Assessing the effect of varying P and seeding rates and N rich strips

CC BY 4.0

Research organisaton
Funding source

Trial details

Researcher(s) Peter Baines (P Baines Agronomy)
Jason Collier (Rand Fertilizers Ltd)
Nicole Dimos (SPAA)
Paul Ianson (P Baines Agronomy)
John Sykes (John Sykes Rural Consulting)
Year(s) 2011
Contributor Society of Precision Agriculture Australia
Trial location(s) Rand, NSW
Assessing the effect of varying P and seeding rates and N rich strips locations
  • To compare the effects of variable rate P and seeding rate on the yield of wheat.
  • To assess if remote sensing using a Crop Circle and/or satellite maps can determine if there are difference between the treatments.
  • To assess if N rich stripes and remote sensing using NDVI and satellite map can be used as an aid to better assess the requirement for N in crop.
Key messages

There was a visual response to P applied at sowing and up until after Z31. This did not translate into yield at harvest. There was an inital response to varying seeding rate but this was not obvious at Z31 and did not translate into a yield response. The results may have been a reflection of the dry spring and the time of application. The addition of P therefore resulted in the loss of money. There was no visual response to applying N in the N rich strip in either zone. DSN results and yield targets assessed using weather prediction and the French and Schultz model were therefore used to determine a single rate of N for all plots in both zones of 3.5 t/ha. The harvest results showed no response in the N rich strip but as these were only 80 metres wide and had additional N at Z31, the result may not be a reliable guide to whether there was a response at the site. There was no response to N at harvest. Overall the yield was disappointing and well below the target and the quality was also below the target.

Lead research organisation Society of Precision Agriculture Australia
Host research organisation N/A
Trial funding source GRDC SPA000010
Related program N/A

This project was funded by the Grains Research and Development Corporation (GRDC)

Other trial partners Roy and Leanne Hamilton (Property owner's)
Download the trial report to view additional trial information


Crop type Wheat
Treatment type(s)
  • Fertiliser: Rate
  • Sowing: Rate
Trial type Precision agriculture
Trial design Unknown,Not applicable

Rand 2011

Sow date 12 May 2011 12 May 2011
Harvest date Not specified
Plot size Not specified
Plot replication Not specified

P (0, 30, 50, 75 and 100 kg/ha as MAP) applied at sowing


Glyphosate and Trifluralin applied to all plots

Download the trial report to view additional method/treatment information

Download results

Trial results Table 1

# Treatment 1
Plant density (plants/m2) Screenings (%) Moisture (%) Tillers (no./m2) Protein (%) Grain yield (t/ha) Test weight (kg/hL)
1 Seed @ 70kg/ha, MAP @ 50kg/ha 124 1.2 9.1 447 10.4 3.1 80
2 Seed @35kg/ha, MAP @ 50kg/ha 65 1.5 8.9 321 11.2 3.2 80
3 Seed @ 50kg/ha, MAP @ 50kg/ha 74 1.5 9 422 11.1 3.1 81
4 Seed @ 70kg/ha, MAP @ 0kg/ha 117 2.9 8.9 265 10.9 2.9 80
5 Seed @ 70kg/ha, MAP @ 30kg/ha 131 3 8.9 463 11.1 2.9 80
6 Seed @ 70kg/ha, MAP @ 50kg/ha 128 2.6 9 455 11.1 2.9 80
7 Seed @ 70kg/ha, MAP @ 75kg/ha 119 2.6 9 466 11.1 2.9 80
8 Seed @ 70kg/ha, MAP @ 100kg/ha 133 2.6 9 421 11.4 2.9 81

Grain yield t/ha


Moisture %


Plant density plants/m2


Protein %


Screenings %


Test weight kg/hL


Tillers no./m2

Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Rand, NSW Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Rand, NSW Sodosol
Soil Moisture Source: BOM/ANU
Average amount of water stored in the soil profile during the year, estimated by the OzWALD model-data fusion system.
Year Rand NSW
2011 577.7mm
2010 593.0mm
2009 532.8mm
2008 527.6mm
2007 504.1mm
2006 537.7mm
2005 554.5mm
2004 469.5mm
2003 434.0mm
2002 416.2mm
2001 463.4mm
2000 475.6mm
National soil grid Source: CSIRO/TERN
NOTE: National Soil Grid data is aggregated information for background information on the wider area
Actual soil values can vary significantly in a small area and the trial soil tests are the most relevant data where available

Soil properties



Derived climate information

No observed climate data available for this trial.
Derived climate data is determined from trial site location and national weather sources.

Rand NSW


Some data on this site is sourced from the Bureau of Meteorology

SILO weather estimates sourced from
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.

Trial last modified: 23-09-2019 17:19pm AEST