MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 1
Apr 18, 2023
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Corn and Soybeans
Chad LeeExtension Agronomist, University of Kentucky
[email protected] www.uky.edu/Ag/GrainCrops/
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 10
Key Points
• Sharpen Your Pencils• Select good hybrids/varieties• CB hybrids for late plantings• Corn: 30,000 seeds/acre on better soils• Soybean, full season: 100,000 plants/acre• Fungicides: only when needed• Soil Test: soil-applied fertilizers
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 11
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
Pick good hybrids, good genetics
• Would you like to select the hybrids that have the best chance of performing well on your farm?
• You use 2009 and older data to predict 2010 performance.
• Does all data do this?
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CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 13
Which colors are different?
A
B
C
D
A > C > B > DSource: R.L. Nielsen
FEB 2009
CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 14
Which colors are different?
A
B
C
D
Excessive background “noise” can mask treatment effects.
Source: R.L. NielsenFEB 2009
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Is it real, or is it “noise”?
• Field research is always plagued by the confounding effects of background “noise” that tend to camouflage the effects of the treatments being evaluated. – Also referred to as “experimental error”.– Background “noise” consists of variability
among plots due to other, uncontrolled, often unknown yield influencing factors.
Source: R.L. NielsenFEB 2009
Brand HybridHyb No.
Yield, Bushels/A
20 171.97 179.7
LSD (0.05) 13.4
CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 16
Are the yields different?
FEB 2009
Brand HybridHyb No.
Yield, Bushels/A
Pioneer 31P41 20 171.9Pioneer 31P41 7 179.7LSD (0.05) 13.4
CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 17
Are the yields different?
FEB 2009
Corn Hybrid Trials, 2008
Hybrid Test No. of Hybrids,
2008
No. of Hybrids, 2 Years
No. of Hybrids, 3 Years
Early (112 or earlier) 75 24 2
Medium (113-117) 68 22 3
Late (118 or later) 11 5 2
Total 154 51 7
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 18
No. of Locations
Reps per Location
Total Plots per Hybrid
Total Plots, 2 years
Total Plots, 3 years
7 3 21 42 63
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
Corn Hybrid Trials, 2008
Hybrid Test
No. of Hybrids
2008
Within One LSD from Top
Mean Yield of
Test
Top 20% Yield Diff.
$/acre ($5
corn)
Early (112 or earlier) 75 7 189 201 12 60.00
Medium (113-117) 76 17 188 197 9 45.00
Late (118 or later) 11 3 173 186 13 65.00
Totals 162 27
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 19
Medium Maturity, 2008
YIELD MOIST STAND LODGTEST WT
BU/AC % % % LBS/BU
BRAND/HYBRID 2008 2008 2008 2008 2008
DEKALB DKC65-44 (VT3) 202.0* 17.9 99.7 4.6 55.7
LG SEEDS LG2625VT3 201.4* 17.9 100.0 3.0 55.6
DYNA-GRO 57V05 200.6* 18.2 99.9 4.5 55.5
CROW'S 5304 VT3 200.0* 17.1 99.9 7.6 56.0
BECK 6733 HXR 199.6* 18.4 98.6 7.3 55.4
TRISLER T-8N51RRCB 196.6* 17.2 98.0 5.0 56.0
CROPLAN GENETICS 7505VT3 195.7* 18.5 98.7 5.9 55.4
VIGORO V56YR82 (RR2,YGCB) 195.6* 17.6 99.7 7.1 55.7
PIONEER 33F85 (RR2) 195.5* 17.6 99.2 7.1 55.9
AUGUSTA A08-06CB 194.7* 17.4 99.8 5.3 55.9
TRISLER T-9J38RRCB 194.4* 17.6 98.3 5.1 55.8
TRISLER T-8A02CB 194.4* 17.2 99.6 6.2 56.1
AUGUSTA A08-10CB 194.4* 16.9 98.9 3.4 56.1
DAIRYLAND 9116 (GT/CB/LL) 193.7* 17.3 99.3 4.0 56.0
AGRIGOLD A6632VT3 193.6* 18.2 99.7 4.2 55.5
WYFFELS W8253 VT3 193.3* 16.7 99.8 5.7 56.3
DAIRYLAND 9313 (YGCB/RR2) 193.3* 16.6 99.3 4.8 56.2
MEDIUM AVERAGE 188.1 17.5 99.2 5.5 55.8
LSD (0.10) 9.2 0.6 2.3 0.8 0.3
Annual Summary
76 Hybrids Total
17 Hybrids within one LSD of top yield in the test.
13 Brands
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Do traits = yield?
