influence of late-season foliar nitrogen applications on grain protein in winter wheat
DESCRIPTION
Influence of Late-Season Foliar Nitrogen Applications on Grain Protein in Winter Wheat. C.W. Woolfolk, W.R. Raun, G.V. Johnson E.G. Krenzer, and W.E. Thomason. Oklahoma State University Department of Plant and Soil Sciences. Introduction. - PowerPoint PPT PresentationTRANSCRIPT
Influence of Late-Season Influence of Late-Season Foliar Nitrogen Applications Foliar Nitrogen Applications
on Grain Protein in Winter on Grain Protein in Winter WheatWheat
Influence of Late-Season Influence of Late-Season Foliar Nitrogen Applications Foliar Nitrogen Applications
on Grain Protein in Winter on Grain Protein in Winter WheatWheat
C.W. Woolfolk, W.R. Raun, G.V. Johnson E.G. Krenzer, and W.E. Thomason
C.W. Woolfolk, W.R. Raun, G.V. Johnson E.G. Krenzer, and W.E. Thomason
Oklahoma State UniversityOklahoma State UniversityDepartment of Plant and Soil SciencesDepartment of Plant and Soil Sciences
Oklahoma State UniversityOklahoma State UniversityDepartment of Plant and Soil SciencesDepartment of Plant and Soil Sciences
IntroductionIntroductionIntroductionIntroduction Increasing grain protein in higher yielding wheat
varieties while maintaining yields is often difficult Efficient utilization of nitrogen fertilizers is imperative
for human nutrition (Smil 1997) Grain protein increases occur when foliar nitrogen is
applied at anthesis and rapidly declines before or after that time (Finney et al., 1957)
Gaseous nitrogen losses from wheat leaves occurs between anthesis and maturity (Harper et al., 1987)
Maximum N accumulation generally occurs at flowering
Increasing grain protein in higher yielding wheat varieties while maintaining yields is often difficult
Efficient utilization of nitrogen fertilizers is imperative for human nutrition (Smil 1997)
Grain protein increases occur when foliar nitrogen is applied at anthesis and rapidly declines before or after that time (Finney et al., 1957)
Gaseous nitrogen losses from wheat leaves occurs between anthesis and maturity (Harper et al., 1987)
Maximum N accumulation generally occurs at flowering
ObjectivesObjectivesObjectivesObjectives
To determine the effects of late-season nitrogen applications at four rates and two N sources on:
grain yield grain protein straw yield straw N
To determine the effects of late-season nitrogen applications at four rates and two N sources on:
grain yield grain protein straw yield straw N
Materials and MethodsMaterials and MethodsMaterials and MethodsMaterials and Methods
Application type simulated aerial 175 ml mechanically pressurized spray bottles
Nitrogen source Urea Ammonium Nitrate: no dilution-28% N Ammonium Sulfate: 700g in 1,000ml H20-11%N
Wheat (Triticum aestivum L.) “Tonkawa” hard red winter
Cropping system conventional tillage
Application type simulated aerial 175 ml mechanically pressurized spray bottles
Nitrogen source Urea Ammonium Nitrate: no dilution-28% N Ammonium Sulfate: 700g in 1,000ml H20-11%N
Wheat (Triticum aestivum L.) “Tonkawa” hard red winter
Cropping system conventional tillage
Materials and MethodsMaterials and MethodsMaterials and MethodsMaterials and Methods
Experimental sites: Efaw, OK and Perkins,OK Experimental design: RCBD, 4 replications
Plot size: 7.43 m2
N Source and rate: UAN: 0, 11, 22, 33, 44 kg N ha-1 AS: 22 kg N ha-1
Timing of application: Pre-flowering: Feekes 10.5 Post-flowering: Feekes 10.5.4
Experimental sites: Efaw, OK and Perkins,OK Experimental design: RCBD, 4 replications
Plot size: 7.43 m2
N Source and rate: UAN: 0, 11, 22, 33, 44 kg N ha-1 AS: 22 kg N ha-1
Timing of application: Pre-flowering: Feekes 10.5 Post-flowering: Feekes 10.5.4
Feekes growth Feekes growth stages instages incereal grainscereal grainsLarge, 1954Large, 1954
Feekes growth Feekes growth stages instages incereal grainscereal grainsLarge, 1954Large, 1954 10.510.5
PrePre10.5.410.5.4 PostPost
Materials and MethodsMaterials and MethodsMaterials and MethodsMaterials and Methods
Treatment N Source N-rate(kg ha-1)
Time of Application
1 ----- 0 Check2 UAN 11 Pre-flowering3 UAN 22 Pre-flowering4 UAN 33 Pre-flowering5 UAN 44 Pre-flowering6 AS 22 Pre-flowering7 UAN 11 Post-flowering8 UAN 22 Post-flowering9 UAN 33 Post-flowering
10 UAN 44 Post-flowering11 AS 22 Post-flowering
Treatment N Source N-rate(kg ha-1)
Time of Application
1 ----- 0 Check2 UAN 11 Pre-flowering3 UAN 22 Pre-flowering4 UAN 33 Pre-flowering5 UAN 44 Pre-flowering6 AS 22 Pre-flowering7 UAN 11 Post-flowering8 UAN 22 Post-flowering9 UAN 33 Post-flowering
10 UAN 44 Post-flowering11 AS 22 Post-flowering
Treatment structure employed at both sites for both yearsTreatment structure employed at both sites for both years
Gra
in y
ield
, kg
G
rain
yie
ld,
kg
h
ah
a-1-1
Pro
tein
, %
Pro
tein
, %
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
