| Researcher(s) |
Nicole Dimos (SPAA) Felicity Turner (Vision Ag) Grant Yates (Vision Ag) |
|---|---|
| Year(s) | 2011 |
| Contributor | Society of Precision Agriculture Australia |
| Trial location(s) |
Coonalpyn , SA
|
To compare the effects of variable rate nitrogen applications on wheat yield across varying soil types.
The trial has indicated that the application of the high rate UAN (140L/ha) over the entire paddock still proved to be a more profitable than applying the low rate over the entire paddock, however the overall gross margin benefits are not as visible due to the low yielding sand zone only occupying 9ha (13%) of the paddock. However these results confirm that the adoption of PA is an economically sound decision, indicating that the grower could make a saving of $48/ha if that extra nitrogen was not applied to the low yielding area via the use of variable rate fertiliser application. The trial results have solidly indicated that the overall gross margin would be profitably affected not having to spend the extra $62/ha on fertiliser. The gain of $53/ha in the high yield zone with high rate N (140L) is a substantial increase in profit over the low rate (60L) showing there is benefits to adding N in these zones.
| Lead research organisation |
Society of Precision Agriculture Australia |
|---|---|
| Host research organisation | N/A |
| Trial funding source | GRDC SPA000010 |
| Related program | N/A |
| Acknowledgments |
This project was funded by the Grains Research and Development Corporation (GRDC) |
| Other trial partners | AAron and Trent Long (property owners) |
| Crop type | Cereal (Grain): Wheat |
|---|---|
| Treatment type(s) |
|
| Trial type | Precision agriculture |
| Trial design | Not applicable |
| Sow rate or Target density | 80 kg/ha |
|---|---|
| Sow date | 14 May 2011 14 May 2011 |
| Harvest date | Not specified |
| Plot size | Not specified |
| Plot replication | Not specified |
| Fertiliser |
Variable rate UAN |
| # |
Treatment 1
|
Treatment 2
|
Grain yield (t/ha) |
|---|---|---|---|
| 1 | █ Low yield zone (sand) | █ UAN @ 140 L/ha | 1.62 |
| 2 | █ Low yield zone (sand) | █ UAN @ 60 L/ha | 1.56 |
| 3 | █ Low yield zone (gravel) | █ UAN @ 140 L/ha | 3.02 |
| 4 | █ Low yield zone (gravel) | █ UAN @ 60 L/ha | 2.61 |
| 5 | █ Medium yield zone | █ UAN @ 140 L/ha | 3.23 |
| 6 | █ Medium yield zone | █ UAN @ 60 L/ha | 2.98 |
| 7 | █ High yield zone | █ UAN @ 140 L/ha | 3.78 |
| 8 | █ High yield zone | █ UAN @ 60 L/ha | 3.28 |
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.
