Can agronomy overcome yield penalty of retained (F2) hybrid TT canola in the low rainfall zone?


Research organisaton
Funding source

Trial details

Researcher(s) Jackie Bucat
Bob French
Mark Seymour
Year(s) 2015
Contributor Department of Agriculture and Food WA
Trial location(s) Grass Patch, WA
Can agronomy overcome yield penalty of retained (F2) hybrid TT canola in the low rainfall zone? locations

To investigate whether agronomy can overcome the yield penalty of retained (F2) TT hybrid canola compared with purchased (F1) hybrid seed by using;

  • seed mixes.
  • increased density or,
  • grading to increase seed size.
Key messages
  • Across the trial series at Grass Patch, Ballidu, Merredin and Holt Rock the highest grain yields, oil and gross margins were from the open pollinated variety, so growers should continue to use open pollinated TT varieties in the low rainfall regions, rather than hybrid varieties.
  • In the hybrid treatments, there were generally increased yields and oil from the purchased (F1) seed, compared with the retained (F2) seed.  The gross margin was only significantly better at the Grass Patch site, for the 2014 F1 compared with the retained seed. Grading to increase seed size and sowing at a target density of 40 plants/m² improved the yield and gross margins of F2 retained hybrid seed, but at Grass Patch in 2015 using F1 hybrid seed or OP seed provided better results..
Lead research organisation Department of Agriculture and Food WA
Host research organisation N/A
Trial funding source GRDC DAW00227
Related program N/A

This trial part of the ‘Tactical Break Crop Agronomy in Western Australia’ project, which is jointly funded by the Department of Agriculture and Food Western Australia (DAFWA) and the Grains Research and Development Corporation (GRDC).

Thanks to the Sanderson family for hosting the trial and to the Esperance RSU for trial management.  Pam Burgess (DAFWA. Esperance) provided technical assistance to ensure all treatments and measurements occurred in a timely and accurate fashion.

Other trial partners Not specified
Download the trial report to view additional trial information


Crop type Oilseed: Canola
Treatment type(s)
  • Crop: Type
  • Crop: Variety
Trial type Experimental
Trial design Unknown

Grass Patch 2015

Sow rate or Target density 20 or 40 plants/m²
Sow date 24 April 2015
Harvest date Not specified
Plot size Not specified
Plot replication Not specified
Psuedoreplication Not specified

Fertiliser (kg/ha) 100 kg/ha of Agras No 1 at seeding, 117 kg/ha of Muriate of Potash) topdressed over whole site 4 weeks after seeding, 33 L/ha of UAN (32%N) June 10.

Download the trial report to view additional method/treatment information
Trial source data and summary not available
Check the trial report PDF for trial results.
Observed trial site soil information
Trial site soil testing
Not specified
Soil conditions
Trial site Soil texture
Grass Patch, WA Not specified
Derived trial site soil information
Australian Soil Classification Source: ASRIS
Trial site Soil order
Grass Patch, WA 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 Grass Patch WA
2015 522.3mm
2014 513.2mm
2013 529.0mm
2012 516.4mm
2011 509.1mm
2010 504.4mm
2009 512.1mm
2008 522.7mm
2007 510.2mm
2006 514.1mm
2005 506.8mm
2004 508.7mm
2003 533.2mm
2002 495.8mm
2001 515.7mm
2000 519.9mm
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



Grass Patch WA 2015

Observed climate information

Rainfall avg gsr (mm) 215mm

Derived climate information

Grass Patch WA

NOTE: Exact trial site locality unknown - Climate data may not be accurate

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 report and links

2015 trial report

Trial last modified: 04-09-2017 14:55pm AEST