Trait(s)No. of
EntriesCBLL 1CL 1RRHXHT 1GT 2HX 2HXLL 2HXLLRR 2GTCBLL 3HXRR 3RR2 3CB 5RRCB 10none 13VT3 28TOTAL 76
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Shelby County Corn Trial, 2008
Brand Hybrid Trait Hyb No.
Test Weight (lb/bu)
Grain Moist.
(%)Yield, Bushels/A (15.5% Moist.)#
Difference (GMO - Base) Sig. of Diff.
Ellis Choice 31P41 Base 20 61.3 10.5 171.9 Pioneer 31P41 Base 7 59.0 10.5 179.7 18.1 ***Pioneer 31P42 HX1RR2 1 60.5 11.5 197.8 Pioneer 33M54 Base 5 61.8 10.5 167.5 17.4 **Pioneer 33M57 HX1RR2 3 61.2 10.7 184.9 NK 71R7 Base 11 59.7 10.3 187.7 2.5 **NK 72Q6 CBLL 4 59.0 10.9 190.2 Crows C4846T RR2YGPL 10 58.2 10.2 209.4 25.5 **Crows C4847 Base 8 58.3 10.3 183.9 Dekalb DKC61-69 VT3 9 57.7 10.8 205.3 Dekalb DKC63-42 VT3 14 58.7 10.4 200.9 Dekalb DKC65-44 VT3 15 60.7 11.0 211.3 Garst G8348 CLLLRW 19 60.0 10.9 184.5 11.8 **NK N77-3000 GTCBLLRW 2 59.8 11.7 196.3 So. States SS647 VT3 13 58.5 10.2 196.8 17.8 nsSo. States SS777 GMO 18 58.8 10.3 179.0 Exsegen ES518 Base 12 60.0 10.6 189.8 7.1 nsWyffels W7251 VT3 6 60.0 10.4 197.0 Wyffels W8680 Base 17 58.5 10.6 194.3 3.0 **Wyffels W8681 VT3RR2YGCB 16 58.5 11.3 197.3 LSD (0.05) 1.3 0.7 13.4 CV 1.6 4.4 5.1 Average 59.5 10.7 191.3 12.9
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Insects
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 23
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
Bt’s for Corn PestsBrand Name Event(s) Gene(s)
YieldGard Corn Borer Mon810 Cry1Ab
YieldGard Rootworm Mon863 Cry3Bb1
YieldGard Plus Mon810xMon863 Cry1Ab+Cry3Bb1
Herculex 1 TC1507 -Corn Borer Cry1F
Herculex RW DAS-59122-7 Cry34Ab1+Cry35Ab1
Herculex Xtra TC1507xDAS-59122-7 Cry1F+Cry34Ab1+Cry35Ab1
Agrisure CB Bt-11 Cry1Ab
Agrisure RW MIR604 mCry3A
Agrisure CB/RW Bt-11xMIR604 Cry1AB+mCry3A
YieldGard VT RW Mon88017 Cry3Bb1
YieldGard VT Triple Mon810xMon88017 Cry1Ab+Cry3Bb1
YieldGard VT Pro Mon89034 Cry1A.105+Cry2Ab2
YieldGard VT Triple Pro Mon89034xMon88017 Cry1A.105+Cry2Ab2+Cry3Bb1
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Insects Controlled by Bt CornCB’s CEW BCW FAW CRW
YieldGard CB ++ + - + -
YieldGard RW - - - - ++
YieldGard Plus ++ + - + ++
Herculex ++ ++ ++ ++ -
Herculex RW - - - - ++
Herculex Xtra ++ ++ ++ ++ ++
Agrisure CB ++ + - + -
Agrisure RW - - - - ++
Agrisure CB/RW ++ + - + ++
YieldGard VT RW - - - - ++
YieldGard VT Triple ++ + - + ++
YieldGard VT Pro ++ ++ - ++ -
YieldGard VT Triple Pro
++ ++ - ++ ++
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YieldGard RW, Urbana, July 2, 2007: Mike Gray, Univ of IL
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MONSANTO, DOW AGREEMENT PAVES THE WAY FOR INDUSTRY’S FIRST-EVER, EIGHT-GENE STACKED OFFERING IN CORN Stacked product combines Dow AgroSciences’ and Monsanto’s insect-protection and weed control trait technologies; product set to deliver greater performance, value and options for farmers
INDIANAPOLIS and ST. LOUIS (Sept. 14, 2007) – Monsanto (NYSE: MON) and Dow AgroSciences LLC, a subsidiary of The Dow Chemical Company (NYSE: DOW), have reached a cross-licensing agreement aimed at launching SmartStax™, the industry’s first-ever eight-gene stacked combination in corn. The agreement is expected to create a new competitive standard for stacked-trait offerings and present an expanded growth opportunity for both companies’ seed brands and traits businesses by the end of the decade.
