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FERTILIZERRESEARCH
2009Report of Progress 1031
Kansas State UniversityAgricultural Experiment Station and Cooperative
Extension Service
KANSAS
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
I
Contents
IV Introduction
V Contributors
1 PrecipitationData
2 DepartmentofAgronomy2 SoybeanResponsetoFoliarApplicationofManganeseandZinc
6 FertilizationStrategiesforIron-DeficiencyChlorosisinSoybeanProduction
11 UseofNitrogenManagementProductsandPracticestoEnhanceYieldandNitrogenUptakeinNo-TillCorn
19 UseofNitrogenManagementProductsandPracticestoEnhanceYieldandNitrogenUptakeinNo-TillGrainSorghum
25 CorrectionofPotassiumDeficiencyinSoybeanProductioninKansas
29 NitrogenFertilizationofCornUsingSensorTechnology
32 TimingofNitrogenFertilizationofCorn
35 NitrogenFertilizationofNitrogen-StressedSoybean
37 TimingofNitrogenFertilizationofWheat
39 EffectsofPhosphorusFertilizerEnhancementProductsonCorn
KANSASFERTILIZERRESEARCH
2009
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
II
42 EastCentralKansasExperimentField42 ImpactofPlantingatDifferentDistancesfromtheCenterof
Strip-TilledFertilizedRowsonEarlyGrowthandYieldofCorn
46 EffectofVariousFertilizerMaterialsonDrylandGrainSorghum
48 KansasRiverValleyExperimentField48 MacronutrientFertilityonIrrigatedCornandSoybeanina
Corn/SoybeanRotation
51 EffectofVariousFoliarFertilizerMaterialsonIrrigatedSoybean
53 SouthCentralKansasExperimentStation53 EffectsofNitrogenRateandPreviousCroponGrainYieldin
ContinuousWheatandAlternativeCroppingSystemsinSouthCentralKansas
64 SoutheastAgriculturalResearchCenter64 TillageandNitrogenPlacementEffectsonYieldsinaShort-
SeasonCorn/Wheat/Double-CropSoybeanRotation
66 EffectofNitrogenandPhosphorusStartersonShort-SeasonCornGrowninConservation-TillageSystems
69 EffectsofPlantingDate,NitrogenPlacement,andTimingofSupplementalIrrigationonSweetCorn
71 EffectsofNitrogenFertilizerandPreviousDouble-CroppingSystemsonSubsequentCornYield
74 EffectsofFertilizerNitrogenRateandTimeofApplicationonCornandGrainSorghumYields
76 EffectofPreviousCrop,NitrogenPlacementMethod,andTimeofNitrogenApplicationonNo-TillWheatYield
78 ComparisonofFertilizerNitrogenSourcesAppliedinLateWinterforNo-TillWinterWheat
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
III
80 EffectsofPhosphorusandPotassiumFertilizerRateandTimeofApplicationinaWheatDouble-CroppingSystem
82 NitrogenManagementforCrabgrassHayProduction
87 WesternKansasAgriculturalResearchCenters87 Long-TermNitrogenandPhosphorusFertilizationof
IrrigatedGrainSorghum
90 Long-TermNitrogenandPhosphorusFertilizationofIrrigatedCorn
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
IV
IntroductionThe2009editionoftheKansasFertilizerResearchReportofProgressisacompilationofdatacollectedbyresearchersacrossKansas.InformationwascontributedbyfacultyandstafffromtheDepartmentofAgronomy,Kansasagronomyexperimentfields,andagriculturalresearchandresearch-extensioncenters.
WegreatlyappreciatethecooperationofmanyK-StateResearchandExtensionagents,farmers,fertilizerdealers,fertilizerequipmentmanufacturers,agriculturalchemicalmanufacturers,andrepresentativesofvariousfirmswhocontributedtime,effort,land,machinery,materials,andlaboratoryanalyses.Withouttheirsupport,muchoftheresearchinthisreportwouldnothavebeenpossible.
Amongcompaniesandagenciesprovidingmaterials,equipment,laboratoryanalyses,andfinancialsupportwere:Agrium,Inc.;Cargill,Inc.;DeereandCompany;U.S.Envi-ronmentalProtectionAgency;FMCCorporation;FluidFertilizerFoundation;Foun-dationforAgronomicResearch;Honeywell,Inc.;HydroAgriNorthAmerica,Inc.;IMC-GlobalCo.;IMCKalium,Inc.;KansasAgriculturalExperimentStation;KansasConservationCommission;KansasCornCommission;KansasDepartmentofHealthandEnvironment;KansasFertilizerResearchFund;KansasGrainSorghumCommis-sion;KansasSoybeanCommission;KansasWheatCommission;MKMinerals,Inc.;Monsanto;PioneerHi-BredInternational;ThePotashandPhosphateInstitute;PursellTechnology,Inc.;Servi-Tech,Inc;TheSulphurInstitute;WinfieldSolutions;andU.S.DepartmentofAgriculture-AgriculturalResearchService.
SpecialrecognitionandthanksareextendedtoTroyLynnEckartofExtensionAgron-omyforhelpwithpreparationofthemanuscript;KathyLowe,MariettaJ.Ryba,andMelissaMolzahn—thelabtechniciansandstudentsoftheSoilTestingLab—fortheirhelpwithsoilandplantanalyses;andMaryKnappoftheWeatherDataLibraryforpreparationofprecipitationdata.
Compiledby:DorivarRuizDiazExtensionSpecialistSoilFertilityandNutrientManagementDepartmentofAgronomyKansasStateUniversityManhattan,KS66506-5504
KANSASFERTILIZERRESEARCH
2009
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
V
ContributorsA.Bontrager,GraduateStudent,Dept.ofAgronomy,K-StateManhattan
M.Davis,GraduateStudent,Dept.ofAgronomy,K-State,Manhattan
W.F.Heer,Agronomist-in-Charge,SouthCentralKansasExperimentField,Hutchinson
K.A.Janssen,SoilManagementandConservation,EastCentralKansasExperimentField,Ottawa
K.W.Kelley,CropsandSoilsAgronomist,SoutheastAgriculturalResearchCenter,Parsons
A.M.Liesch,GraduateStudent,Dept.ofAgronomy,K-State,Manhattan
M.B.Kirkham,Professor,CropPhysiology,Dept.ofAgronomy,K-State,Manhattan
L.D.Maddux,Agronomist-in-Charge,KansasRiverValleyExperimentField,Topeka
J.D.Matz,GraduateStudent,Dept.ofAgronomy,K-State,Manhattan
K.L.Martin,AssistantProfessor,SouthwestResearch-ExtensionCenter,GardenCity
D.B.Mengel,Professor,SoilFertility,Dept.ofAgronomy,K-State,Manhattan
J.L.Moyer,ForageAgronomist,SoutheastAgriculturalResearchCenter,Parsons
N.O.Nelson,AssistantProfessor,SoilFertility/NutrientManagement,Dept.ofAgronomy,K-State,Manhattan
D.A.RuizDiaz,AssistantProfessor,SoilFertilityandNutrientManagement,Dept.ofAgronomy,K-State,Manhattan
A.J.Schlegel,Agronomist,SouthwestResearch-ExtensionCenter,Tribune
D.W.Sweeney,SoilandWaterManagementAgronomist,SoutheastAgriculturalResearchCenter,Parsons
A.Tran,UndergraduateStudent,Dept.ofAgronomy,K-State,Manhattan
A.N.Tucker,GraduateStudent,Dept.ofAgronomy,K-State,Manhattan
N.C.Ward,GraduateStudent,Dept.ofAgronomy,K-State,Manhattan
H.S.Weber,GraduateStudent,Dept.ofAgronomy,K-State,Manhattan
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
1
Precipitation Data
Month ManhattanSWRECTribune
SEARCParsons
ECKExp.Field
Ottawa
HCExp.Field
HesstonS-------------------------------------------in.-----------------------------------------
2008August 5.29 4.79 4.79 2.82 5.17September 5.42 0.83 6.80 6.93 4.92October 2.78 2.95 3.32 4.49 4.28November 1.34 0.37 3.44 1.62 1.93December 0.64 0.33 2.18 1.57 0.35Total2008 43.25 15.37 61.69 44.70 37.61Departurefromnormal
+8.45 -2.07 +19.60 +5.49 +4.54
2009January 0.04 0.30 0.13 1.25 0.03February 0.65 0.46 1.70 1.41 0.33March 3.01 0.93 4.10 4.09 2.20April 5.25 2.17 9.95 4.37 5.79May 0.98 1.00 6.17 6.81 3.11June 8.53 1.23 4.67 9.75 5.26July 6.55 2.83 7.30 8.61 5.25August 4.50 2.22 5.56 1.01 2.04September 2.03 2.66 12.61 3.71 4.29
Month
NCKExp.Field
BellevilleKRVExp.
Field
SCKExp.Field
Hutchinson ARC-Hays---------------------------------------------in.------------------------------------------
2008August 3.67 1.40 2.29 3.40September 4.28 5.51 5.73 1.42October 8.63 3.43 5.10 6.02November 0.01 0.62 1.06 0.70December 0.41 1.06 0.37 0.24Total2008 44.18 26.52 38.59 33.70Departurefromnormal
+14.86 -5.89 +8.27 +11.07
2009January 0.02 0.03 0.04 0.45February 0.25 0.15 0.23 1.30March 0.09 2.61 1.78 0.41April 2.36 3.90 5.94 1.95May 1.93 1.25 3.91 6.85June 6.23 5.85 4.58 1.85July 4.35 5.93 2.05 4.02August 4.28 4.00 4.13 3.40September 3.00 1.41 6.79 1.42SWREC=SouthwestResearchExtension-Center;SEARC=SoutheastAgriculturalResearchCenter;ECK=EastCentralKansas;HC=HarveyCounty;NCK=NorthCentralKansas;KRV=KansasRiverValley;SCK=SouthCentralKansas;ARC=AgriculturalResearchCenter.
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2
Department of Agronomy
Soybean Response to Foliar Application of Manganese and Zinc
N.Nelson,L.Maddux,M.Davis,andA.Bontrager
SummaryThereisincreasedinterestinapplyingmicronutrientstosoybean.Theobjectiveofthisstudywastodetermineifsoybeanrespondedtofoliarapplicationsofmanganese(Mn)andzinc(Zn)appliedinvariousforms.ThestudywasconductedinarandomizedcompleteblockdesignattheAshlandBottomsandRossvilleexperimentfields.Treat-mentsincludeddifferentratesofMnandZnfoliarappliedtosoybeanatapproximatelytheV6growthstage.TreatmentsdidnotincreasetissueorgrainconcentrationsofMnorZn.Treatmentsdidnotaffectyield,moisture,ortestweight.AlthoughsoiltestZnwasnearthecriticallimitforrecommendedZnapplication,tissueZnconcentrationswereabovethecriticalvalueforplantgrowth.
IntroductionInterestinfoliarmicronutrientapplicationsonsoybeanhasrecentlyincreased.Applica-tionofthesefertilizerproductscanpotentiallybecombinedwithroutineglyphosateapplications,whichsavesonapplicationcosts.However,additionalresearchneedstobedonetodeterminetheyieldbenefitsfromthesemicronutrientapplicationsaswellasthepotentialforantagonisticeffectsoftheherbicideonnutrientabsorptionbytheplant.TheobjectiveofthisstudywastodetermineifsoybeanrespondedtofoliarapplicationsofMnandZnsuppliedinthreedifferentforms.Asecondaryobjectivewastodetermineifapplicationofmicronutrientsourcesinconjunctionwithglyphosateaffectedproductperformance.
ProceduresThestudywasconductedattheAshlandBottomsandRossvilleagronomyexperimentfieldsnearManhattanandTopeka,KS,respectively.Twostudies—fullandreduced—wereimplementedatRossville.Thegrowingseasonwasverygood;ithadadequatemoistureandcooltemperatures.Harvestwasdelayed,butthisdidnotaffectyield.Althoughirrigationwaterwasavailable,irrigationwasnotappliedbecauseoffrequentrainsthroughoutthesummer.SoilanalysesforthelocationsareinTable1.
