Post on 06-Feb-2018
“Nitrogen Stabilizer Product Evaluations”
Paxton W. FittsTimothy W. WalkerDelta R&E Center
Contributors
• Dustin Harrell – LSU• Rick Norman – U of A• Nathan Slaton – U of A• Trenton Roberts – U of A• Jac Varco – MSU• Bobby Golden – MSU• David Franzen – NDSU• Jay Goos ‐ NDSU
Urea’s Reaction ProducesNH3 Gas
2 NH3 ammonia gas on soil surfaceor in flood
‐ H2O & CO2
CO(NH2)2 (NH4)2CO3 2 NH4+ + 2 OH‐
urea urease (pH ~ alkaline) ammonium salt in soil
Note: Urea’s reaction in soil initially is alkaline and increases soil pH causing ammonia volatilization loss if not incorporated in soil quickly.
Slide borrowed from R. Norman
Nitrogen Fertilizer Stabilizers/Additives
• NZONE/STAY‐N/N‐STAY• Ca‐Aminoethylpiperazine and Ca‐
Heterpolysaccharides• “N management aid” “reduce
nutrient loss” “maintain N levels”
• NutriSphere‐N® – 40% maleic‐itaconic co‐polymer
• “Polymer stabilizes and protects urea‐N, inhibiting volatilization and nitrification”
• Upgrade – Perploxylated phenol polymer resin mix
• “Slow release polymer blend agent”
• Agrotain®/Arborite/N‐FIXX– N‐(n‐butyl) thiophosphorictriamide, Urease inhibitor, “stabilizes N” “blocks urease” “reduces NH3 volatilization”
Ammonia Volatilization
0
2
4
6
8
10
12
0 5 10 15 20
% of a
pplied
Days
NH3 Volatilization Loss
urea
ams
agrotain
Data from Tunica clay. Dillon and Walker, unpublished
Rice Research Station – fertility and Agronomy ProjectWalker et al., unpublished data
0
5
10
15
20
25
30
0 5 10 15 20 25 30
NH3 lost (%
of N
app
lied)
Days
clay urea
clay agrotain
clay arborite
clay stay‐N
silt loam urea
silt loam agrotain
silt loam arborite
silt loam stay‐N
Lab Volatilization
Nitrogen Stabilizers/Additives
• NutriSphere‐N® –40% maleic‐itaconicco‐polymer
• “Polymer stabilizes and protects urea‐N, inhibiting volatilization and nitrification”
Lab EvaluationNutrisphere
0816243240485664
0 5 10 15
Cumulative NH3Loss
(% of a
pplied N‐fe
rtilizer)
Time (days)
Urea Agrotain+Urea Nutrisphere+Urea Ammonium Sulfate
Source: Franzen et al. (2011, in press) J. Plant Nutr.0.25% Nutrisphere added
• Perploxylated phenol polymer resin mix
• “Slow release polymer blend agent”
• “Reduces urea dissolution”
• “Reduces the potential for volatilization over the competition and untreated urea from 25 to 50% at 3‐4 qt/ton”
Lab EvaluationUpgrade
051015202530354045
0 5 10 15
Cumulative NH3Loss
(% of a
pplied N‐fe
rtilizer)
Time (days)
Urea Agrotain‐Urea Upgrade‐Urea
Source: Norman and Roberts (unpublished data)
Lab EvaluationExtend
051015202530354045
0 5 10 15
Cumulative NH3Loss
(% of a
pplied N‐fe
rtilizer)
Time (days)
Urea Agrotain‐Urea Extend‐Urea
Source: Norman and Roberts (unpublished data)
Rice Research Station – fertility and Agronomy ProjectWalker et al., unpublished data
0
5
10
15
20
25
30
0 5 10 15 20 25 30
NH3 lost (%
of N
app
lied)
Days
silt loam urea
silt loam agrotain
silt loam arborite
silt loam stay‐N
Lab Volatilization
Rice Research Station – fertility and Agronomy ProjectWalker et al., unpublished data
Lab Volatilization
0
5
10
15
20
25
30
0 3 7 10 14 17 21
%NH3 loss
Days
Urea
Agrotain Ultra 3qt
N‐FIXX 3 qt
Rice Research Station – fertility and Agronomy Project
0
5
10
15
20
25
3 6 9 12 15 18 21
NH4‐N lo
ss (%
of t
otal
applied)
Time (days)
UreaAS‐UreaASSuper‐UAgrotain‐Urea
Data provided by Dr. Dustin Harrell
Rice Research Station – fertility and Agronomy Project
i
e-h d-h
a
a-d a-da-e a-c
5000
5500
6000
6500
7000
7500
8000
8500
9000
9500
10 DPF 7 DPF 4 DPF 1 DPF
Yie
ld (l
b/A
)
Application time (Days Prior to Flooding)
UreaAgrotain-Urea
581 lbs7 %
1238 lbs15 %
Nitrogen Cycle
Urea is quickly broken down in the soil into NH3
(NH2)2CO2 + H2O → 2NH3 + CO2
NH3 undergoes further degradation
Ammonium (NH4+) Nitrite (NO2
‐)
Nitrate (NO3‐)Volatile N2 loss
Nitrosomonas
Nitrobacter
Reduction
0123456789
5.1 5.3
8.5 8.7
4.77.0
5.3
Ammonium Half‐life (days)
Fitts and Walker, 2011. Unpublished.
Grain Yield
LSD = 7Source x Timing (P = 0.0024)8218
8071
8235
7467
7642
7000
7200
7400
7600
7800
8000
8200
8400
43% Urea ENTEC
lb/A 2DBF
10DBF
LSD = 421
Data collected at DREC2010
Sharkey clay soil
Urea vs Agrium 43%
5453
7233
4273
5602
6859
5289
0
1000
2000
3000
4000
5000
6000
7000
8000
14 1
lb/acre
Days before flood
Urea 150Urea 75Agrium 150Agrium 75
LSD = 394
Special Thanks