Cry1F + Cry34Ab1 + Cry35Ab1 + Cry3Bb1 + Cry1A.105 + Cry2Ab2
Roundup Ready 2 + Liberty Link
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When is Bt Corn Needed?• Bt CB –
– Late planted corn– Corn planted after May 5
• Bt RW –– Corn following corn >2 yrs
• Bt CB + RW –– When both of the above is true
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Yield Benefit by Planting Date, 6-Year Average
Planting Date Non-Bt Tunneling (in)
Yield Diff. (bu)
Early – Mid April4/5 – 4/13
3.5 3.3
Late April4/17 – 4/30
4.5 2.3
Early –Mid May5/6 – 5/13
4.6 6.6
Late May5/21 – 5/31
5.7 9.3
Early – Mid June6/5 - 6/14
6.5 20.7
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* UKREC: Herbek, Johnson, Bessin
Bt Recommendations
• When trying a new Bt hybrid– Try to get the same genetics for the refuge– Plant the refuge such that yield comparisons
are meaningful (same date, similar location)
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Seed Treatments and Vigor• In some studies, a yield bump not due to
insect protection
• Stress related genes turned on– Micro array data – drought tolerance, cold tolerance, and other
• Does not occur in all situations, not well understood
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Seed Treatments, Insects Controlled
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WW WG FB SCM BCW
CRW
Gaucho + ++ + ++ - -Prescribe ++ ++ ++ ++ - +Cruiser Ex Pak + ++ ++ ++ + -Cruiser EP CRW
++ ++ ++ ++ + ++
Poncho 250 + ++ ++ ++ + -Poncho 1250 ++ ++ ++ ++ ++ ++Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
Corn Populations
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Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
Corn Yields
• Our current population data suggests that corn yields top out around 30,000 plants/acre…on good soils.
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Corn YieldsWoodford County 2007
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Year: 2007 Location: Woodford County FarmHybrid: SS777RR2YGPLPoncho 1250-treated seedPlanting: May 3, 2007
Corn YieldsWoodford County, 2008
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Corn YieldsLexington, 2008
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Fungicides
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Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
2008, Lex1, Lex2 and Logan County(3 locations total)Averaged over Hybrids
Check Headline
Yie
ld,
bu
/a (
15
.5%
)
0
50
100
150
200
250
300
Corn Fungicides, KY, 2008
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HybridsDKC63-42DKC64-79
No-Tillage
Small Plots
Risk Assessment to Determine Likely Risk Assessment to Determine Likely Response to Foliar Fungicides in Response to Foliar Fungicides in CornCorn
Factors that Increase Risk• Susceptible hybrid (primarily GLS)• Continuous corn• No-till• Late planting• High plant population and/or yield
potential• Irrigation• Disease-favorable weather
forecasted• Disease activity at tasseling• Field history of disease and
lodging More riskResponse more likely
Less riskResponse less likely
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AGR-1 Thresholds
Crop Nutrient Soil Test Amount to Apply
Corn For Grain P2O5 >60 0
K2O >300 0
Soybean P2O5 >60 0
K2O >300 0
Corn Silage P2O5 >60 0
K2O >420 0
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Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
The effect of soil pH on the activity of soil micro-organisms, availability of plant nutrients, and occurrence of toxic elements
Corn Alfalfa
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Nitrogen Deficiency on Corn
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Nitrogen Source
Gra
in Y
ield
(bu
/a)
140
150
160
170
180
a a
a a a
b
b
b
Corn yield response to N source at the Princeton, KY location in 2007. All plots received 75 lb N/acre.