CulturalpracticesforeachlocationarelistedinTable2.Alllocationswereconven-tionallytilledwith30-in.rows.Plotsizesateachlocationwere10ftwideby30ftlong.Treatmentswerearrangedinarandomizedcompleteblockdesignwithfourreplica-tions(Table3).FortheAshlandBottomsandRossville2studies,treatmentsweretankmixedwithglyphosateunlessotherwisenoted.Glyphosatewasapplied2daysbeforetreatmentapplicationattheRossville1study.Glyphosatewasappliedat0.75lbae/awith1.5%ammoniumsulfate.GlucoheptonatemicronutrientproductwassuppliedbyBrandtConsolidated,Inc.,andthephosphatemicronutrientproductwassuppliedbyAgro-KCorporation.
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Department of Agronomy
LeafsampleswerecollectedfromtheuppermostfullydevelopedtrifoliateatR3(July24,2009andJuly25,2009atManhattanandRossville2,respectively)andanalyzedfortotalnutrientcontent.Thecentertworowsofeachplotwereharvested,andseedsampleswereanalyzedfortotalnutrientcontentbystandardmethods.
ResultsTreatmentsdidnotsignificantlyaffectyield,testweight,moisture,orplantanalysis(Tables4,5,and6).Lackofyieldresponsedoesnotnecessarilyindicatepoorperfor-manceoftheappliednutrientsource.CriticallimitsforMnandZninsoybeantissueare17and21ppm,respectively(Belletal.,1995).Asindicatedbythenutrientconcen-trationsinplantleavesatR3,thesoybeanplantswerenotdeficientineitherMnorZn.Therefore,plantresponsewouldnothavebeenexpectedintheseconditions.ThesoiltestZnatAshlandBottomswasrightatthecriticallevelforZn(1ppm);however,micronutrientavailabilitycanbeinfluencedbymultiplefactors.Therefore,acombina-tionofsoilanalysisandtissueanalysisisrecommendedforguidanceonmicronutrientapplications.
ReferencesBell,P.F.,W.B.Hallmark,W.E.Sabbe,andD.G.Dombeck.1995.Diagnosingnutrientdeficienciesinsoybean,usingM-drisandcriticalnutrientlevelprocedures.AgronomyJournal87:859-865.
Table 1. Selected analysis for soils used in the study
LocationOrganicmatter pH
SMPbuffer
pHMehlich
III-PNH4-
OAcKDTPA
ZnDTPA
FeDTPA
Mn% ––––––––––––––ppm––––––––––––––
Manhattan 1.5 5.1 6.7 48 330 1.0 69.4 39.2Rossville 1.3 6.7 na1 16 154 na na na1na,notavailable.
Table 2. Cultural and experimental details for the three study locations
Study VarietyPlanting
date Treatments1
Treatmentapplica-
tiondate HarvestdateAshlandBottoms NKS39-A3 5/22/09 all 7/2/09 10/19/09Rossville1 Taylor398 5/23/09 all 7/2/09 10/07/09Rossville2 Taylor398 5/23/09 1,3,4,5,7 7/9/09 10/07/091SeeTable3fortreatmentdescriptions.
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Department of Agronomy
Table 3. Micronutrient products, application rates, and timingTiming Product
applicationTreatment Glyphosate1 Treatment Mn Znqt/a lb/a lb/a
1.Control V6 V6 0 0 02.Mn/Zn-Glucoheptonate V6 V6 1 0.125 0.1753.Mn/Zn-Phosphite V6 V6 1 0.05 0.0754.DelayedMn/Zn-Phosphite V6 10dayslater 1 0.05 0.0755.Experimentalproduct V6 V6 46.HighMn/Zn-Glucoheptonate V6 V6 1.5 0.2 0.37.HighMn/Zn-Phosphite V6 V6 4 0.2 0.38.DelayedMn/Zn-
Glucoheptonate V610days
later 1 0.125 0.1751FortheAshlandandRossville2locations,glyphosatewastankmixedwithalltreatmentsexcept4and8.
Table 4. Soybean leaf tissue analysis at growth stage R3, seed analysis at harvest, seed moisture, test weight, and yield as affected by treatments at Ashland Bottoms study location
Plantanalysis SeedanalysisTreatment1 Mn Zn Mn Zn Moisture Testweight Yield2
––––––––––ppm–––––––––– % lb/bu bu/a1 89.3 35.4 26.8 29.3 13.0 na3 66.02 84.9 35.6 21.8 24.3 12.7 na 67.93 82.8 33.9 25.5 27.5 12.4 na 68.64 78.3 33.9 18.0 20.3 12.6 na 68.05 81.0 34.7 19.5 22.8 12.8 na 70.66 86.1 37.2 24.8 27.3 12.7 na 70.07 83.3 38.5 23.8 27.0 12.9 na 67.88 81.3 34.3 21.0 23.0 12.7 na 67.6P-value4 0.469 0.951 0.332 0.650 0.737 0.802LSD 10.1 8.9 8.1 10.5 0.7 6.2CV(%) 8.2 15.8 33.8 34.7 3.5 6.31TreatmentnumberscorrespondtothoselistedinTable3.2Correctedto13%moisture.3na,notavailable.4FromANOVAF-testfortreatmenteffects.
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Department of Agronomy
Table 5. Soybean moisture, test weight, and yield as affected by treatments at the Rossville1 study locationTreatment1 Moisture Testweight Yield2
% lb/bu bu/a1 12.1 54.8 43.32 12.4 55.0 47.93 12.8 55.0 48.54 12.2 55.0 47.35 12.3 54.6 45.86 12.3 54.9 46.37 12.1 53.8 42.68 12.3 54.0 46.2P-value3 0.485 0.122 0.875LSD 0.8 1.1 9.3CV(%) 3.9 1.5 13.01TreatmentnumberscorrespondtothoselistedinTable3.2Correctedto13%moisture.3FromANOVAF-testfortreatmenteffects.
Table 6. Soybean leaf tissue analysis at growth stage R3, seed analysis at harvest, seed moisture, test weight, and yield as affected by treatments at Rossville2 study location
Plantanalysis SeedanalysisTreatment1 Mn Zn Mn Zn Moisture Testweight Yield2
–––––––––––ppm–––––––––– % lb/bu bu/a1 54.8 28.5 19.0 18.0 11.3 54.5 54.63 54.0 29.8 19.3 18.3 11.0 54.3 55.54 54.8 29.5 21.3 23.0 11.7 50.6 52.25 52.8 31.8 21.0 22.0 11.3 54.1 59.47 55.5 31.0 20.0 20.0 11.1 54.3 55.2P-value3 0.872 0.547 0.944 0.606 0.191 0.285 0.867LSD 5.9 4.4 7.3 8.2 0.6 4.3 14.1CV(%) 8.4 9.7 29.0 36.7 3.3 5.6 15.61TreatmentnumberscorrespondtothoselistedinTable3.2Correctedto13%moisture.3FromANOVAF-testfortreatmenteffects.
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6
Department of Agronomy
Fertilization Strategies for Iron-Deficiency Chlorosis in Soybean Production
A.M.Liesch,D.A.RuizDiaz,andK.L.Martin
SummaryIron-deficiencychlorosisisacommonyield-limitingfactorforsoybeangrownoncalcar-eoussoilwithhighpHandhasbeenreportedbymanyresearchersintheGreatPlainsandnorthcentralUnitedStates.Aparticularchallengetostudyingandmanagingiron-deficiencyexpressionisthehighleveloftemporalandspatialvariability.Insomeyears,chlorosisdevelopsduringearlygrowthstagesanddisappearsastheplantsmature.Inmoreseverecases,chlorosiscanpersistthroughouttheentireseason.Chlorosisgenerallyoccursinlocalizedareasoffieldsandfrequentlyoccursinlowareas.Thisstudyevaluatedseedcoatingandfoliarfertilizationwithchelatediron(Fe)sourcesaswellasvarietyselection.Preliminaryresultsindicatethatfoliartreatmentseemedtoeffectivelyincreaseplantgreenness,butseedcoatingincreasedyieldacrosslocations.Selectionofasoybeanvarietythatistoleranttoiron-deficiencychlorosisseemstoprovidesignificantimprovementsforchlorosismanagement.Futurestudiesshouldevaluateeffectivenessoftheseedcoatingapproachforironfertilizationmanagementfromanagronomicandespeciallyaneconomicperspective.
IntroductionSoilpropertiesassociatedwithiron-deficiencychlorosishavebeenstudiedformanyyears.However,itisnotyetclearwhichfactorsaffectiron-deficiencychlorosis.Recentresearchhasshownthatiron-deficiencychlorosismaynotalwaysoccurinapatternconsistentwithchangesinsoiltypes.Previousstudiesindicatedseveralsoilfactorsaspotentialcontributorsofiron-deficiencychlorosissymptomsincludingsoilpH,carbon-ates,ironoxideconcentrationinthesoil,DTPA-extractableiron,soilelectricalconduc-tivity,andsoilwatercontent.
Ironiscrucialtothephotosynthesisprocess,andadeficiencycreatesseverechlorosis.Inmildcases,soybeansarestuntedandyieldisdiminished.Inseverecases,manychloroticpatchesinthefieldbecomenecroticandresultinplantdeath.Thecausesofironchloro-sisarecomplex,anddeterminingthebestmanagementpracticestoaddresstheproblemisnoteasy.Soybeanlinesarebredtohavevarietalresistancetoironchlorosis.Othercontrolpracticescanincludein-fieldfoliarapplicationofironchelatesafterchlorosishasappeared.Thepurposeofthisstudywastoevaluatetheeffectivenessofdifferentmanagementscenariosinreducingtheprevalenceofironchlorosisatfourfieldloca-tionsinwesternKansas.
Specificobjectivesforthisstudywereto(1)evaluatetheeffectofdifferentironfertilizerapplicationstrategiesonsoybeanyieldonsoilswithpotentialforiron-deficiencychlo-rosis,(2)determineinteractionsbetweensoilpropertiesandironfertilizerapplicationsonsoybeanyield,and(3)evaluateeconomicreturnsduetoironfertilizerapplicationsandvarietalresistanceselection.
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
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Department of Agronomy
ProceduresThisstudywasinitiatedin2009attheSouthwestResearch-ExtensionCenterinGardenCity,KS,andtwolocationsatcooperatorfieldsinLaneCounty,KS.ThesoilinGardenCitywasaUlyssessiltloam(mesicAridicHaplustolls)with2.22%organicmatterandpH8.12.ThesoybeancropinGardenCitywasnotregularlyirrigatedandreceivedonly1acre-inchofwater.SoilattheLaneCountylocationswasaRichfieldsiltloam(mesicAridicArgiustolls)with1.87%organicmatterandpH8.23(Table1).TheLaneCountylocationsreceivedregularirrigationasneeded.
Plotswerearrangedinthefieldinarandomizedcompleteblockdesignwithfourreplications.Twosoybeanvarietieswithdifferentgenetictolerancetoironchlorosisweregrown:AG2905hasverygoodchlorosistolerance,andAG3205haslowtoler-ance.Chelatediron(FeEDDHA6%)wasusedforseedcoating.Oneoftwoironchelates(Fe-EDDHAorFe-HEDTA)wasappliedasafoliartreatmentat0.1lb/aironatapproximatelyatthe2-to3-trifoliategrowthstage,andasecondapplicationwasappliedapproximately2to4weekslaterifdeficiencysymptomsreappeared.Waterusedincluded17lbofammoniumsulfateadditiveper100galofspraysolution.
Soilsamplesfromthe0-to6-and6-to12-in.depthsweretakenfromeachindividualplotandanalyzedforroutinesoilproperties.Severalmeasurementsweremadetodocu-menttherelativeeffectivenessofeachtreatment.OverallestablishedplantpopulationwasrecordedinJulyalongwiththefirstSPADmeterreading;thesemeasurementswerefollowedbythefirstfoliarapplicationtreatment.OnAugust21,asecondSPADreadingwastakenbeforethesecondfoliarapplication.Totalplantheightwastakenatmaturity.Plantswereharvestedandthreshedbyhand,andyieldwasadjustedto15.5%moisture.Analysisincludedsoilorganicmatter,soiltestphosphorus,soiltestpotas-sium,extractablecalciumandmagnesium,totalorganiccarbon,totalnitrogen,soilpH,carbonates,electricalconductivity/solublesalts,andDTPA-extractableiron.Studyareaswerecharacterizedbysoilmapunits.
