Since January, rain records for some locations in the north east of the Western Australian wheatbelt exceeded 200mm (300mm in some places) with much of this falling in March. The bottom line was, the soil was wet and it was 1 April! Some were wondering "when do I start seeding? What if it did not rain again until June?"
Unfortunately there is limited trial data for sowing much earlier than 25 April.
The trial at Pindar was sown to:
- Compare the yield responses of six wheat varieties sown at three sowing dates (9 April, 23 April and 12 May)
- Validate phenology and yield predictions of the Yield Prophet tool with very early sowing times.
In theory, APSIM (and of course Yield Prophet) can model what will happen and quantify the risk of heat shock and/or frost. This trial will enable validation of the Yield Prophet to support growers with variety decisions and management with early sowing opportunities.
This trial is one of a trial series conducted in 2015. In addition to this trial at Pindar there is also a wheat trial at Yuna and a canola trial at Pindar.
Trial details
| Sowing dates | 9 April into moist soil 23 April into moist soil with drying top soils 12 May into moist soil with drying top soil |
|---|---|
| Fertiliser | Agras Extra 100kg/ha drilled with seed |
| Varieties sown | Forrest, Mace, Magenta, Trojan, Westonia and Yitpi |
| Targeted plant density (TPP) | 60 and 120 plants/m2 (adjusted for germination and seed size but equivalent to approximately 30 and 60kg/ha |
Results
Plant establishment
| Variety | TPP 60plants/m2 | TPP 120 plants/m2 |
|---|---|---|
| Forrest | 42 | 77 |
| Mace | 73 | 102 |
| Magenta | 33 | 80 |
| Trojan | 39 | 64 |
| Westonia | 61 | 115 |
| Yitpi | 60 | 99 |
Plant development
Varieties differ in development. They will begin flowering at different times when sown at the same time. Some varieties sown in early April are flowering in mid-late June. Other varieties have only started to bolt. Varieties sown in early May are still tillering.
| Variety | Sowing date 9 April 2015 | Sowing date 23 April 2015 | Sowing date 12 May 2015 |
|---|---|---|---|
| Forrest | Start of booting | Start of stem elongation | Mid tillering |
| mace | Flowering | Flag leaf visible | Mid tillering |
| Magenta | Early flowering | Flag leaf visible | Mid tillering |
| Trojan | Early Flowering | Flag leaf visible | Mid tillering |
| Westonia | Flowering | Ear half emerged | Mid tillering |
| Yitpi | Ear 3/4 emerged | Second node | Mid tillering |
Acknowledgements
Financial support for this trial has been provided by the Grains Research and Development Corporation's Regional Cropping Solutions Network in Western Australia. Yield Prophet reporting managed by Richard Quinlan at PlanFarm. DAFWA's research support unit for trial managment and Melaine Kupsch for data management. Appreciation of the Mullewa Dryland Farming Initiative and the Thomas family for access to trials site and field day events.