To quantify the impact of nitrogen and potassium fertiliser on wheat yield and quality, after mouldboard ploughing non-wetting soils in the Geraldton Port Zone.
To determine the most effective way to apply nutrients (granular, banded, top dressed or liquid) on non-wetting soils after amelioration, in the Geraldton Port Zone.
Key messages
A high application of potassium (K), 25 kg/ha and standard nitrogen (N) rates, 70 kg/ha improved wheat yield and grain quality up to 0.47 t/ha on mould boarded deep sand.
In the presence of adequate potassium (> 40-50 mg/kg), in favourable seasons, wheat can respond to the application of N) fertiliser, resulting in high yield and protein. Where K is limited, returns from N are likely to be poor.
The results indicate that a higher rate of K than banding 11 kg/ha K can lead to a significant increase in yield and profitability.
Lead research organisation
Liebe Group
Host research organisation
N/A
Trial funding source
GRDC LIE00010-A
Related program
N/A
Acknowledgments
Thank you to the Hunt family for hosting this site at their Marchagee property. The Liebe Group would also like to acknowledge the project team, including Stephen Davies (DPIRD) and James Easton (CSBP) who assisted with the development of the trial design and interpretation of results. Thanks are also extended to Andrew Van Burgel (DPIRD for statistical analysis and support and the field team at Department of Primary Industries and Regional Development (DPIRD) Geraldton for implementation, management and harvesting of this trial.
This project has been supported by the GRD investment LIE00010-A Best bet management for ameliorated non-wetting soils of the Geraldton Port Zone.
Peer review: Dr Frances Hoyle, University of Western Australia
Trial results Soil test results Treatment 1, Marchagee, 19th March 2018
#
Treatment 1
Organic carbon (%)
Colwell phosphorus (mg/kg)
Water droplet penetration time (seconds)
pH CaCl2 (pH)
Electrical conductivity (dS/m)
NH4 (mg/kg)
NO3 (mg/kg)
Depth (cm)
Colwell Potassium (mg/kg)
PBI (unit)
MED (unit)
1
█
Std N No K
0.58
28
0
5.3
0.047
2
18
0-10
21
11.5
0
2
█
Std N No K
0.55
22
4.9
0.028
<1
9
10-20
19
12.9
3
█
Std N No K
0.32
24
4.5
0.017
<1
3
20-30
17
10.5
4
█
Std N No K
27
4.7
30-40
12
5
█
Std N No K
23
4.7
40-50
4
Colwell phosphorus mg/kg
Electrical conductivity dS/m
NH4 mg/kg
NO3 mg/kg
Organic carbon %
pH CaCl2 pH
Water droplet penetration time seconds
Trial results Soil test results Treatment 9, Marchagee, 19th March 2018
#
Treatment 1
Organic carbon (%)
Colwell phosphorus (mg/kg)
Water droplet penetration time (seconds)
pH CaCl2 (pH)
Electrical conductivity (dS/m)
NH4 (mg/kg)
NO3 (mg/kg)
Depth (cm)
Colwell Potassium (mg/kg)
PBI (unit)
MED (unit)
1
█
Residual Very High K
0.53
68
0
5.2
0.044
1
15
0-10
25
9.4
0
2
█
Residual Very High K
0.55
22
5.2
0.03
<1
11
10-20
17
11.9
3
█
Residual Very High K
0.3
18
4.6
0.017
<1
4
20-30
15
8.6
4
█
Residual Very High K
19
4.4
30-40
12
5
█
Residual Very High K
18
4.6
40-50
4
Colwell phosphorus mg/kg
Electrical conductivity dS/m
NH4 mg/kg
NO3 mg/kg
Organic carbon %
pH CaCl2 pH
Water droplet penetration time seconds
Trial results Impact of fertiliser management strategy on 2018 wheat protein (lowest to highest)
#
Treatment 1
Hectolitre weight (kg/hL)
Protein (%)
Screenings (%)
Grain yield (t/ha)
Grade (grade)
Applied nitrogen (kg N/ha)
Phosphorus (kg/ha)
1
█
Std N No K
11.9de
11.9de
4.5bc
1.34a
H2
70
0
2
█
Std N Std K
11.0cd
2.6a
1.68de
APW1
70
11
3
█
Liquid K
13.3fg
5.4c
1.32a
AUH2
70
11
4
█
Std N High K
10.9c
2.3a
1.81ef
APW1
70
25
5
█
No N
8.1a
3.4ab
1.50bc
ASW1
0
25
6
█
Low N
9.5b
2.7a
1.60cd
ASW1
31
25
7
█
High N
12.5ef
2.8a
1.86f
H2
100
25
8
█
High N No K
13.9g
5.4c
1.36ab
AUH2
100
0
9
█
Residual Very High K
11.0cd
2.8a
1.72def
APW1
70
Residual
Grain yield t/ha
Applied nitrogen kg N/ha
Grade grade
Hectolitre weight kg/hL
Phosphorus kg/ha
Protein %
Screenings %
Trial results Gross margin analysis by treatment
#
Treatment 1
Gross margin ($/ha)
Grain yield (t/ha)
Grade (grade)
Gross return ($/ha)
Applied nitrogen (kg N/ha)
Potassium (kg/ha)
Phosphorus (kg/ha)
Banded (kg/ha)
Banded (L/ha)
Nitrogen application (Z23) (L/ha)
Nitrogen application (Z32) (L/ha)
1
█
Std N No K
360
1.34
H2
522
70
12
0
85 Agstart Extra
54 Flexi N
83 Flexi N
2
█
Std N Std K
446
1.68
APW1
621
70
12
11
100 K-Till Extra
50 Flexi N
83 Flexi N
3
█
Liquid K
305
1.32
AUH2
488
70
12
11
85 Agstart Extra
117 Flexi NK
83 Flexi N
4
█
Std N High K
476
1.81
APW1
669
70
12
25
100 K-Till Extra/28
50 Flexi N
83 Flexi N
5
█
No N
439
1.5
ASW1
510
0
12
25
62 Big Phos/51 MoP
6
█
Low N
408
1.6
ASW1
544
31
12
25
100 K-Till Extra/28
50 Flexi N
7
█
High N
486
1.86
H2
725
100
12
25
100 K-Till Extra/28
50 Flexi N
83 Flexi N
71 Flexi N
8
█
High N No K
290
1.36
AUH2
503
100
12
0
85 Agstart Extra
54 Flexi N
83 Flexi N
71 Flexi N
9
█
Residual Very High K
343
1.72
APW1
636
70
12
99
85 Agstart Extra
54 Flexi N
83 Flexi N
Grain yield t/ha
Applied nitrogen kg N/ha
Grade grade
Gross margin $/ha
Gross return $/ha
Phosphorus kg/ha
Potassium kg/ha
Climate
Derived climate information
No observed climate data available for this trial. Derived climate data is
determined from trial site location and national weather sources.
WA
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to
construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol
16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.