ResultsAtlocation1,therewerenosignificantdifferencesinSPADreadingsduetovariety,seedcoating,foliarapplication,orplantpopulation(Table2).Therewasasignificantdifferenceinplantheightduetoseedcoatingandvariety.TheAG3205varietyisatallervarietyand,onaverage,is10cmtallerthanAG2905.Coatedseedsresultedinamuchtallerplantheightthannontreatedseeds.InAG2905,treatedseedsresultedinplantsthatwere15cmtallerthanplantsfromnontreatedseeds.InAG3205,treatedseedsresultedinplantsthatwere10cmtallerthanplantsfromnontreatedseeds.Seedcoat-ingstronglyaffectedtotalyieldforbothvarieties.Foliarapplicationdidnotsignificantlyincreaseanyofthecropcontrolparameters.
Atlocation2,therewerenosignificantdifferencesbetweenthefoliartreatmentsandthecontrol,butseedcoatingandvarietyselectionaffectedcropparameters(Table3).PlantsfromcoatedseedshadasignificantlyhigherSPADreadingthanplantsfromnontreatedseeds(Table2).Likelocation1,therewasasignificantdifferenceinheightbetweenseedtreatmentsandbetweenvarieties.InAG2905,plantsfromtreatedseedswere12cmtallerthanplantsfromnontreatedseeds,andinAG3205,plantsfrom
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Department of Agronomy
treatedseedswere15cmtaller.Seedcoatingalsosignificantlyincreasedyield.Theseedcoatingincreasedyieldbyanaverageof18bu/ainAG2905andby11bu/ainAG3205.
Atlocation3,plantsfromnontreatedseedsfromAG2905hadahigherSPADreadingthanplantsfromtreatedseeds,butforAG3205,whichisthelesstolerantvariety,theseedcoatingsignificantlyincreasedchlorophyllreadings(Table4).PlantsofAG2905were5cmshorterthanplantsofAG3205,whichwasexpectedbecauseAG2905isashortervariety.YieldforAG3205wasonly5bu/agreaterthanthatforAG2905.TheseedcoatingdecreasedyieldofAG2905by14bu/abutincreasedyieldofAG3205by10bu/a.Thisresultcouldbeduetoalackofpopulationstandinthesouthendoftheplots,whichwasdamagedbyanimals.PartialANOVAacrosslocationsisshowninTable5.
AcknowledgementsThisprojectisfundedbytheKansasSoybeanCommission.
Table 1. Preliminary soil test results at four field locations at the beginning of the project in 2009
Location County pH P K Fe Ca CaCO3
-----------------ppm----------------- %1 Lane 8.3 19 1050 3.5 3336 4.02 Lane 8.4 20 1018 2.9 4429 7.03 Finney 8.4 27 822 3.2 4628 9.04 Riley 7.8 82 372 3.9 4028 8.8
Table 2. Grain yield, plant population, plant height, and SPAD meter readings for location 1
VarietySeed
coatingFoliar
application YieldPopulation
per25-ftrow HeightSPAD
readings
bu/a cmAG2905 Yes EDDHA 60.43 73.75 64.79 36.38
HEDTA 65.22 77.50 66.25 36.23Notreatment 58.09 79.88 68.83 35.20
No EDDHA 31.45 76.00 50.92 35.58HEDTA 29.82 76.38 51.79 35.20
Notreatment 35.20 75.75 50.75 35.48AG3205 Yes EDDHA 59.87 79.13 75.25 35.83
HEDTA 56.48 74.13 76.04 34.20Notreatment 58.69 79.13 76.29 36.80
No EDDHA 43.92 72.88 64.58 34.53HEDTA 37.42 81.25 63.58 35.38
NoTreatment 44.92 81.13 64.00 35.95
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9
Department of Agronomy
Table 3. Grain yield, plant population, plant height, and SPAD meter readings for location 2
VarietySeed
coatingFoliar
application YieldPopulation
per25-ftrow HeightSPAD
readings
bu/a cmAG2905 Yes EDDHA 56.28 79.38 64.92 31.95
HEDTA 71.24 78.63 65.67 32.28Notreatment 64.87 78.50 62.58 32.35
No EDDHA 44.09 70.63 50.83 28.65HEDTA 54.46 73.88 55.42 28.93
Notreatment 39.76 73.75 48.67 28.70AG3205 Yes EDDHA 67.33 80.75 77.67 32.43
HEDTA 60.03 81.50 75.00 33.38Notreatment 54.38 80.75 75.08 31.53
No EDDHA 46.18 73.88 61.00 29.58HEDTA 54.04 77.50 59.58 29.20
NoTreatment 48.79 76.13 59.58 29.55
Table 4. Grain yield, plant population, plant height, and SPAD meter readings for location 3
VarietySeed
coatingFoliar
application YieldPopulationper
25-ftrow HeightSPAD
readings
bu/a cmAG2905 Yes EDDHA 19.28 45.50 29.33 31.73
HEDTA 24.72 51.50 29.22 33.05Notreatment 28.54 48.17 34.67 36.23
No EDDHA 37.58 71.75 35.08 36.37HEDTA 36.46 65.63 34.50 38.40
Notreatment 41.71 66.75 36.17 38.57AG3205 Yes EDDHA 44.62 72.63 42.63 37.23
HEDTA 38.70 70.00 39.58 37.47Notreatment 41.19 71.50 40.42 36.28
No EDDHA 38.34 69.75 33.50 32.50HEDTA 23.20 63.125 33.75 34.55
NoTreatment 29.67 68.375 35.21 35.28
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Department of Agronomy
Table 5. Partial ANOVA for effect of variety, seed coating, and foliar iron application on grain yield, SPAD readings, and plant height across locationsEffect Yield SPAD Height
------------------------------P>F-------------------------Variety 0.1399 0.3622
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Department of Agronomy
Use of Nitrogen Management Products and Practices to Enhance Yield and Nitrogen Uptake in No-Till Corn
H.S.WeberandD.B.Mengel
SummaryLong-termresearchhasshownthatnitrogen(N)fertilizerisusuallyneededtoopti-mizecornproductioninKansas.ResearchhasalsoshowndifferencesintheresponsetovariousNfertilizers,products,andpractices,particularlyintheeasternportionofthestate,wheresoilandclimaticconditionscanleadtoNloss.Aprojectwasinitiatedin2008andcontinuedin2009toquantifyhowanumberofcurrentlymarketedproductsandcommonlyusedmanagementpracticesperformedatsupplyingNtono-tillcorn.Conditionsin2009attheselocationswereconduciveforNlossfromammoniavola-tilization,immobilization,anddenitrification.AsignificantresponsetoNfertilizeraswellasasignificantdifferenceinperformanceamongNfertilizers,enhancementprod-ucts,andapplicationpracticeswasobserved.UsingcurrentlyavailabletoolstoprotectNfromvolatilization,immobilization,anddenitrificationlosssignificantlyincreasedyieldsintheseexperiments.
IntroductionThepurposeofthisstudywastoevaluatetheperformanceofdifferentNfertilizerproducts,fertilizeradditives,andapplicationpracticesusedinKansasanddeterminewhetherspecificcombinationsimprovedyieldandNuseefficiencyofno-tillcorn.Thelong-termgoalofthestudywastoquantifysomeoftheserelationshipstoassistfarm-ersinselectingspecificcombinationsoffertilizerproducts,additives,andapplicationtechniquesthatcouldenhanceyieldandprofitabilityontheirfarm.Inthisstudy,fivetoolsforpreventingNlosswereexamined:(1)fertilizerplacement,orputtingNbelowsurfaceresiduetoreduceammoniavolatilizationand/orimmobilization;(2)useofthecommercialureaseinhibitorAgrotaintoblocktheureasehydrolysisreactionthatconvertsureatoammoniaandpotentiallycouldreduceammoniavolatilization;(3)useofthecommerciallyavailableadditivesAgrotainPlusandSuperU,whichcontainbothaureaseinhibitorandanitrificationinhibitortoslowtherateofammoniumconver-siontonitrateandsubsequentdenitrificationorleachingloss;(4)useofacommercialproduct,NutriSphere-N,thatclaimsureaseandnitrificationinhibition;and(5)useofapolyurethaneplastic-coatedurea(ESN)todelayreleaseofureafertilizeruntilthecropcanuseitmoreeffectively.TheultimategoalofusingthesepracticesorproductsistoincreaseNuptakebytheplantandenhanceyield.
ProceduresThisstudywasinitiatedin2008attheAgronomyNorthFarmnearManhattan,KS.Thestudywascontinuedin2009attheAgronomyNorthFarmnearManhattan,theEastCentralKansasExperimentFieldnearOttawa,KS,andtheSouthCentralKansasExperimentFieldnearHutchinson,KS.Importantfactsconcerningthestud-ies,includingsoils,plantingdates,andhybridsused,aresummarizedinTable1.Plotswerearrangedinthefieldinarandomizedcompleteblockdesignwithfourreplications.
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Department of Agronomy
Starterfertilizerwasappliedtoalltreatments,includingtheno-Ncontrol,atarateof20lb/aNasureaammoniumnitrate(UAN).StarterNwasappliedusinga2×2placementatManhattanandasasurfacebandatOttawaandHutchinson.WinterapplicationsofbroadcastureaandbroadcastESNwereappliedFebruary4atManhat-tan,February6atOttawa,andFebruary27atPartridgetodeterminetheefficienciesofNapplicationsatsuchanearlytiming.NitrogenmanagementtreatmentswereappliedinlateMayatManhattan;thiswasapproximatelytheV-2growthstage.AtOttawaandHutchinson,plantingwasdelayedbecauseofmoistsoilsandspringapplicationswereappliedatthetimeofplanting.Treatmentswereappliedatarateof60lb/aNforatotalNapplicationwithstarterof80lb/aN.Treatmentsappliedatalllocationsconsistedofacheckplot(noNapplied);broadcastgranularurea;broadcastgranularureatreatedwithAgrotain;broadcastgranularureatreatedwithSuperU(acombina-tionofAgrotainanddicyandiamide,anitrificationinhibitor);broadcast-sprayedUAN;broadcast-sprayedUAN+NutriSphere-N;broadcast-sprayedUAN+AgrotainPlus;broadcastgranularESNurea(ureacoatedwithpolyurethane);a50/50ESN/ureablend;surface-bandtreatmentsofUAN,UAN+NutriSphere-N,andUAN+Agro-tainPlus;andanonvolatileNsourceofUANcoulterbandedorammoniumnitrate.AtManhattan,thisconsistedofCoulter-bandedUANplacedapproximately2in.belowthesoilsurfaceintherowmiddleson30-in.centers;atOttawaandHutchinson,ammoniumnitratewasbroadcastasthenonvolatileNsource.Broadcastureatreat-mentsof90,120,and150lb/aNwerealsoappliedtodeterminetheNresponsefunc-tionateachlocation.
Severalmeasurementsweremadetodocumenttherelativeeffectivenessofeachtreat-ment.EarleaveswerecollectedatsilkingtodeterminerelativeNcontent.Firingratings(numberofgreenleavesremainingbelowtheear)weremadetoevaluateNstresstotheplantsapproximately10daysafterpollination.Wholeplantsamplesweretakentomeasureplant/stoverNcontentatmaturity.Tenplantswereselectedatrandomfromtheplotandcutoffatgroundlevel.Earswereremoved,remainingvegetativeportionsoftheplantswereweighedandchopped,andasubsamplewascollectedtodetermineNanddrymattercontent.AtManhattanandHutchinson,plotswerehandharvested,cornwasshelled,andsampleswerecollectedforgrainmoistureandgrainNcontent.AttheOttawalocation,cornwasmechanicallyharvested.Yieldwasadjustedto15.5%moisture.
ResultsResultsfromtheseexperimentsaresummarizedinTables2and3.