12
13
14
15
16
17
18
19
20
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
N rate, kg haN rate, kg ha--
11
Efaw 1998Efaw 1998
SED=220
SED=0.22
0
500
1000
1500
2000
2500
3000
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
Gra
in y
ield
, kg
G
rain
yie
ld,
kg
h
ah
a-1-1
12
13
14
15
16
17
18
19
20
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
Pro
tein
, %
Pro
tein
, %
Perkins 1998Perkins 1998
SED=0.53
SED=302
N rate, kg haN rate, kg ha--
11
0500
100015002000250030003500400045005000
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
12
13
14
15
16
17
18
19
20
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
Gra
in y
ield
, kg
G
rain
yie
ld,
kg
h
ah
a-1-1
Pro
tein
, %
Pro
tein
, %
N rate, kg haN rate, kg ha--
11
Efaw 1999Efaw 1999
SED=213
SED=0.52
0
500
1000
1500
2000
2500
3000
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
12
13
14
15
16
17
18
19
20
0.0 11.2 22.4 33.6 44.8
UAN-PreUAN-PostAS-PreAS-Post
Gra
in y
ield
, kg
G
rain
yie
ld,
kg
h
ah
a-1-1
Pro
tein
, %
Pro
tein
, %
N rate, kg haN rate, kg ha--
11
Perkins 1999Perkins 1999
SED=380
SED=0.92
Significant increases due to foliar applied N Grain yield
1 out of 4: UAN-linear (post-flowering, Efaw 1999)
UAN-quadratic (pre-flowering, Efaw 1999)
Straw yield 1 out of 4: UAN-quadratic (pre-flowering, Efaw 1998)
Straw N 2 out of 4: UAN-linear (post-flowering, Perkins 1998)
UAN-linear (pre-flowering, Perkins 1999)
Significant increases due to foliar applied N Grain yield
1 out of 4: UAN-linear (post-flowering, Efaw 1999)
UAN-quadratic (pre-flowering, Efaw 1999)
Straw yield 1 out of 4: UAN-quadratic (pre-flowering, Efaw 1998)
Straw N 2 out of 4: UAN-linear (post-flowering, Perkins 1998)
UAN-linear (pre-flowering, Perkins 1999)
ResultResultss
ResultResultss
Significant increases due to foliar applied N Grain protein
1 out of 4: AS (pre and post-flowering, Perkins 1998)
3 out of 4: UAN-linear (pre-flowering; 33 kg ha-1)
4 out of 4: UAN-linear (post-flowering; 33 kg ha-1)
Significant increases due to foliar applied N Grain protein
1 out of 4: AS (pre and post-flowering, Perkins 1998)
3 out of 4: UAN-linear (pre-flowering; 33 kg ha-1)
4 out of 4: UAN-linear (post-flowering; 33 kg ha-1)
ResultResultss
ResultResultss
Increased grain protein was observed at 33 kg N ha-1 in three out of four experiments when N was applied pre-flowering (2.05%)
Increased grain protein was observed at 33 kg N ha-1 in all experiments when N was applied post-flowering (1.57%)
In general, grain yield, straw yield, and straw N were not affected by foliar N applications
Foliar N applications prior to or immediately following flowering may significantly enhance protein contents
Increased grain protein was observed at 33 kg N ha-1 in three out of four experiments when N was applied pre-flowering (2.05%)
Increased grain protein was observed at 33 kg N ha-1 in all experiments when N was applied post-flowering (1.57%)
In general, grain yield, straw yield, and straw N were not affected by foliar N applications
Foliar N applications prior to or immediately following flowering may significantly enhance protein contents
ConclusioConclusionsns
ConclusioConclusionsns
UAN@28% N: $0.48/kg N x 33 kg N/ha (Post) = $16/ha
Aerial application: = $ 9/ha Total application cost = $25/ha
12% protein: $106.50/ton x 2.688 tons/ha (Avg) = $286/ha
14% protein: $124.90/ton x 2.688 tons/ha (Avg) = $336/ha
Difference = $50/ha
$25/ha profit
UAN@28% N: $0.48/kg N x 33 kg N/ha (Post) = $16/ha
Aerial application: = $ 9/ha Total application cost = $25/ha
12% protein: $106.50/ton x 2.688 tons/ha (Avg) = $286/ha
14% protein: $124.90/ton x 2.688 tons/ha (Avg) = $336/ha
Difference = $50/ha
$25/ha profit
Applied CalculationApplied CalculationApplied CalculationApplied Calculation
Future ResearchFuture ResearchFuture ResearchFuture Research
More in-depth focus on post-flowering More in-depth focus on post-flowering applicationsapplications
Alternative methods for increasing yield Alternative methods for increasing yield while increasing protein-(KHwhile increasing protein-(KH22POPO44) applied ) applied
to delay senescenceto delay senescence Focus on products which decrease N Focus on products which decrease N
losses and can be applied simultaneously losses and can be applied simultaneously with foliar N applicationswith foliar N applications
More in-depth focus on post-flowering More in-depth focus on post-flowering applicationsapplications
Alternative methods for increasing yield Alternative methods for increasing yield while increasing protein-(KHwhile increasing protein-(KH22POPO44) applied ) applied
to delay senescenceto delay senescence Focus on products which decrease N Focus on products which decrease N
losses and can be applied simultaneously losses and can be applied simultaneously with foliar N applicationswith foliar N applications