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N Volatilization Study 2007Quicksand, KY
Nitrogen Source (all trt received 120 lbs N/a)
Urea AN Agrotain ESN NSN Super Urea UAN
Cor
n Y
ield
(bu
/a)
100
120
140
160
180
200
220
c
ab
c
bc
abab
a
All treatments applied V3-4
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Princeton, 200875 lbs N/acre3/12/08 75 lbs N/acre
3/12/08
150 lbs N3/12/08 75 lbs N
5/5/08
LSD = 12 bu/acreMAR 2009 46CHAD LEE, UNIVERSITY OF KENTUCKY © 2009
Nitrogen Conclusions
1. Sidedress N applications have always been recommended for soils that are not well drained
2. Nitrogen volatilization can be a problem with urea – research result show Agrotain and ESN to be more effective than Nutrisphere
3. High yields can be obtained with relatively low rates of N if applied timely.
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Phosphorus
Soil TestPhosphorus 42 lbs/a 21 lbs/a
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Avail Polymer on Fescue (Princeton, KY)http://www.uky.edu/Ag/Agronomy/Soils/ssnv/vol27no3.pdf
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Avail Polymer on Fescue (Princeton, KY)
Second Harvest
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Avail Polymer on Fescue (Princeton, KY)
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Potassium DeficiencyMAR 2009 52CHAD LEE, UNIVERSITY OF KENTUCKY © 2009
STK = 185 STK = 202
STK = 235MAR 2009 53CHAD LEE, UNIVERSITY OF KENTUCKY © 2009
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
2008, Soybean Study
• K2SO4
– 5 lbs product /acre
– (2.5 lbs K2O)
– 3 applications
• (NH4)2SO4 – 5 lbs product/acre– (1 lb N, 1 lb S)– 3 applications
• Fungicide– One extra application
• Single field• Split in two• Same variety, planting
date, seeding rate
MAR 2009 54CHAD LEE, UNIVERSITY OF KENTUCKY © 2009
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
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2008 County Trt vs. Check(bu/acre)
Graves -8
Shelby -7
Marion -1
2008, Soybean Study
• K2SO4
– 5 lbs product /acre
– (2.5 lbs K2O)
– 3 applications
• (NH4)2SO4 – 5 lbs product/acre– (1 lb N, 1 lb S)– 3 applications
• Fungicide– One extra application
County Trt vs. Check
Graves -8
Shelby -7
Marion -1
• Single field• Split in two• Same variety, planting
date, seeding rate
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Crop Acre Yield N P K Ca Mg S Cu Mn Znbu/a
Corn 150 235 90 185 28 28 24 0.11 1.6 0.45Soybean (grain) 40 150 35 55 7 7 4 0.04 0.05 0.04
Wheat 60 105 40.5 75 10.5 13.5 12 0.6 0.38 0.3
----------------------- lbs/a ----------------------
Total Uptake of Selected Plant Nutrients
2 Qt/Acre = 5 lbs/AcreApplication Rate
Nutrient Analysis 2 qt/a 10 gal/acre% lbs/A lbs/A
N 11% 0.55 11P 5% 0.25 5K 8% 0.4 8B 0.2% 0.01 0.2Cu 0.05% 0.0025 0.05Fe 0.1% 0.005 0.1Mn 0.05% 0.0025 0.05Mo 0.005% 0.00025 0.005Zn 0.05% 0.0025 0.05
MAR 2009 60CHAD LEE, UNIVERSITY OF KENTUCKY © 2009
ZincZinc
Photo by: L. MurdockMAR 2009 61CHAD LEE, UNIVERSITY OF KENTUCKY © 2009
Corn
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Soybean Variety Trials
• MG II-III (Relative MG 2.7-3.9)
• MG EARLY IV (Relative MG 4.0-4.5)
• MG LATE IV (Relative MG 4.6-4.9)
• MG V (Relative MG 5.1-5.9)
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 64
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
Soybean Variety Trials, Full Season Soybeans
MG
No. of Varieties
2008
Within One LSD from Top
Mean Yield of
Test
Top 20% Yield Diff.