RelativelylowlevelsofNintheearleaf(lessthan2.7%N,whichissuggestedascriti-cal)suggestthe80lb/aNapplicationwasnotadequateatthesesites(Table2).ThissuboptimalNratewasselectedtoensurethatdifferencesinefficienciesbetweenproductswerenotmaskedbyoverapplicationofN.ThepotentialforNlossthroughammoniavolatilizationorimmobilizationlossofsurface-appliedNwashighatallthreesitesbecauseofmoistsoilatthetimeofapplication,gooddryingconditions,andalargeamountofcropresidueonthesoilsurface.ThisistypicalofconditionsineasternKansasmostyears,especiallywherecornisgrowninrotationsthatincludewheat.
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Department of Agronomy
AtManhattan,thebroadcasttreatmentofureaappliedatplantingperformedsignifi-cantlybetterthanthesametreatmentappliedinwinterbutwaslesseffectivethansomeofthealternativeproducts,suchasESNappliedatplanting(Table2).UseofureaseinhibitorswithureaorUANdidnotimproveperformance,thoughweatherconditionswerepresentforammoniavolatilization.Granularureawasmoreeffectivethanbroad-castUANatManhattan,likelybecausethehighlevelofsurfaceresiduewascapableofimmobilizingtheuniformlyappliedUAN.SurfacebandingdidnotimproveUANperformance,thoughcoulterbandingdid.Thebroadcasturea/ESNblendandtheurea+AgrotainPlustreatmentswerethehighestyieldingatManhattan.High-inten-sityrainfalleventsoccurred30to40daysafterfertilizerapplication,whichcreatedconditionsfordenitrificationloss.WinterapplicationsofESNwerenotaseffectiveasplantingtimeapplicationsofESNoranESN/ureablend.NutriSphere-Nwasnotbeneficialatthislocationwhenaddedtobroadcastorsurface-bandedUAN.
ResultsfromtheOttawalocationaresummarizedinTable2.YieldswerelowerthanthoseatManhattan,likelyaresultofdelayedplantingduetoheavyspringrainsandsignificantgreensnapofplantsthatoccurredwithathunderstormshortlyaftertassel-ing.Approximately30%oftheplantswerelostbecauseofstalkbreakage.PotentialforNlossduetoammoniavolatilization,immobilization,anddenitrificationwasalsohigh.EarleafNatOttawawaswellbelowthe2.7%suggestedcriticallevel.Ammoniavolatilizationwaslikelyhighatthissiteasindicatedbytheexcellentperformanceoftheammoniumnitrateapplication(nonvolatileNsource).ConditionswereexcellentforNlossfromvolatilizationanddenitrificationaswellasimmobilizationfollowingNappli-cations.SoilconditionsatthetimeofNapplicationweremoist,followedbya5-dayperiodofnorainfallandhightemperatures.Inthe3weeksfollowingfertilization,therewereseveralrainfallevents(4in.)thatcreatedconditionswithpotentialfordenitrification.Ingeneral,UANapplicationsofNseemedtobelesseffectivethanureaapplicationsregardlessofadditiveproductsused.UseofadditivesincreasedyieldsonlyslightlyatOttawain2009.Thiswaslikelyaresultofthehighdenitrificationlosspotentialoveranextendedperiodandthereducedeffec-tiveplantstandduetogreensnap.
ResultsfromHutchinsonarealsosummarizedinTable2.Yieldsweregoodatthisloca-tion;however,plantstandswerevariablebecauseoflackofseedclosureandaffectedplantmaturitythroughoutthegrowingseason.Thoughfieldvariabilityinstandanddenitrificationlikelywereresponsibleforthedifferencesinyields,thewinter-appliedureaandESNwerelesseffectivethanthespring-appliedureaandESNtreatments.NodifferenceamongNtreatmentswasobserved.
RelativeeffectivenessofdifferentNtreatmentsareshownincomparisontothestan-dardplantingtimebroadcastapplicationofureaforeachlocationinFigures1,2,and3.TheNresponsecurvefrombroadcastapplicationsofureaisshownforeachlocation.The60-lbureaapplicationrateandresultingyieldismarkedwithabrokenline.Theresultingyieldfromselectedothertreatmentsisthenshownontheresponsecurvetoestimatetheamountofureathatwouldhaveneededtobeappliedatplantingtoobtainsimilaryields.
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Department of Agronomy
Nitrogenuseefficiency(NUE),estimatedbyNrecovery,foreachsiteisshowninTable2.Worldwide,NUEincerealproductionisestimatedat35%;InKansas,anNUEof50%isusedtomakefertilizerrecommendations.AtManhattan,NUErangedfromalowof30%toahighof63%.Practicessuchasbroadcasturea,urea+SuperU,Agrotain,AgrotainPlusanduseofESNoraurea/ESNblendallgaveNUE>50%,whereasbroadcastorsurface-bandedUANwithorwithoutadditivesgaveNUE
15
De
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ro
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Table 2. Effect of nitrogen product and method of application on corn yields Manhattan2009 Ottawa2009 Hutchinson2009
Treatment TotalN YieldEarleaf
N GL1 YieldEarleaf
N GL Yield EarleafN GLlb/a bu/a % bu/a % bu/a %
Control 20 104 2.10 3.15 72 1.40 3.35 120 2.16 3Ureaatwinter 80 138 2.32 4 76 1.60 4.25 125 2.13 3.25BroadcastESN-coatedureaatwinter 80 154 2.36 4.1 84 1.62 5.25 129 2.15 3.8Urea 80 165 2.53 5.15 87 1.56 5.3 141 2.22 3.8Broadcasturea+Agrotain 80 169 2.56 5.75 89 1.61 4.95 133 2.19 4.35Broadcasturea+SuperU 80 173 2.38 4.8 91 1.81 5.4 138 2.16 3.4BroadcastESN-coatedurea 80 167 2.36 5.55 88 1.71 5.85 140 2.13 4Broadcast50%urea+50%ESNurea 80 174 2.40 5.2 82 1.80 5.3 121 2.19 3.4BroadcastUAN 80 148 2.37 4.3 81 1.49 3.8 135 2.23 4.05BroadcastUAN+AgrotainPlus 80 142 2.36 4.5 79 1.55 4.35 138 2.19 4.2BroadcastUAN+NutriSphere-N 80 149 2.34 3.65 71 1.50 4.05 143 2.29 3.55SurfacebandUAN 80 148 2.28 4.3 79 1.59 4.1 126 2.03 3.95SurfacebandUAN+AgrotainPlus 80 157 2.44 5.05 78 1.69 4.5 139 2.09 4SurfacebandUAN+NutriSphere-N 80 148 2.39 4.15 80 1.64 4.3 125 2.15 3.45CoulterbandUAN 80 162 2.35 5.35 106 1.82 5.8 145 2.22 4.65Broadcasturea 110 181 2.61 5.45 92 1.66 5.1 138 2.18 4.45Broadcasturea 130 179 2.60 6.1 96 1.76 5.8 127 2.27 4.2Broadcasturea 170 196 2.62 60 108 1.78 6.2 147 2.27 4.5LSD(0.10) 19 0.16 0.81 10 0.25 0.62 20 0.19 0.157
1GL,greenleavesbelowtheearleaf.
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16
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Table 3. Effect of nitrogen product and method of application on nitrogen uptakeManhattan2009 Ottawa2009 Hutchinson2009
Treatment TotalN GrainNTotalNUptake NUE1 GrainN
TotalNUptake NUE GrainN
TotalNUptake NUE
lb/a % lb % % lb % % lb %Control 20 0.93 66 na 0.86 44 na 1.35 95 naUreaatwinter 80 1.04 89 30 0.85 50 7 1.42 111 30BroadcastESN-coatedureaatwinter 80 1.02 98 41 0.87 54 13 1.46 116 25Urea 80 1.13 114 61 0.87 56 14 1.54 137 49Broadcasturea+Agrotain 80 1.12 117 63 0.89 59 19 1.57 130 44Broadcasturea+SuperU 80 1.10 114 60 0.87 53 11 1.57 129 42BroadcastESN-coatedurea 80 1.08 111 56 0.90 59 18 1.47 122 51Broadcast50%urea+50%ESNurea 80 1.08 111 57 0.91 52 13 1.53 115 22BroadcastUAN 80 1.04 101 44 0.88 53 11 1.58 129 42BroadcastUAN+AgrotainPlus 80 1.03 93 34 0.85 52 10 1.51 128 41BroadcastUAN+NutriSphere-N 80 0.97 81 20 0.87 48 6 1.51 127 40SurfacebandUAN 80 0.99 92 33 0.85 52 9 1.46 111 31SurfacebandUAN+AgrotainPlus 80 1.04 100 43 0.90 55 13 1.50 129 41SurfacebandUAN+NutriSphere-N 80 0.99 92 33 0.82 50 7 1.48 110 31CoulterbandUAN 80 1.07 106 46 0.89 66 27 1.58 133 47Broadcasturea 110 1.20 130 55 0.86 60 15 1.62 145 45Broadcasturea 130 1.22 129 42 0.85 60 9 1.55 129 36Broadcasturea 170 1.29 149 47 0.91 69 13 1.66 164 40LSD(0.10) 0.08 14 19 0.05 7 9 0.14 20 29
1NUE,nitrogenuseefficiency.
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
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Department of Agronomy
Tab
le 3
. Effe
ct o
f nitr
ogen
pro
duct
and
met
hod
of ap
plic
atio
n on
nitr
ogen
upt
ake
Man
hatt
an2
009
Ott
awa2
009
Hut
chin
son
2009
Tre
atm
ent
Tot
alN
Gra
inN
Tot
alN
U
ptak
eN
UE1
Gra
inN
Tot
alN
U
ptak
eN
UE
Gra
inN
Tot
alN
U
ptak
eN
UE
lb/a
%lb
%%
lb%
%lb
%C
ontr
ol20
0.93
66na
0.86
44na
1.35
95na
Ure
aatw
inte
r80
1.04
8930
0.85
507
1.42
111
30Br
oadc
astE
SN-c
oate
dur
eaat
win
ter
801.
0298
410.
8754
131.
4611
625
Ure
a80
1.13
114
610.
8756
141.
5413
749
Broa
dcas
ture
a+A
grot
ain
801.
1211
763
0.89
5919
1.57
130
44Br
oadc
astu
rea+
Sup
erU
801.
1011
460
0.87
5311
1.57
129
42Br
oadc
astE
SN-c
oate
dur
ea80
1.08
111
560.
9059
181.
4712
251
Broa
dcas
t50%
ure
a+5
0%E
SNu
rea
801.
0811
157
0.91
5213
1.53
115
22Br
oadc
astU
AN
801.
0410
144
0.88
5311
1.58
129
42Br
oadc
astU
AN
+A
grot
ain
Plus
801.
0393
340.
8552
101.
5112
841
Broa
dcas
tUA
N+
Nut
riSph
ere-
N80
0.97
8120
0.87
486
1.51
127
40Su
rfac
eban
dU
AN
800.
9992
330.
8552
91.
4611
131
Surf
aceb
and
UA
N+
Agr
otai
nPl
us80
1.04
100
430.
9055
131.
5012
941
Surf
aceb
and
UA
N+
Nut
riSph
ere-
N80
0.99
9233
0.82
507
1.48
110
31C
oulte
rban
dU
AN
801.
0710
646
0.89
6627
1.58
133
47Br
oadc
astu
rea
110
1.20
130
550.
8660
151.
6214
545
Broa
dcas
ture
a13
01.
2212
942
0.85
609
1.55
129
36Br
oadc
astu
rea
170
1.29
149
470.
9169
131.
6616
440
LSD
(0.1
0)0.
0814
190.
057
90.
1420
291 N
UE,
nitr
ogen
use
effici
ency
.
Equivilant urea rate, lb/a
0 20 40 60 80 100 120 140 160 180
Yiel
d, b
u/a
0
50
100
150
200
250
AgrotainESNWinter ureaBr UAN CB UANBlendWinter ESN80 lb urea
Figure 1. Response of no-till corn to 80 lb nitrogen applied using different products and application methods, Manhattan, 2009.
