Morteza MozaffariSoil Testing and Research Laboratory, Marianna

Immediate and Residual Effects of Urea and Pelleted Poultry Manure on Corn and Soil in Arkansas

Mississippi River Delta Region of Arkansas (MRDRA)

600,000 acres

Pelleted Poultry Litter (PPL) 3 - 4 - 3

$135/ton

Objectives

Evaluate the immediate and residual effect of urea and PPL on:

• Corn grain yield

• Corn leaf N

• N recovery by corn grain

• Mehlich-3 extractable P and K

Research Protocol• Duration: 3 yrs (2005-2007)

• 2004 crop: corn

• Soil: Loring silt loam (Oxyaquic Fragiudalfs)

• Experimental design: RCB with four replications

• Plot size: 40’ by 12.6’, four rows wide

• Standard Zn, S, pest, and irrigation mgmt.

• P or K application: None

• Corn cultivar: main season RRBt

• Planting: 7April to 17 May

• Harvest: 28 Aug to 17 SepStudy site

Experimental Treatments N-source 2005 2006 2007

----- Total N rate (lb/acre) -----

None 0 0 0

Urea 50 50 50

Urea 100 100 100

Urea 150 150 150

Urea 200 200 200

Urea 250 250 250

Urea 300 300 300

PPL 80 0 0

PPL 160 0 0

PPL 240 0 0

PPL 320 0 0

PPL 400 0 0

• Soil: Six cores/plot, 0-6” Pre application 05, preplant 07 Mehlich-3 extractable nutrients, pH, OM, NO3-N

• Ear leaf: 20 leaves/plot at silk stage Measured total N by Kjeldahl

• Corn grain: Harvested the two center rows with a plot combine Collected grain sample from each plot at harvest Measured total N by Kjeldahl

Soil and Plant Sampling and Analysis Protocols

• Analysis of Variance:– to evaluate the annual effect of urea and one time

application of PPL on soil and plant parameters

– sites were analyzed separately

• Corn grain N recovery (GNR):

Data Analysis

(Grain N uptake for that N rate – Grain N uptake at 0 N) GNR =

(Total N applied by that N rate) X (100)

Today’s TalkI. Background

II. Current status

III. Future plansResults

Interpretative guidelines for nutrient levels in Arkansas (row crops)

Soil test Level P K

-------- ppm ---------

Very Low < 16 < 61

Low 16-25 61-90

Medium 26-35 91-130

Optimum 36-50 131-175

Above Optimum > 50 > 175

Selected soil properties in 0-6” depth (spring 2005)

Mehlich-3 extractable nutrients

pH OM NO3-N K P Ca Cu Zn

% ---------------------------- mg/kg -----------------------------

6.5 1.9 6 193 70 1350 1.4 3.5

Soil test K and P were above optimum

Effect of urea and residual N from PPL on corn grain yield in 2005 G

rain

yie

ld (

bu/a

cre)

0

60

120

180

Urea PPL Control

F

E

D

BCAB

A A

EF

D

CDBCB

Means with the same letter are not statistically different at P =0.1

N rate (lb/acre)

N from urea applied in 2005 N from PPL applied in 2005

Effect of urea and residual N from PPL on corn grain yield in 2006

0

60

120

180

Urea PPL Control

N from urea applied in 2006 N from PPL applied in 2005

Gra

in y

ield

(b

u/a

cre)

EF

AABC

D

E

I I IH GH FG

N rate (lb/acre)

Effect of urea and residual N from PPL on corn grain yield in 2007

0

50

100

150

200

Urea PPL Control

N rate (lb/acre)

Gra

in y

ield

(b

u/a

cre)

H

D

CB B

A A

FGGEF E

FG

N from urea applied in 2007 N from PPL applied in 2005

Urea applied in 2006 PPL applied in 2005

N rate (lb/acre)

Effect of urea and PPL on leaf N

3.8

2.82.12.02.2

0

2

4Leaf

N (

%)

MSD 0.1=0.3

PPL applied in 2005Urea applied in 2007

4.0

2.2 2.01.92.0

0

2

4

MSD 0.1=0.3

Urea PPL applied in 2005

N rate (lb/acre)

Grain N recovery from urea and PPL

3838

2014

0

30

60

4252

640

30

60

45

61

2.45.5

0

35

70

GNR (%)

2005

2006

2007

Effect of cropping and residual P from PPL on soil test P in the 0-6” depth in spring 2007

Urea applied in 2006 PPL applied in 2005

N rate (lb/acre)

Mehlich-3 P (ppm)

0

30

60

90

120

Urea PPL Control

EDEDCE

DCC C

B

A

DE DEE

DCE

Optimum soil test P

Effect of cropping and residual K from PPL on M-3 K in the 0-6” depth (spring 2007)

Annual urea rate PPL, 2005 only

Mehlich-3 K (ppm)

EEDE

BCBCBCD

A

BA

DEECD

E DE

100

140

180

220

260

0 50 100

150

200

250

300 80 16

024

032

040

0

Urea PPL Control

Optimum soil test K

N applied from each source (lb/acre)

Conclusions • 400 lb N/acre from PPL did not produce yield significantly >

– 200 lb N/acre from urea in yr 1

– 50 lb N acre from urea in yrs 2 and 3

• In the 2nd and 3rd year:– ear leaf N concentration in plants from zero N plots, PPL treated plots,

and low urea plots were not significantly different

• Grain N recovery from PPL– yr 1: 14-29%

– yr 2: 4-6%

– yr 3: 2.5-5%

• PPL application elevated M-3 extractable P and K

Questions?

Effect of urea and residual N from PPL on N concentration in corn stover in 2006

Urea 2006 PPL 2005 only

N applied from each source (lb/acre)

Stover N (g/kg)

4

8

12

16

Urea PPL Control

AAA

BBBB B

B B B B