Achievable yields for irrigated grains in the northern region
- Researcher's Name:
- Mr Allan Peake
- CSIRO Ecosystem Sciences
- 07 4688 1137
- 07 4688 1193
- Project Code:
- Contract Start:
- Contract End:
Recent high grain prices have led to increased grain production in irrigation areas normally sown to cotton. Farmers are adapting to grains production and are inquiring about the best agronomic practices to use. This project aims to establish improved agronomic practices, and publish achievable yield and water use benchmarks, for irrigated wheat and sorghum production specific to each irrigated valley in the northern region. Specific project outputs will be published regionally-specific agronomic recommendations on how best to maximise yield for irrigated wheat and sorghum production, along with published yield and water use benchmarks. Project outcomes will be improved knowledge of irrigated grains production potential for irrigation enterprises, and improved industry understanding of the best agronomic practices to use on individual farms.
The northern grains region has recently experienced a prolonged drought and water crisis, and irrigators have experienced severe restrictions to production due to water shortages, highlighting the need for irrigators to increase the efficiency of use of irrigation water. At the same time, increased demand for food worldwide has led to recent price spikes in the Australian grains industry, and irrigation farms throughout the northern region have diversified into grain production on a scale not seen in some localities for more than 20 years. Consequently, growers and advisors are urgently seeking agronomic advice on how best to produce irrigated wheat and summer grains.
With water very much the limiting factor for irrigated farming enterprises in recent seasons, much interest also exists in understanding the amount of water required to grow different crops, and the best way to distribute limited water across a farm to maximise gross margins. Should the full cropping area receive a small allocation of water, or is it more profitable to concentrate the remaining water on a small area that will be fully irrigated?
The lack of experience in irrigated grains production in irrigation districts means that growers and agronomists are asking questions on what yield they should be targeting from irrigated grain paddocks. Irrigated wheat competitions in the region have been won with yields of 5 - 5.5t/ha, no better than good yields seen on dryland paddocks, raising the question of whether growers are already managing their crops to achieve maximum yields, or whether irrigated wheat production across the region is substantially underachieving.
This project therefore aims to assist northern region irrigators by producing yield and water use benchmarks for irrigated wheat and sorghum production across the northern region, so that the potential yield and water use requirements of these crops can be understood. The project will also provide improved agronomic recommendations for irrigated wheat and sorghum production.
The project outputs will be generated from the results of paddock monitoring, research station experiments, and a computer program called APSIM (the Agricultural Production Systems Simulator). Paddock monitoring and experiments will be used to test different agronomic strategies for achieving high yields under irrigation. These same experiments will be used to check that the APSIM can accurately simulate yield and water use across the northern region for wheat and sorghum. After making any necessary adjustments, APSIM will then be used to generate the yield and water use benchmarks for representative regions, soil types and sowing dates.
Improved agronomic recommendations, plus the yield and water use benchmarks will be presented at GRDC updates and other industry communication events. These presentations will also be prepared as written papers, published in GRDC update booklets as well as on the GRDC website. Paddock monitoring will also give growers and agronomists first-hand experience in using different agronomic techniques.
Growers and advisors will be more knowledgeable on the potential yield of wheat and sorghum under irrigated conditions, and the amount of water required to achieve these yields. By understanding the production potential of irrigated grains in their region, growers and advisors will be better able to identify underperforming paddocks, and can then improve production by investigating and addressing the production constraints. The project will also provide improved agronomic techniques to help growers achieve benchmark yields more reliably in the seasons they decide to grow irrigated grains. The benefits will be realised locally and regionally through more reliable and water-efficient grain production on irrigated farms.
Pathway to Adoption
The project outputs are (1) Improved agronomic recommendations published for irrigated wheat and sorghum production across the northern grains region, and (2) Achievable benchmark grain yield and water use requirements published for irrigated wheat and sorghum production across a range of agronomic practices relevant to the northern region. Outputs will be presented at GRDC summer and winter crop updates, published in the Update booklets and on the GRDC website
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