Equivilant urea rate, lb/a
Yiel
d, b
u/a
0 50 100 150 200 2500
20
40
60
80
100
120
AgrotainESNWinter urea Br UANAm. nitrateBlendWinter ESN80 lb urea
Figure 2. Response of no-till corn to 80 lb nitrogen applied using different products and application methods, Ottawa, 2009.
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Department of Agronomy
Equivilant urea rate, lb/a
Yiel
d, b
u/a
0 20 40 60 80 100 120 140 160 180 2000
20
40
60
80
100
120
140
160
AgrotainESNWinter urea Br UANAm. nitrateBlendWinter ESN80 lb urea
Figure 3. Response of no-till corn to 80 lb nitrogen applied using different products and application methods, Hutchinson, 2009.
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19
Department of Agronomy
Use of Nitrogen Management Products and Practices to Enhance Yield and Nitrogen Uptake in No-Till Grain Sorghum
H.S.WeberandD.B.Mengel
Summary Long-termresearchshowsthatnitrogen(N)fertilizerisusuallyneededtooptimizeproductionofgrainsorghuminKansas.Grainsorghumisgrownunderdrylandcondi-tionsacrossthestateandistypicallygrowninno-tillproductionsystems.Thesesystemsleavealargeamountofresidueonthesoilsurface,whichcanleadtoammoniavolatil-izationlossesfromsurfaceapplicationsofurea-containingfertilizersandimmobiliza-tionofNfertilizersplacedincontactwiththeresidue.Leachinganddenitrificationcanalsobeaproblemonsomesoils.Aprojectwasinitiatedin2008andexpandedin2009toquantifytheeffectofanumberofcommerciallyavailableproductsmarketedtoenhanceNutilizationbysorghum.Conditionsatthesitesusedvariedwidelyin2009.ConditionsthatcouldleadtoammoniavolatilizationandimmobilizationofNwerepresentatmostsites,andconditionsatsomesitescouldleadtodenitrificationandleaching.AtlocationswhereNlosslimitedyield(i.e.,ManhattanandOttawa)useoftheseproductsandpracticesenhancedyield.However,atlocationswhereNlosswasminimalorlowyieldsunrelatedtoNfertilizationlimitedNresponse(i.e.,TribuneandPartridge),useofthesepracticeswasnothelpful.
IntroductionThepurposeofthisstudywastoevaluatedifferentNfertilizers,products,andapplica-tionpracticesusedinKansasanddeterminewhetherspecificcombinationsimprovedyieldandNuseefficiencyinno-tillgrainsorghum.Thelong-termgoalofthisstudyistoquantifysomeoftheserelationshipstoassistfarmersinselectingspecificcombina-tionsthatcouldenhanceyieldandprofitabilityontheirfarm,undertheirconditions.Inthisstudy,fivetoolsforpreventingNlosswereexamined:(1)fertilizerplacement,orplacingNinbandsontheresidue-coveredsoilsurfacetoreduceimmobilization;(2)useofaureaseinhibitor(Agrotain)thatblockstheureasehydrolysisreactionthatconvertsureatoammoniaandpotentiallycouldreduceammoniavolatilization;(3)useofanadditive(AgrotainPlusorSuperU)thatcontainsbothanitrificationinhibitorandaureaseinhibitortoslowtherateofammoniumconversiontonitrateandsubsequentdenitrificationorleachingloss;(4)useofacommercialproduct(NutriSphere-N)thatclaimsbothnitrificationinhibitionandureaseinhibition;and(5)useofapolyurethaneplastic-coatedurea(ESN)todelayreleaseofureafertilizeruntilthecropcanuseitmoreeffectively.TheultimategoalofusingthesepracticesorproductsistoincreaseNuptakebytheplantandenhanceyield.
ProceduresThisstudywasinitiatedin2008andcontinuedin2009attheAgronomyNorthFarmnearManhattan,KS,theEastCentralKansasExperimentFieldnearOttawa,KS,andtheSouthCentralKansasExperimentFieldnearPartridge,KS.AnadditionalsiteattheSouthwestResearch-ExtensionCenternearTribune,KS,wasaddedin2009.Previ-
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Department of Agronomy
ouscropsonthesesitesweresoybeanatManhattan,double-cropsoybeanafterwheatatOttawaandPartridge,andwheatatTribune.SorghumhybridsDKSA54-00,P54G62,P84G62,andP86G32wereplantedMay18,May21,June25,andJune1atManhat-tan,Ottawa,Partridge,andTribune,respectively.WinterapplicationsofbroadcastureaandbroadcastESNwereappliedFebruary4atManhattan,February6atOttawaandFebruary27atPartridgetodeterminetheefficienciesofNapplicationsatsuchanearlytiming.Tribunedidnotreceivewinter-appliedtreatments.NitrogenmanagementtreatmentswereappliedfromlateMaytomid-Juneatapproximatelythesametimeasplanting.Treatmentsappliedatalllocationsconsistedofacheckplot(noNapplied);broadcastgranularurea;broadcastgranularureatreatedwithAgrotain;broadcastgranularureatreatedwithSuperU(acombinationofAgrotainanddicyandiamide,anitrificationinhibitor);broadcast-sprayedureaammoniumnitrate(UAN);broadcast-sprayedUAN+NutriSphere-N;broadcast-sprayedUAN+AgrotainPlus;broadcastgranularESNurea(ureacoatedwithpolyurethane);a50/50ESN/ureablend;surface-bandtreatmentsofUAN,UAN+NutriSphere-NandUAN+AgrotainPlus;andanonvolatileNsource.AtManhattan,thisconsistedofcoulter-bandedUANplacedapproximately2in.belowthesoilsurfaceintherowmiddleson30-in.centers.AtOttawa,Partridge,andTribune,ammoniumnitratewasbroadcastasthenonvolatileNsource.Broadcastureatreatmentsof30,90,and120lb/aNwereappliedtodefinetheNresponsecurveateachlocation.
Treatmentswerearrangedinthefieldinarandomizedcompleteblockdesignwithfourreplications.Plotsizewasfourrows(10ft)wideby50ftlong.Apreemergenceherbi-cidewasusedatalllocationstocontrolweeds.Preplantsoilsampleswerecollectedfromeachlocationtodeterminenutrientstatusofthesite.FlagleaveswerecollectedathalfbloomatalllocationsexceptPartridgeasameasureofplantNcontent.
ThemiddletworowsofeachplotweremachineharvestedatOttawaandTribune.A17.3-ftsegmentofthemiddletworowsofeachplotwashandharvestedatManhattanandPartridge.HarvestdateswereOctober5atManhattan,November6atOttawa,November24atPartridge,andDecember1atTribune.GrainsampleswerecollectedfromeachplotforgrainmoistureandNcontent.Yieldswereadjustedto13%moisture.
ResultsResultsfromtheseexperimentsaresummarizedinTable1.AsignificantresponsetoNwasobtainedinthisstudyatManhattan,Ottawa,andTribune.NoresponsetoNwasseenatPartridge,probablybecauseofthelowyieldsthatresultedfromalateplantingdateaswellasherbicidedamageatemergence.RelativelylowlevelsofNintheflagleaf(lessthan2.7%N,whichissuggestedascritical)wereobservedatManhattanandOttawa,whichsuggeststhe60lb/aNapplicationwasnotadequateatthesesites.However,increasingtheamountofbroadcastureaappliedatplantingdidnotresolvetheissue.
AtManhattan,nosignificantyieldincreasesoverthestandardpracticeofbroadcastinggranularureawereseenwiththeuseofnitrogenproducts,exceptfortheuseofESNatbothwinterandplantingtimeapplications.Broadcastandsurface-bandedUANtreat-mentswerenotstatisticallydifferent;however,thesurface-bandedUAN+AgrotaiPlus
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Department of Agronomy
andNutriSphere-NtreatmentsweresignificantlyhigherthanthebroadcastUAN+AgrotainPlusorNutriSphere-Ntreatments.
AtOttawa,winter-appliedbroadcastESNyieldedsignificantlyhigherthanwinter-appliedurea.YieldsforthebroadcastESNatplanting,broadcastESN/ureablend,andnonvolatileNtreatmentofammoniumnitratewereallsignificantlyhigherthanyieldsfromthe60-lbureatreatmentappliedatplanting.
AtPartridge,yieldswerelow,andtherewerenodifferencesintreatmentyields.AttheTribunelocation,nodifferenceamongNtreatmentswasobserved.
Figures1,2,and3demonstrateefficienciesoftheNproductsandapplicationtimingscomparedwiththestandardtreatmentofbroadcastingureaatplanting.
ThesedataclearlyshowthatinconditionswhereNlossisoccurring,suchasatManhat-tanandOttawain2009,useofproductsthatenhanceNusecanenhanceyieldwhileminimizingtotalNinputs.Usingthistypeproducttoaddressspecificconcernsorlossmechanismscanbemoreefficient,andpotentiallymorecost-effective,thansimplyincreasingNapplicationrate.
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22
De
pa
rt
me
nt
of
Ag
ro
no
my
Table 1. Effect of nitrogen product and method of application on sorghum flag leaf percentage nitrogen and yield, 2009 Manhattan Ottawa Partridge Tribune
TreatmentTotal
NFlag
leafNGrain
N YieldFlag
leafNGrain
N YieldGrain
NFlag
leafN YieldFlag
leafNGrain
N Yieldlb/a -----%----- bu/a -----%----- bu/a -----%----- bu/a -----%----- bu/a
Control 0 2.12 0.89 104 1.78 0.93 70 1.30 --- 41 2.64 1.1925 89Broadcastureaatwinter 60 2.13 0.91 123 1.84 0.92 86 1.27 --- 51 --- --- ---BroadcastESNatwinter 60 2.32 0.92 138 2.00 0.94 101 1.30 --- 43 --- --- ---Broadcasturea 60 2.31 0.92 137 1.93 0.94 96 1.29 --- 42 2.82 1.42 113Broadcasturea+Agrotain 60 2.50 0.96 144 1.98 0.94 105 1.31 --- 49 2.76 1.43 116Broadcasturea+SuperU 60 2.26 0.91 140 1.88 0.94 105 1.31 --- 46 2.75 1.42 109BroadcastESN-coatedurea 60 2.45 0.94 151 2.06 0.95 110 1.33 --- 45 2.80 1.38 105Broadcast50%urea+50%
ESNurea60 2.34 0.92 133 1.93 0.94 108 1.25 --- 42 2.82 1.40 113
BroadcastUAN 60 2.16 0.88 117 1.87 0.92 89 1.24 --- 55 2.91 1.41 112BroadcastUAN+Agrotain
Plus60 2.26 0.88 109 1.93 0.91 98 1.29 --- 56 2.88 1.39 111
BroadcastUAN+NutriSphere-N
60 2.33 0.89 120 1.87 0.95 85 1.31 --- 56 2.90 1.39 109
SurfacebandUAN 60 2.47 0.90 121 1.91 0.90 86 1.26 --- 40 2.73 1.39 106SurfacebandUAN+
AgrotainPlus60 2.35 0.92 126 1.91 0.95 84 1.35 --- 43 2.89 1.38 110
SurfacebandUAN+NutriSphere-N
60 2.43 0.93 139 1.94 0.94 89 1.28 --- 39 2.85 1.35 109
NonvolatileN 60 2.58 0.96 141 2.06 0.97 110 1.34 --- 49 2.78 1.39 107Broadcast30Urea 30 2.14 0.89 114 1.84 0.90 83 1.29 --- 52 2.80 1.35 104Broadcast90Urea 90 2.47 0.95 147 2.00 0.94 110 1.25 --- 53 2.85 1.50 111Broadcast120Urea 120 2.43 1.03 156 2.05 0.96 104 1.24 --- 54 3.05 1.55 109LSD(0.10) 0.17 0.04 10 0.16 0.05 12 0.09 --- NS 0.13 0.08 9
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu.
23
Department of Agronomy
Tab
le 1
. Effe
ct o
f nitr
ogen
pro
duct
and
met
hod
of ap
plic
atio
n on
sorg
hum
flag
leaf
per
cent
age n
itrog
en an
d yi
eld,
200
9
Man
hatt
anO
ttaw
aPa
rtrid
geT
ribun
e
Tre
atm
ent
Tot
al
NFl
ag
leaf
NG
rain
N
Yiel
dFl
ag
leaf
NG
rain
N
Yiel
dG
rain
N
Flag
le
afN
Yiel
dFl
ag
leaf
NG
rain
N
Yiel
dlb
/a---
--%---
--bu
/a---
--%---
--bu
/a---
--%---
--bu
/a---
--%---
--bu
/aC
ontr
ol0
2.12
0.89
104
1.78
0.93
701.
