embryo up, parallel to the row
5Laying flat embryo down, parallel to the
row
6Laying flat embryo up, perpendicular to
the row
7Laying flat embryo down, perpendicular
to the row
8 Random
(c) Adrian Koller
Seed Orientation and Leaf Azimuth• Leaf azimuth and emergence was affected
by seed orientation and hybrid
• Upright and flat - 76 and 86% of plants with leaf azimuth between 60 and 90°
• Mean leaf azimuth • Upright = 64°• Flat = 67 °
Torres et al., 2011
Seed-to-Leaf Correlation
Koller, 2012
Objectives
• Evaluate the effect of seed orientation / leaf azimuth,
plant population, canopy architecture, and row
configuration on light interception, radiation use
efficiency, and grain yield of maize.
• EFAW and LCB, 2010-2012
• RCBD, 12 treatments and 3 blocks
• Across-row, and random leaf azimuths
• Seed orientation - upright, flat, and random;
• Plant population (plants ha-1);• 37050, 49400, and 61750• 49400, 74100, and 98800
• Hybrid canopy architecture;• Planophile and erectophile
Row direction
Upright Flat
Flat = across row leaf azimuth
Measurements and Analysis• Light interception (IPAR, MJ m-2)
• fPAR x TU=daily fPAR • IPAR (MJ m-2) = daily fPAR x total incident PAR
• Cumulative IPAR (CIPAR, MJ m-2)
• Grain yield (Yield, kg ha-1)
• Radiation use efficiency (RUE, g MJ-1)• RUE= grain yield / CIPAR
• ANOVA, contrasts, regression, and correlation analysis
Light Interception
• Significant treatment effect on fPAR was observed between V10 and VT growth stages
200 300 400 500 600 700 800 9000.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Uprighty = -2E-06x2 + 0.0038x - 0.603; r² = 0.79Flaty = -2E-06x2 + 0.0033x - 0.473; r² = 0.85
Thermal Units, °C d
fPA
R
Across-row leaf azimuth
Cumulative IPAR at Maturity (Plant Population)
• At physiological maturity seed oriented treatments intercepted more light than random seed placement
Upright Flat Random560
570
580
590
600
610
620
aa
b
CIPAR
Seed Orientation
CIP
AR
, MJ
m-2
LSD=8.7 MJ m-2
Grain Yield (Plant Population)
• Upright and flat out-yielded random seed orientation by 6 and 9%• Toler et al. (1999) showed a 10% yield increase for across row
2010 2011 2012 2010 2012EFAW LCB
1000
2000
3000
4000
5000
6000
7000
8000
9000
NS
**
NS
**
*Upright Flat Random
Yie
ld, k
g ha
-1
Grain Yield (Hybrid)
• Upright and flat were 10 and 6% greater than random
2010 2011 2012 2010 2012EFAW LCB
1000
2000
3000
4000
5000
6000
7000
8000
9000
NS
*NS
**
Upright Flat RandomY
ield
, kg
ha-1
Radiation Use Efficiency at Maturity (Hybrid)
Upright Flat Random0.80
0.85
0.90
0.95
1.00
1.05
1.10
1.15
1.20
1.25
a
a
a
RUE
Seed Orientation
RU
E, g
MJ
-1
LSD=0.35 g MJ-
1
• RCBD and Split-block, 12 trts and 3 reps
• Across-row, random, and with-row leaf azimuths;• Seed orientation – flat (parallel and
perpendicular to the row), and random
• Plant population (plants ha-1); • 37050 and 61750• 83980 and 98800
• Row Configuration;• Single rows• Twin rows
0.20 m
0.20 m
0.76 m
With-rowAcross-row Random
Leaf Azimuth Effect on Light Interception
• Across-row > random > with-row • Difference in fPAR between leaf
azimuths was usually greater at later vegetative stages at LCB
• No differences after V10 growth stage at Champaign
Orientation Performance• release seeds as close to the ground as possible
• cannot drop oriented seed 18" through seed tube• relative velocity between seed and ground is a challenge
• match ground speed?
0.6 GS 0.8 GS 1.0 GS 1.2 GS 1.4 GS
planting directing
Hybrid Dependence
• Performance dependent on seed shape (hybrid, grading)