- RR hybrid canola maximised gross margins
- OP TT variety Sturt produced similar gross margins to the hybrid TT variety Hyola 450 TT
- Gross margins were optimised at:
- ~50 plants/m2 for Sturt TT
- ~5-25 plants/m2 for Hyola 450TT
- ~13 plants/m2 for Pioneer 43Y23 RR
To investigate the plant density response to yield and oil content of TT and RR hybrid canola in comparison with open-pollinated canola.
|Property||Tim, Dave and Fiona Osborne’s, Eldred Road Salmon Gums|
|Agzone 5, Growing Season rainfall (GSR, April to October)||175mm, GSR + stored water (estimate) = 198mm|
|Soil type||Sandy loam (0.7% organic carbon), estimated to be 58kg N/ha available in paddock from soil and plant residues|
|Paddock rotation||2013 - barley. 2012 - wheat, 2011 - wheat, 2010 - field pea|
|Sowing date||6 May|
|Fertiliser||400kg/ha of gypsum (17% Ca, 14% S) top-dressed over whole site before sowing (kg/ha),107kg/ha of Impact treated Agras No.1 at seeding, 100L UAN/ha on 19 June, 1L Mantrac/ha on 9 July and 120kg/ha of muriate of potash top-dressed over whole site 10 July|
|28 treatments|| |
Four varieties x eight target densities
Two HT - Herbicide tolerant canola (TT and RR)
TT– OP = Sturt TT and Hybrid = Hyola 450TT
RR - OP = GT Viper (data not shown due to low field establishment), Hybrid = Pioneer 43Y23 RR
Eight target densities of 5, 10, 15, 20, 30, 40, 60, or 80plants/m2. Seed rates were adjusted for germination, seed size and estimated field establishment- which varied with target density and seed type
Assumptions used in gross margins
Oil bonus: +/- 1.5% per unit of oil (%) either side of 42%, with no oil ceiling.
Additional costs such as seeding, harvest, insecticides assumed to be $100/ha.
Nitrogen costs: $1/kg, application costs $8/ha.
RR costs: OP seed $25/kg, hybrid seed $33/kg, herbicides $28/ha, grain worth $513/t (Decile 5 price).
TT costs: OP seed $3/kg, hybrid seed $24/ha, herbicides $46/ha, grain worth $535.
The OP TT variety Sturt responded to plant densities above 50 plants/m2, Hyola 450TT seed yield responded up to 25 plants/m2 while gross margins were similar at 5-25 plants/m2. Pioneer 43Y23 RR had approximately 20% higher establishment than we anticipated and its yield and gross margin plateaued at approximately 13 plants/m2.
RR hybrid canola maximised gross margins, whilst there was no difference between OP or hybrid TT canola.
|Variety and target density||Established plants per m2||GY||GM|
|Sturt TT 5||3||446||-70|
|Sturt TT 10||7||552||-14|
|Sturt TT 15||8||744||89|
|Sturt TT 20||14||765||103|
|Sturt TT 30||19||794||115|
|Sturt TT 40||38||802||114|
|Sturt TT 60||46||818||126|
|Sturt TT 80||64||911||165|
|Hyola 450 TT 5||5||772||114|
|Hyola 450 TT 10||9||780||111|
|Hyola 450 TT 15||16||813||120|
|Hyola 450 TT 20||25||895||158|
|Hyola 450 TT 30||30||797||87|
|Hyola 450 TT 40||49||972||141|
|Hyola 450 TT 60||72||819||14|
|Hyola 450 TT 80||84||864||-8|
|Pioneer 43Y23 RR 5||7||735||121|
|Pioneer 43Y23 RR 10||13||898||200|
|Pioneer 43Y23 RR 15||16||949||218|
|Pioneer 43Y23 RR 20||26||981||222|
|Pioneer 43Y23 RR 30||36||958||194|
|Pioneer 43Y23 RR 40||67||976||137|
|Pioneer 43Y23 RR 60||93||931||48|
|Pioneer 43Y23 RR 80||123||1003||21|
The results from this trial confirmed the results from previous years, with OP TT canola responding to higher plant densities than other canola due to a combination of the biological response and the low cost of increasing OP TT density. Similarly RR hybrid canola showed a flat response to plant density and consequently a relatively low plant density maximised returns. Hybrid canola responded somewhere in-between, with yields responding to higher densities than RR hybrid canola. Hybrid TT did not produce higher gross margins than OP TT, therefore the low risk option in low rainfall areas remains OP TT, with RR hybrids being the best option if weeds develop resistance to triazine herbicides.
This trial (14ED10) is one of a series conducted throughout WA as part of the GRDC/DPIRD co-funded project Tactical Break Crop Agronomy in Western Australia. Thanks to the Osborne family for hosting the trial and to the Esperance RSU for trial management. Pam Burgess (DPIRD Esperance) provided technical assistance to ensure all treatments and measurements occurred in a timely and accurate fashion.