30---
412.
641.
1925
89Br
oadc
astu
reaa
twin
ter
602.
130.
9112
31.
840.
9286
1.27
---51
------
---Br
oadc
astE
SNat
win
ter
602.
320.
9213
82.
000.
9410
11.
30---
43---
------
Broa
dcas
ture
a60
2.31
0.92
137
1.93
0.94
961.
29---
422.
821.
4211
3Br
oadc
astu
rea+
Agr
otai
n60
2.50
0.96
144
1.98
0.94
105
1.31
---49
2.76
1.43
116
Broa
dcas
ture
a+S
uper
U60
2.26
0.91
140
1.88
0.94
105
1.31
---46
2.75
1.42
109
Broa
dcas
tESN
-coa
ted
urea
602.
450.
9415
12.
060.
9511
01.
33---
452.
801.
3810
5Br
oadc
ast5
0%u
rea+
50%
ES
Nu
rea
602.
340.
9213
31.
930.
9410
81.
25---
422.
821.
4011
3
Broa
dcas
tUA
N60
2.16
0.88
117
1.87
0.92
891.
24---
552.
911.
4111
2Br
oadc
astU
AN
+A
grot
ain
Plus
602.
260.
8810
91.
930.
9198
1.29
---56
2.88
1.39
111
Broa
dcas
tUA
N+
N
utriS
pher
e-N
602.
330.
8912
01.
870.
9585
1.31
---56
2.90
1.39
109
Surf
aceb
and
UA
N60
2.47
0.90
121
1.91
0.90
861.
26---
402.
731.
3910
6Su
rfac
eban
dU
AN
+
Agr
otai
nPl
us60
2.35
0.92
126
1.91
0.95
841.
35---
432.
891.
3811
0
Surf
aceb
and
UA
N+
N
utriS
pher
e-N
602.
430.
9313
91.
940.
9489
1.28
---39
2.85
1.35
109
Non
vola
tileN
602.
580.
9614
12.
060.
9711
01.
34---
492.
781.
3910
7Br
oadc
ast3
0U
rea
302.
140.
8911
41.
840.
9083
1.29
---52
2.80
1.35
104
Broa
dcas
t90
Ure
a90
2.47
0.95
147
2.00
0.94
110
1.25
---53
2.85
1.50
111
Broa
dcas
t120
Ure
a12
02.
431.
0315
62.
050.
9610
41.
24---
543.
051.
5510
9LS
D(0
.10)
0.17
0.04
100.
160.
0512
0.09
---N
S0.
130.
089
Equivilant urea rate, lb/a
Yiel
d, b
u/a
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
Agrotain ESN Br UAN Am. nitrateBlend 60 lb urea
Figure 1. Response of no-till grain sorghum to 60 lb N applied using different products and application methods, Tribune, 2009.
Equivilant urea rate, lb/a
Yiel
d, b
u/a
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
AgrotainESNBr UANBr UANAm. nitrateBlend Winter ESN 60 lb urea
Figure 2. Response of no-till grain sorghum to 60 lb N applied using different products and application methods, Ottawa, 2009.
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24
Department of Agronomy
Equivilant urea rate, lb/a
Yiel
d, b
u/a
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
160
180
AgrotainESNWinter ureaBr UANCB UANBlendWinter ESN60 lb urea
Figure 3. Response of no-till grain sorghum to 60 lb N applied using different products and application methods, Manhattan, 2009.
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25
Department of Agronomy
Correction of Potassium Deficiency in Soybean Production in Kansas
J.D.Matz,A.Tran,andD.B.Mengel
SummaryThisreportcoversthefirstyearofamultiyearprojectdesignedtoaddressissueswithpotassium(K)fertilizationofsoybeanandrotationalcrops.During2009,fourfieldresearchstudieswereestablished,allonfieldsinwhichsoiltestKlevelswerebelowthecurrentcriticallevelof130ppm.LatersoiltestingduringthegrowingseasonrevealedthatKlevelshadunexpectedlyincreasedwellabovethestandardcriticallevel.Byharvesttime,however,theKsoiltestlevelshadfallenbackdowntotherangeoftheinitialKbaseline,wellbelowthecriticallevelof130ppm.Ourdata,togetherwithdatacollectedbyfarmersandcropconsultants,showsignificantfluctuationinexchangeableKlevelsofupto50%onayearlyandevenmonthlybasis.ThisraisesquestionsabouthowreliablelabproceduresareinextrapolatingexchangeableK.
Inastudydesignedtoassesstheeffectofsampledryingandtemperature(factorsthatinfluenceKavailability),field-moistsampleswerecollectedandpreparedforanalysisandthenairdriedandovendriedat40°C,60°C,80°C,and100°Cforvariouslengthsoftime.Resultsshowedlessthana10%decreaseinexchangeableKduetohigh-temper-aturedrying(Figure1)buta50%changeinexchangeableKinthefieldovertime.Potassiumuptakewasmonitoredbyusingtissueanalysis.Resultsshowedthatbroadcastandhigh-ratesurface-bandapplicationsincreasedKuptakeslightlyin2009;themajor-ityofthetreatments,includingcontroltreatments,werewithinthenormalconcentra-tionrangeof1.7%to2.3%,indicatingnoKdeficienciesduringlatevegetativeandearlyreproductivegrowth.NocleareffectsofKfertilizationrateorplacementonsoybeanyieldwereobserved.Thisresearchwillcontinuein2010.
Introduction Withinthelastdecade,KdeficiencyinsoybeanhasbecomeatremendousconcernintheeasternhalfofKansas.TheKcontentofmanyKansassoilsthathadnaturallyelevatedKavailabilityhasdeclinedbecauseofcontinuouscroppingandplantinghigh-K-extractingcropssuchassoybeanwithoutreplacingtheKremoved.Themoreweath-eredsoilsinthesoutheasternpartofthestate,whichhavelowercationexchangecapac-ityandexhaustedKreserves,areencounteringincreasedoccurrenceofKdeficiency.Inaddition,theincreasedpopularityofno-tillsystemshasraisedadditionalconcernsofverticalstratificationandpositionalunavailabilityduetodrysoilconditionsthatresultinincreasedKfixationandreduceddiffusionrates.
Thisstudywasinitiatedin2009todeterminetheoverallimpactofKdeficienciesonsoybeanyieldsandwhatmanagementpracticescouldbeimplementedtoovercomeanyadverseeffects.Amainfocuswastodeterminewhichfertilizerapplicationmethods,includingbroadcastandsurfacebanding,efficientlycorrectedtheproblem.
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Department of Agronomy
ProceduresTheprojectwasconductedoncooperatingfarmers’fieldsinsoutheastKansas.FoursiteswereselectednearHallowell,KS,inCherokeeCounty.ThepredominantsoiltypeatallfourlocationswasaCherokeesiltloamwithanaverageKexchangeablelevelof145ppm.Plotswerearrangedinthefieldinarandomizedcompleteblockdesignwithfourreplications.Maturitygroup5soybeanswereplantedonJune25followingtheharvestofawheatcropataseedingrateof110,000seeds/a.FertilizerwasappliedshortlyafterplantingonJuly1usingKClasthefertilizersource.
Tendifferenttreatmentswereappliedtodouble-cropsoybean:anunfertilizedcheck;annualbroadcastapplicationattheraterecommendedbyKansasStateUniversity;annualbroadcastapplicationof30and60lb/aK2O;biannualbroadcastapplicationof60,120,and180lb/aK2O;andbiannualsurface-bandapplicationof60,120,and180lb/aK2O.SurfacebandingconsistedofapplyingalltheKClinaconcentratedband4to5in.wideimmediatelyadjacenttothecroprow.
Measurementoftreatmenteffectsincludedsoilsamplingevery1to2monthstotrackKlevels,leafKlevelsatpodsetandpodfill,soybeanyield,andgrainKlevels.Residualeffectsofthebiannualappliedtreatmentswillbemeasuredbycontinuingthestudyforasecondyear.Similarmeasurementswillbemadeontherotationalcorncrop.
ResultsPotassiumsoiltestlevelsinthefieldweresubstantiallyhigherthanexpectedfromroutinefieldsoiltestsconductedinthewinterof2007–2008(Table1).AllsitesshowedKlevelsapproximately50%higherthanthosein2007andwellabovetheacceptedcriticallevelof130ppmexchangeableK.ThefertilizerprogrampracticedbythegrowerwasthetraditionalK-Statenutrientsufficiencyprogram.Therefore,fertilizeraddedonthebasisofthe2007soiltestswouldhavebeensubstantiallylessthancropremovalandwouldnotexplainthesignificantincreases.Samplingthroughthegrowingseasonshowedthatthesehighlevelsremaineduntilmid-October,whensoiltestsagaindroppedtolevelsatorapproachingthosefoundin2007.
PotassiumuptakeintheleafwasgenerallyhighandwassignificantlyincreasedinmanytreatmentswhenKClfertilizerwasappliedbroadcastorsurfacebandedatahigherrate(Table2).TherelativelyhighlevelsfoundintheleaftissueareconsistentwithsoiltestKlevelsabovethecriticallevel,whichwereobservedthroughoutthegrowingseason.
NoconsistentresponsetoKfertilizationorplacementwasobservedintheyielddata(Table3).TheSWBrownandSEBrownlocationsyielddatadidshowsomesignificantdifferencesthatweareattributingtoharvestlostduetosoybeanlodgingissuesratherthantoatreatmenteffect(Table3).
Thesignificantfindingsofthisfirstyears’datarelatetothelargechangeinsoiltestKlevelsseenbetween2007and2009andatthefinalsamplingin2009.Itwillbeimpor-tanttounderstandthemechanismresponsibleforthesechangesandwhattriggersthesechangesbeforeroutinemanagementrecommendationscanbedeveloped.
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Department of Agronomy
Table 1. Soil test exchangeable potassium results at different sampling dates by siteLocation Nov.30,2007 July30,2009 Aug.31,2009 Oct.13,2009
------------------------------ppm------------------------------SWJennings 90 140 136 104SEBrown 88 155 162 109SWBrown 106 155 165 112Delmont 99 157 144 96
Table 2. Potassium in soybean leaf tissue at pod set (early) and pod fill (late) by treat-ment and site
SWJennings SEBrown SWBrown DelmontTreatment1 Early Late Early Late Early Late Early Late
-------------------------------%----------------------------Control 1.68 0.99 1.75 0.99 1.79 1.03 1.76 1.00BRK-State 1.75 1.09 1.75 0.95 1.82 1.11 1.75 1.02BR30 1.75 1.05 1.78 0.98 1.85 1.10 1.78 1.10BR60 1.79 1.10 1.79 1.02 1.87 1.09 1.78 1.09BR60,biannual 1.74 1.11 1.80 1.00 1.86 1.09 1.80 1.09BR120,biannual 1.77 1.14 1.84 1.03 1.85 1.15 1.76 1.16BR180,biannual 1.85 1.11 1.95 1.03 1.96 1.20 1.94 1.21SB60,biannual 1.82 1.20 1.80 0.98 1.84 1.09 1.85 1.07SB120,biannual 1.80 1.11 1.83 1.01 1.91 1.14 1.77 1.17SB180,biannual 1.81 1.19 1.84 1.06 1.87 1.15 1.88 1.14LSD(0.05) 0.10 0.11 0.19 0.09 0.13 0.11 0.15 0.15
1Treatments:annualbroadcast(BR)applicationattheK-State-recommendedrateand30and60lb/aK2O;bian-nualapplicationat60,120,and180lb/aK2O;andbiannualsurfaceband(SB)applicationof60,120,and180lb/aK2O.