$/Acre, $8 soy
2.7-3.9 48 11 42.5 46.5 4 32.00
4.0-4.5 68 13 43.3 46.5 3.2 25.60
4.6-4.9 66 19 42.8 45.8 3 24.00
5.0-5.9 36 4 42.4 50.6 8.2 65.60
Total 218 47
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 65
LATE MG IV
YIELD (BU/AC)A LODG.
TYPE BRAND -- VARIETY 2008 07-08 06-08 2008
MATURITY GROUP LATE IV (RELATIVE MG 4.6-4.9)
* PIONEER 94Y70 46.6 1.7
* ASGROW DKB46-51 46.5 42.2 47.3 1.4
* ASGROW AG4606 46.5 1.4
* PROGENY P4908 RR 46.3 1.5
* ARMOR 48-J3 46.1 45.1 1.4
* DELTA GROW 4970 RR 45.9 40.6 47.2 1.9
* BECK 474NRR 45.7 1.3
ASGROW AG4903 45.5 42.5 48.0 1.4
* UNISOUTH GENETICS USG 74A76 45.4 42.7 48.0 1.6
* VIGORO V47N9RS 45.3 1.3
* CROW'S C4820R 45.0 1.3
* DELTA GROW 4870 RR 45.0 1.5
* SEED CONSULTANTS SCS 9479RR 45.0 1.4
* UNISOUTH GENETICS USG 74G78 45.0 1.1
EXP * NK BRAND XR4881 44.8 1.2* SOUTHERN CROSS RUFUS 4.7 N, RR, STS 44.6 1.2* PROGENY P4606RR 44.4 43.3 1.2* SOUTHERN STATES RT4808N 44.4 43.9 49.2 1.6
DAIRLYAND 8482/RR 44.4 42.0 1.5 LATE GROUP IV AVERAGE 42.8 40.8 47.2 1.4 LSD (0.10) 2.2 3.8 2.5 0.1
68 varieties total
19 within the LSD of highest yield
13 brands
1 not glyphosate-resistant
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 66
~ not Roundup Ready* Resistant to SCN
Soybean Populations
• Full Season Soybeans:– 100,000 plants/acre final stand
• Replant Full Season Soybeans– 50,000 plants/acre (uniform stand)
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 67
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
How many seeds are needed to get 100,000 plants per acre?
Seed Germ.Rate
Target Stand Seeds/Acre
Assumed Stand Loss Seeds/Acre
75% 100,000 133,333 10% 148,14885% 100,000 117,647 10% 130,71995% 100,000 105,263 10% 116,95990% 100,000 111,111 50% 222,22290% 100,000 111,111 30% 158,73090% 100,000 111,111 20% 138,88990% 100,000 111,111 10% 123,457
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 68
Hardin CountyReplicated strips 50K, 100K and 150K seeds/acre3.9 maturity, full seasonBob Wade, Back Forty Farms
52,000
150,000
100,000
55.7 bu/a55.7 bu/a 53.3 bu/a53.3 bu/a
55.6 bu/a55.6 bu/a
Back Forty FarmsHardin Countyfull season plantingReplicated strips 50K, 100K and 150K seeds/acre2006 season
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Soybean: Populations & Weeds
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MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 71
Canopy Closure
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Canopy Closure
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Soybean:Populations & Weeds• Low Weed Pressure
– No differences in canopy closure
• High Weed Pressure– Lower populations do not close canopy as
well
• Timing– 3 + 7 WAP
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 74
Corn Hybrids | Bt Corn | Corn Populations | Fungicides | Soil Fertility Soybean Varieties | Soybean Foliar Fertilizer | Soybean Populations
MAR 2009 CHAD LEE, UNIVERSITY OF KENTUCKY © 2009 75