Sowing retained Hybrid TT canola not worth the risk
Canola growers in low rainfall areas considering using retained hybrid Triazine Tolerant (TT) canola seed would be better off growing open pollinated canola varieties.
Research by Bob French of the Department of Agriculture and Food showed a significant yield loss from using retained (F2) hybrid TT seed compared with purchased (F1) hybrid TT seed.
The research compared the performance of F1 and F2 Hyola 450 TT seed at low rainfall sites at Ballidu, Merredin, Holt Rock, Cunderdin and Grass Patch, as well as the open pollinated (OP) variety ATR Bonito.
The results showed an overall yield loss of 17% as well as a 1% decrease in oil content from the retained F2 seed compared with the purchased F1 seed, resulting in a $76/ha reduction in gross margin.
However, the OP variety ATR Bonito out-performed both the F1 and F2 hybrid crops.
When sown at 40 plants/m2, the OP variety generated a 210kg/ha yield increase and $150/ha more than the F1 hybrid TT variety, in addition to a 1% oil content improvement.
Development officer Jackie Bucat said agronomic strategies to boost the performance of the F2 seed were tested and while they did improve the yields of the retained (F2) hybrid, they did not match the purchased (F1) hybrid, or the OP canola.
Increasing plant density had a significant impact on F2 crops.
The strongest F2 results were produced from doubling the plant density to 40 plants per square metre, which improved the F2 yield by an average of 105kg/ha, an improvement but still 85kg/ha less than the F1 planting at the lower plant density.
Grading the F2 seed also produced a small yield improvement, however, the F1 seed still yielded better.
Various mixes of F1 purchased seed and F2 retained seed were tested but the yield and oil content results were directly proportional to the amount of seed in the mix; the higher the F1 seed the better the result.
When only F2 retained seed was used, the yield was 904kg/ha, while a mix of half F1 and half F2 yielded 1051kg/ha, and 100% F1 seed yielded 1094kg/ha.
The research highlighted the yield risk of using retained, low cost F2 seed and reinforced the superior performance of OP varieties in the low rainfall area.
It is not worth retaining TT hybrid seed, especially when compared to the better yield and gross margin of OP canola.
Farmers are encouraged to pay any end point royalties (EPRs) due on OP canola, to support the development and release of new lines that are tailored to the Western Australian grains production environment.
The department anticipates undertaking further trials this season as part of the GRDC’s Tactical Break Crop Agronomy in Western Australia project.
This project is co-funded by DAFWA and GRDC.
For further information refer to the 2016 GRDC Research Updates paper Open pollinated canola is the better option.
For more information contact Bob French, Research Officer, Merredin on +61 (0)8 9081 3126 or Jackie Bucat, Development Officer, South Perth on +61 (0)8 9368 3481.