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Department of Agronomy
Table 3. Influence of potassium fertilizer rate and treatment on soybean yield by loca-tion, 2009Treatment1 SWJennings SEBrown SWBrown Delmont
------------------------------bu/a------------------------------Control 39 36 29 38BRK-State 37 32 36 38BR30 39 37 34 37BR60 39 31 35 36BR60,biannual 41 39 36 34BR120,biannual 38 32 34 36BR180,biannual 41 33 30 38SB60,biannual 39 36 31 38SB120,biannual 40 33 34 39SB180,biannual 39 31 36 34LSD(0.05) NS 8 6 NS
1Treatments:annualbroadcast(BR)applicationattheK-State-recommendedrateand30and60lb/aK2O;bian-nualapplicationat60,120,and180lb/aK2O;andbiannualsurfaceband(SB)applicationof60,120,and180lb/aK2O.
y = -6.4857x + 251.98 R = 0.90177
0 20 40 60 80
100 120 140 160 180 200 220 240 260
Moist Air dry 40°C 60°C 80°C 100°C
K le
vel,
ppm
Figure 1. Effect of drying and drying temperature on exchangeable potassium, SW Brown location, 2009.
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29
Department of Agronomy
Nitrogen Fertilization of Corn Using Sensor Technology
A.N.TuckerandD.B.Mengel
SummaryLong-termresearchshowsthatnitrogen(N)fertilizerisgenerallyneededtooptimizecornyieldsinKansas.Cornisfairlysusceptibletoenvironmentalstresses;thus,grainyieldsandnitrogendemandcanbehighlyvariablefromyeartoyear.Also,optimumNratesarevariablebecauseofdifferencesinresidualsoilNlevels,variationsinNminer-alizationfromsoilorganicmatterandpreviouscropresidue,Nloss,andgrainyield.Duringtheperiodofthisstudy(2007–2009),optimumNratesvariedfromlocationtolocation.Useofsensortechnologyatlateside-dressingtimewaseffectiveatestimatingyieldpotentialandNneedsofcorn.
IntroductionThisstudywasinitiatedin2007todeterminetheeffectivenessofactivesensortechnol-ogiesatestimatingNneedsandresponseofcorn.Sensortechnologyhasbeensuccess-fullyusedtomakein-seasonNrecommendationsforseveralcrops,includingwinterwheat,grainsorghum,andcotton.However,workwithcornhasbeenlesssuccessful.
ProceduresThestudywasconductedattheKansasRiverValleyExperimentFieldnearRossville,KS,from2007to2009,SouthwestResearch–ExtensionCenternearTribune,KS,from2007to2009,andNorthwestResearch–ExtensionCenternearColby,KS,from2008to2009.NitrogenfertilizertreatmentsattheColby,Rossville,andTribunesitesconsistedofratesof0,100,140,and180lb/aNwithapplicationtimingsofallpreplantorasplitapplication.Inaddition,threevariableratetreatmentsdevelopedonthebasisofrecentlydevelopedcropsensortechnologies(GreenSeeker;NTechIndustries,Ukiah,CA)and/orachlorophyllmeterwereused.TheRossvillelocationhadadditionaltreat-mentsdevelopedbyusingtheCropCirclesensor(HollandScientific,Lincoln,NE)withandwithoutachlorophyllmeter.AtotalpreplantNapplicationof120lb/aNwasusedwiththesesensor-basedtreatments,theopticalsensors(GreenSeekerandCropCircle)wereusedtoestimateyieldpotentialattheV8orV9growthstage,andaddi-tionalNwasappliedaccordinglyonthebasisoftheOklahomaStateUniversitysensor-basedN-ratecalculatorfortheU.S.GrainBelt.
ThechlorophyllmeterwasusedtomeasuregreennessoftheplotrelativetothatofthehighestpreplantNplots.Whentheplotofinteresthadarelativegreennesslessthan95%or90%ofthereference,anadditional30or60lb/aN,respectively,wasapplied.AllpreplantNtreatmentswereappliedimmediatelybeforeplanting,whereasside-dresstreatmentswereappliedattheV8orV9growthstage.Allplotsreceived20lb/aNasstarterappliedwiththeplanterandwereirrigatedasneeded.Atalllocations,a200lb/aNpreplanttreatmentservedasthereferencestripforsensing.CornwasplantedinlateAprilorearlyMaywithahybridadaptedtothatarea.Normalizeddiffer-encevegetationindexwascollectedwithaGreenSeekersensorattheV9growthstage.
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30
Department of Agronomy
Thecentertworowsofeachplotwereharvestedafterphysiologicalmaturity.Grainyieldwasadjustedto15.5%moisture.
Additionalstudieswereconductedonfarmers’fieldsnearSt.Marys,KS.Sensor-basednitrogentreatmentswereappliedneartheV16growthstagewithahigh-clearancesprayerequippedwithGreenSeekersensorsandoperatedbyJ.B.PearlofSt.Marys.Thesefieldsweresplitinhalfwithhalfmanagedaccordingtothesensor-basedtreat-mentsandtheotherhalfmanagedbythefarmer.Fieldswereharvestedwithacombineequippedwithyieldmonitorsafterphysiologicalmaturity.
DatafromallexperimentswereanalyzedstatisticallyusingSASversion9.1andthePROCGLMprocedurewithanalphalevelof0.05forallmeanseparations.
ResultsFertilizingaccordingtosensortechnologyresultedingoodperformanceatColby,Rossville,andTribuneandonthefarmers’fieldsnearSt.Marys(Tables1,2,3,and4).Atalllocations,sensor-basedtreatmentsperformedstatisticallyaswellasthehighestpreplantNratebutappliedsignificantlylessN.TheseresultsindicatesensortechnologyhaspotentialtomakeappropriatemidseasonNrecommendationsforcornfromtheV8toV16growthstages.
AcknowledgmentsWethankDrs.RobertAiken,LarryMaddux,andAlanSchlegelfortheirhelpwiththisprojectandtheCornCommissionandKansasFertilizerResearchFundforfinancialsupportofthiswork.WealsothankHowardParr,JimGentry,andFrancisKelseyforhostingexperimentsontheirfarmsandJ.B.PearlandCo.forsharingdataontheirrecentexperienceswithsensortechnology.
Table 1. Effect of nitrogen fertilization on corn grain yields, Colby, 2008–2009Preplant Starter Side-dress Total Yield
-------------------------------------lb/a----------------------------------- bu/a0 20 0 20 139b100 20 0 120 171a140 20 0 160 178a180 20 0 200 176a40 20 60 120 163a60 20 80 160 182a80 20 100 200 187a100 20 GreenSeeker 136 170a100 20 CropCircle 133 175a100 20 SPAD 128 166a100 20 GreenSeeker+SPAD 148 168a100 20 CropCircle+SPAD 140 167a
MeansfollowedbythesameletterarenotsignificantlydifferentatP
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Department of Agronomy
Table 2. Effect of nitrogen fertilization on corn grain yields, Rossville, 2007–2009Preplant Starter Side-dress Total Yield
-----------------------------------lb/a----------------------------------- bu/a0 20 0 20 102d100 20 0 120 214c140 20 0 160 218bc180 20 0 200 230ab40 20 60 120 219bc60 20 80 160 229ab80 20 100 200 229ab100 20 GreenSeeker 145 222ab100 20 CropCircle 149 235a100 20 SPAD 133 215bc100 20 GreenSeeker+SPAD 126 225abc100 20 CropCircle+SPAD 145 222abcMeansfollowedbythesameletterarenotsignificantlydifferentatP
32
Department of Agronomy
Timing of Nitrogen Fertilization of Corn
A.N.TuckerandD.B.Mengel
SummaryNitrogen(N)lossisanimportantproblemincornproductionineasternKansas.ManyfarmersquestionwhethercornwillrespondtoadditionofNfertilizerslateinthegrowingseason.In2009,aseriesoffieldplotswasestablishedtoaddressthisques-tion.ResultsindicatethatgoodresponsefromNapplicationduringthelatevegeta-tivegrowthstage(V16,the16-leafstageorjustpriortotassel)canbeobtained.ThisprovidesnewopportunitiestomakeNapplicationstocorrectNdeficienciesthatcandevelopbecauseofdenitrificationorleachingduringwetyears.Italsosuggeststhatuseofopticalsensorsmountedonhigh-clearancesprayerscouldbeeffectivelyusedtomakesite-specificNapplicationlateinthegrowingseasontofinetuneNapplicationsystems.
IntroductionResearchhasshownthatNfertilizerisgenerallyneededtooptimizecornyieldsinKansas,thoughtheoptimumratevarieswidelyacrosslocationsandyears.OptimumNratesvaryforanumberofreasons,includingcropyieldandNuptake,residualNfrompreviouscropspresentinthesoilatplanting,variationsinorganicNmineralizedfromsoilorganicmatterandcropresidue,andNlossduringthegrowingseason.
Duringthepastfewyears,alargeamountofcornintheeasternpartofKansashasbeendeficientinNbecauseofin-seasonNloss.Thisstudywasinitiatedin2009todeterminetheeffectivenessofNapplicationtimingoncorngrainyieldsand,inparticular,whethercornwillrespondtolate-seasonNfertilizerapplications.
ProceduresThisstudywasconductedattheKansasStateUniversityAgronomyNorthFarminManhattan,KS,theKansasRiverValleyExperimentFieldnearRossville,KS,andontwofarmers’fieldsnearSt.Marys,KS.Initialapplicationsof60lb/aNweremadeatorshortlybeforeplanting(ureaatManhattanandRossvilleandanhydrousammoniaattheSt.Maryssites).CornwasplantedinlateAprilorearlyMaywithahybridadaptedtothatarea.NitrogenfertilizertreatmentsconsistedoffourratesofN(0to90lb/aN)asureaappliedattheV8andV16growthstagesatManhattanandonlyattheV16growthstagesattheRossvilleandSt.Maryslocations.
Plotswerearrangedinthefieldinarandomizedcompleteblockdesignwithfourrepli-cations.Thecentertworowsofeachplotwereharvestedbyhandafterphysiologicalmaturity,andcornwasdriedandshelled.Grainyieldwasadjustedto15.5%moisture.
DatawereanalyzedstatisticallywithSASversion9.1andthePROCGLMprocedurewithanalphalevelof0.05forallmeanseparations.
ResultsSignificantNresponseswereseenattheManhattanandRossvillesites,butthefarm-ers’fieldsdidnotrespondtoadditionalN(Tables1and2).AtManhattan,delayingN
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Department of Agronomy
fertilizationtotheV16growthstageproducedhighergrainyieldsthanapplyingNattheV8growthstageatthetwohighestNrates.ThisislikelyduetodenitrificationlossthatoccurredaftertheV8growthstage.Delayingapplicationsanadditional30daysreducedNloss,resultinginhigheryields.
AtRossville,cornwasNstressedatthetimeofNapplication.Althoughaportionofthisstresswasovercomebythelate-seasonfertilizerapplication,yieldswerestillsubstantiallylowerthanthoseofadjacentcornthatreceivedadequateNearlierinthegrowingseasonanddidnotdemonstrateNstress.
Atthetwofarmers’fields,noNstresswasobservedthroughouttheseason,andnoresponsetolate-seasonNwasobserved.ThisdemonstratesthatconsiderableNcanbesuppliedbythesoil,evenonsandysoilswithrelativelyloworganicmatter.
ApplyingNlateinthevegetativegrowthperiodofcorncanbeausefultoolforover-comingearlyseasonNdeficiencyandminimizingNlossduringearlierperiodsofvegetativegrowthonsoilswithhighpotentialforNloss.However,forthispracticetobesuccessful,adequateNmustbeavailableduringkeyearlygrowthstagestosupportearandkerneldifferentiation.
AcknowledgmentsWethankDr.LarryMaddux,KelseyFarms,GentryFarms,andJ.B.PearlCo.fortheirhelpwiththisproject.
