Double Break Rotation Project
Increasing the profitability of the double break rotation in the MRZ of WA Wheatbelt through incorporation of an early sown high value pulse
- The combination of canola followed by a high-value legume in a double break crop sequence for the Medium Rainfall Zone can increase break crop profitability.
- The yield of cereal crops is greater within a double-break crop rotation sequence.
- Chickpeas sown early may provide greater benefits in a double break rotation over a later sowing time.
The Double Break project was conducted over 3 growing seasons, from 2020 to 2022 to evaluate the effectiveness and profitability of a double-break crop sequence. The project assessed the value of growing canola followed by a high-value legume, and the impact this rotation had on the grain yield and profitability of a cereal crop following the double break crop sequence. The contribution of an early sowing date versus a traditional sowing date to increase the profitability of these crops was also evaluated.
Following a canola crop in 2020, a farm-scale demonstration trial was established in 2021 which had Captain Chickpea sown at 2 different times, an early sowing time in mid-April and a late sowing time in mid-May. There were three treatment plots, 25m wide x 120m long divided into three equal quadrants. Treatments include 1 x wheat crop as a control, an early sown chickpea, and a late sown chickpea, with three replicates within each treatment plot. In 2021 there was no significant difference in grain yield between the two times of sowing, but early-sown chickpeas had significantly greater biomass.
In 2022, all plots were sown over with a barley cereal crop in May. Early indications show that barley sown into early sown chickpea plots, from the previous year, outperformed both the control and the late sown plots. A full project report, including an economic analysis, will be published in the 2022 Trials Book. To receive a copy and other exclusive member benefits please support us by becoming a member. Click HERE for more information.
Break crops are widely acknowledged as being necessary to manage the biological constraints such as disease, pests and weeds that reduce cereal crop yield. While break crops have traditionally been used as a single crop in rotation, the use of two consecutive break crops has been shown to greatly increase cereal crop yield and profitability.
One of the constraints in the use of a single or double break crop sequence is that the Gross Margin of the most commonly used break crops, such as canola and lupins, are generally less than growing a cereal crop. The short-term decrease in economic return from growing a break crop is offset by the longer-term benefits of decreased production costs and increased productivity of cereal crops for many years following.
The integration of high-value legumes such as chickpeas or lentils has been successful in medium to low-rainfall environments of Eastern Australia to improve crop rotation profitability while maintaining effective weed control. Recent studies in WA found that profitable grain yields of both chickpeas and lentils are achievable in the medium rainfall zone (MRZ) of the WA Wheatbelt. The impact of earlier sowing of these pulses has also been demonstrated to significantly increase the profitability of these high-value legumes. Incorporating one of these high-value legumes into a double break rotation could be a key tool to increase the productivity of following cereal crops.
Project start date: 20th April 2020
Project End date: 30th March 2023
Project Funding: Grains Research and Development Corporation
Project Lead: West Midlands Group
Project Collaborators: Liebe Group, Corrigin Farm Improvement Group
Host Farmers: Kim and Roz Sands