The dual-purpose canola revolution: A game-changer for Australian farmers
The introduction of dual-purpose canola has been a game-changer for Australian farmers, adding over $1.6 billion to their returns over the past 19 years. This innovative approach to farming, developed by CSIRO and GRDC, has not only boosted profits but also improved risk management and disease control. But what makes this success story even more fascinating is the journey from concept to widespread adoption, which required extensive collaboration and a willingness to rethink traditional farming practices.
The challenge was clear: while dual-purpose wheat was already profitable in high-rainfall areas, the heavy reliance on continuous dual-purpose wheat and grass pastures led to increased disease and herbicide-resistant weeds. This prompted Dr. John Kirkegaard to explore dual-purpose canola as a forage and break crop, with the potential to reduce canola's risk in dry years through grazing or hay production.
The proof of concept came in the form of small-plot trials near Canberra, where April-sown canola planted into uncultivated seedbeds produced 2.5 to 4.0 t/ha of forage for winter grazing. This was further supported by the work of Dr. Hugh Dove, who quantified the livestock response, showing that Merino lambs grazing canola could gain 210 g/day.
However, one of the early knowledge gaps was the management of blackleg in dual-purpose canola. Researchers expected that grazing damage during winter spore release would heighten disease severity. Dr. Susie Sprague, with GRDC co-investment, joined the team to resolve this issue. Her work showed that while grazing increased blackleg severity, it could be minimized by selecting highly resistant cultivars, grazing during the vegetative stage before stem elongation, and avoiding heavy grazing.
The results of these small-plot trials were strong enough to move beyond small-plot trials. Commercial trials began at Bobbara Station, near Galong, NSW, using European winter canola varieties. These trials provided valuable insights that refined best management practices, including the suggested stocking rate of 30 dry sheep equivalents per hectare and the timing of grazing to avoid bud elongation.
The benefits of dual-purpose canola were further confirmed by whole-farm analysis, which showed that dual-purpose canola and wheat increased greasy fleece weight, weaner lamb sale weight, and meat production per hectare. Grazing reduced canola yields by 17% on average, but this reduction was small when viewed across the entire enterprise.
The impact of dual-purpose canola has been recognized with the CSIRO Sir Ian McLennan Impact from Science and Engineering Medal in 2021. The award acknowledged the contribution of dual-purpose canola to productivity, sustainability, and mixed-farming resilience, supported by long-term GRDC investment.
Today, research continues through co-investments by GRDC, CSIRO, and the NSW Department of Primary Industries and Regional Development in farming systems projects. The goal is to refine the role of dual-purpose canola so that its high water and nitrogen use do not reduce whole-farm profitability.
In conclusion, the introduction of dual-purpose canola has been a game-changer for Australian farmers, adding over $1.6 billion to their returns and improving risk management and disease control. The journey from concept to widespread adoption required extensive collaboration and a willingness to rethink traditional farming practices, but the results have been well worth the effort.