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Table 1. Effect of timing of nitrogen fertilization on corn grain yields, Manhattan, 2009
StarterN PreplantN V10N V16N TotalNGrainyield
------------------------------lb/a------------------------------ bu/a20 0 0 0 20 95f20 40 0 0 60 133e20 40 30 0 90 158d20 40 60 0 120 173cd20 40 90 0 150 185bc20 40 0 30 90 166d20 40 0 60 120 192ab20 40 0 90 150 207aMeansfollowedbythesameletterarenotsignificantlydifferentatP
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Department of Agronomy
Nitrogen Fertilization of Nitrogen-Stressed Soybean
A.N.TuckerandD.B.Mengel
SummaryPlantingsoybeanwithoutinoculationintosoilswheresoybeanhasneverbeengrowncanresultinpoornodulationandnitrogen(N)deficiency.Similarproblemscanoccurwheninoculationfailsorseverelyacidsoilslimitnodulation.Inthesesituations,farm-ersoftenwonderifsoybeanwillrespondtoNfertilizers.In2009,anopportunityarosetostudythissituationbecauseofafailureofinoculationinafieldwithnohistoryofsoybeanproduction.SignificantandeconomicresponsestoNfertilizerwereobtained,uptothemaximumrateof120lb/aNapplied.
IntroductionWhenadequatelevelsofactive,appropriaterhizobiabacteriaarepresentinthesoil,soybeanplantswillnodulateandfixnitrogenandnormallynotrespondtoapplicationsofNfertilizer.Whensoybeanisplantedintogroundthathasnohistoryofsoybeanproductionoralongintervalbetweensoybeancrops,naturallevelsofrhizobiamaynotbepresentforsuccessfulnodulationandNfixation,andthecropwillbeNdeficient.Commercialinoculantsareusuallyappliedtotheseedtosupplyneededrhizobiaandprovideadequatenodulation.
In2009,soybeanplantedinto“virgin”soybeangroundorreturnedconservationreserveprogramgroundinnorthcentralKansasfieldswasobservedtobepoorlynodulatedandNdeficient,eventhoughtheseedwasproperlyinoculatedwithcommercialinoculants.Afieldstudywasestablishedinoneofthosefieldstodeterminewhethertheunnodu-latedsoybeanplantswouldrespondtoappliedNfertilizersand,ifso,howmuchcouldsuccessfullybeused.
ProceduresThisstudywasconductedonafarmer’sfieldnearSolomon,KS,thathadanotice-ablyN-deficientsoybeancrop.SoybeanvarietyNKS39-A3wasplantedno-tillintosorghumresiduefromthepreviousyearonMay20,2009,at140,000seeds/a.Aliquidinoculantwassprayedonthesoybeanseedsastheywereloadedintotheplanter.Thisfieldhadnohistoryofsoybeanproduction.NitrogenfertilizerwasappliedonJuly20,2009,tosoybeandisplayingN-deficiencysymptomsattheR1toR2growthstages.AsimpleN-ratestudywithfiveNratesrangingfrom0to120lb/aNwaslaidoutinthefieldinarandomizedcompleteblockdesignwithfourreplications.TheNwasappliedasureabysurfacebandingthematerialbetweenthesoybeanrows.RainfalloccurredwithinafewhoursofNapplication.
Thetwocenterrowsofthefourrowplotsweremachineharvestedatmaturity.Grainmoisturewasadjustedto13%moisturecontent.DatawereanalyzedstatisticallywithSASversion9.1andthePROCGLMprocedurewithanalphalevelof0.05forallmeanseparations.
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Department of Agronomy
ResultsResultsaresummarizedinTable1.Therewasanear-linearsignificantresponsetoNatthislocation.The120lb/aNratehada21bu/ayieldadvantageovertheunfertilizedcheck.Fertilizationwasclearlyeconomicalinthissituation.AdditionalresearchwillbeconductedtofurtherrefineappropriateNratesifopportunitiesdevelopinthefuture.
AcknowledgmentsWethankTomMaxwell,agricultureandnaturalresourcesagentintheK-StateResearchandExtensionCentralKansasDistrict,forhishelpwiththisproject.
Table 1. Effect of nitrogen fertilization on yield of nitrogen-deficient soybean, 2009NRate Yield
lb/a bu/a0 28d
30 37c60 42b90 43b
120 49aMeansfollowedbythesameletterarenotsignificantlydifferentatP
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Department of Agronomy
Timing of Nitrogen Fertilization of Wheat
A.N.TuckerandD.B.Mengel
SummaryLong-termresearchshowsthatnitrogen(N)fertilizermustbeappliedtooptimizeproductionofwinterwheatinKansas.Wheatisgrownthroughoutthestatewithmultipleplantingdates,followingmultiplecrops,andwithbothtillageandno-till.Becauseofenvironmentalconditions,sometimeswheatdoesnotgetfertilizedatopti-mumtimes.ThisstudycomparestheeffectsoflateNfertilizationwithnormalapplica-tiontimingsonwheatgrainyieldandproteincontentatlocationswherewheatwasplantedwithandwithoutfall-appliedstarterN.Grainyieldsforthisstudyrangedfrom49to84bu/a,whereasproteincontentrangedfrom9.3%to13.3%.Ingeneral,slightdecreasesinyieldandincreasesinproteincontentwereobservedasNapplicationwasdelayed.
IntroductionThisstudywasconductedin2009attheKansasStateUniversityAgronomyNorthFarmnearManhattan,KS.TheobjectivewastoevaluatetheresponseofwheattoNfertilizationatFeekes4,5,7,and9growthstagesatlocationswherefallNhadbeenappliedandwherenofallNhadbeenapplied.GrainyieldandproteinlevelswereusedtomeasuretheresponsetoNapplicationtiming.
ProceduresHardredwinterwheatvarietySantaFewasno-tillplantedintosoybeanstubbleat90lb/ainlateOctoberwithaCrustBusterno-tilldrill.FortypoundsofP2O5wereappliedwiththedrillinfurrowatseeding.Nitrogenwasappliedbytreatment.ActualtreatmentsusedarelistedinTable1,buttheseincluded0or30lbNinthefallandtopdressratesappliedinthespringatFeekes4,5,7,or9.Thecenter5ftofeachplotwasmachineharvestedafterphysiologicalmaturitywithaplotcombine,andgrainyieldwasadjustedto12.5%moisture.
DatawereanalyzedusingSASversion9.1andthePROCGLMprocedurewithanalphalevelof0.05forallmeanseparations.
ResultsGrainyieldandproteinvalueswereincreasedwithNfertilizer(Table1),buttheresponsewaslimited.IncreasingNratesabove30lb/aNgenerallywasnotproduc-tiveatthissite.However,proteincontentincreasedwithincreasingNrateandwithlaterapplications.Thehighestproteinlevelswerefoundwith90lbtotalNwith60lbappliedatFeekes7orFeekes9.
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Department of Agronomy
Table 1. Effect of nitrogen timing and rate on wheat grain yield and protein content, 2009
FallNFeekes
4NFeekes
5NFeekes
7NFeekes
9N TotalN Yield Protein---------------------------------lb/a--------------------------------- bu/a %
0 0 0 0 0 0 49h 9.3h120 0 0 0 0 120 78abcd 12.3bcd0 30 0 0 0 30 70defg 10.3g0 60 0 0 0 60 84ab 10.5fg0 90 0 0 0 90 77bcde 11.6cde0 0 30 0 0 30 83ab 11.2ef0 0 60 0 0 60 85a 11.6de0 0 90 0 0 90 81abc 12.4bc30 0 0 0 0 30 80abc 10.5fg30 30 0 0 0 60 74cdef 10.2g30 60 0 0 0 90 83ab 11.5e30 0 0 60 0 90 79abc 12.9ab30 0 0 0 30 60 70efg 11.7cde30 0 0 0 60 90 65g 13.3aMeansfollowedbythesameletterarenotsignificantlydifferentatP
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Department of Agronomy
Effects of Phosphorus Fertilizer Enhancement Products on Corn
N.C.WardandD.B.Mengel
SummaryFieldstudieswereestablishedinspring2008toevaluatetheperformanceoftwowidelymarketedproductsthatclaimtoenhanceavailabilityofsoilorfertilizerphosphorus(P):Avail,aPfertilizerenhanceraddedtocommercialfertilizer,andJumpStart,aseedinoculantthatinfectscornrootsandenhancesavailabilityofnativesoilP.Thisstudywascontinuedin2009atfivelocationsacrossnorthcentralandnortheasternKansas.AllfivesiteshadsoiltestPlevelsbelowthecurrentcriticallevelof20ppmandwouldhavebeenexpectedtorespondtoapplicationofPfertilizers.
Excellentcornyields,above200bu/a,wereobtainedatfourofthefivesites.However,significantresponsestoappliedPwereobtainedonlyatScandia.NosignificantincreaseinyieldduetotheuseofAvailorJumpStartwasseenatanysitewherePresponsewasobserved.
IntroductionInrecentyears,thevolatilepriceofPfertilizershascreatedinterestamongproducersinusingproductstoenhancetheefficiencyoffertilizersbeingapplied.ThisprojectwasdevelopedtotesttwosuchproductswidelyadvertisedinKansas:Avail,along-chainorganicpolymercreatedtoreducefixationoffertilizerPbyaluminumandcalcium,andJumpStart,aPenicilliam bilaiiseedinoculantthatincreasesavailabilityofnativesoilPtoplantroots.
ProceduresThisstudywasestablishedatfivelocationsinnortheasternandnorthcentralKansas:Manhattan(Readingsiltloam),Scandia(Cretesiltloam),Rossville(Eudorasandyloam),Ottawa(Woodsonsiltloam),andSilverLake(Rossvillesiltloam).TheRossville,Scandia,andSilverLakelocationsreceivedsupplementalirrigationduringthegrowingseason.Mehlich-3Psoiltestsateachsitewere:Manhattan,13ppm;Scandia,14ppm;Rossville,15ppm;Ottawa,11ppm;andSilverLake,13ppm.
Alllocationswereplantedwithhybridsadaptedtotheareaatpopulationsappropriatetotherespectivesoilsandcroppingsystems.
Plotswerearrangedinthefieldinarandomizedcompleteblockdesignwithfourrepli-cations.Therewere14totaltreatmentsconsistingoffourratesofPfertilizer(0,10,20,and40lb/aP2O5broadcastappliedasmonoammoniumpolyphosphate;MAP)withandwithoutadditionofAvailPenhancerwitheachofthefertilizer/AvailtreatmentsplantedwithorwithouttheJumpStartseedtreatment.NoJumpStarttreatmentswereappliedatSilverLake.BroadcastfertilizertreatmentswereappliedbyhandbeforeplantingusingMAPandMAPcommerciallyimpregnatedwithAvail,obtainedlocally.AllPtreatmentswerebalancedfornitrogenwithurea,whichwasbroadcastbeforeplanting.Atotalof160lb/aNwasapplied.
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Department of Agronomy
WholeplantsamplesweretakenatapproximatelytheV4growthstage,andearleafsamplesweretakenatgreensilk.DrymatteraccumulationandPuptakewerecalculatedatthetimesofwholeplantsampling.EarleafsampleswereanalyzedforPconcentra-tiononly.Resultsoftheplantanalysesarenotincludedinthisreport.Atharvest,yield,moisture,andPcontentofthegrainweremeasured.Allyieldswerecorrectedto15.5%grainmoisture.
AtOttawa,significantdamagetoallplotsoccurredbecauseofgreensnapfromaseverethunderstormthatoccurredattheV16-V18growthstage.Nearlyallplantswerelodged,andapproximately30%werebrokenatthebase.Theunbrokenplants“goose-necked”backupandproducedears.
ResultsIndividualtreatmentmeansforeachlocationandstatisticalanalysesusingplannedcomparisonsandcontrastsarereportedinTable1.InitialpreplantsoiltestsindicatedlowavailablePatalllocations.AresponsetoappliedP,asindicatedbythecontrastnoPvs.P,wasobservedonlyatScandia.NoresponsetoappliedPwasobservedattheotherlocations,eventhoughthesoiltestswerebelowthecritical20ppmlevel.OnepossibleexplanationforthislackofresponsetoappliedPisthegoodgrowingcondi-tionsandadequatesoilmoisturethroughoutthegrowingseason.Phosphorusisknowntomovetotherootforuptakethroughthesoilsolutionbydiffusion.Increasingsoilmoistureresultsinagreaterportionofsoilporesfilledwithwater;thiscreatescontinu-ouswaterfilmsfromsoilparticlesurfacestotherootsurface,reduci