Lessons from the national Hyper Yielding Crops project have led to two new initiatives to help growers boost yields and profits

With trials in five states, across four growing seasons from 2020 to 2023, the Hyper Yielding Crops (HYC) initiative has set new benchmarks for cereal yields in Australia’s high-rainfall zones (HRZ).

It has also identified key factors in leveraging better yields when water is not a limiting factor. And through 25 farm focus groups and annual HYC Awards, it supported grower adoption of hyper-yielding tactics. These awards recognised the highest-yielding commercial wheat and barley crops, and the highest yielding in terms of potential (Table 1).

Trial crops yielded up to 15.2 tonnes per hectare of wheat, 13.7t/ha of barley and 6.5t/ha of canola. Growers participating in the project produced commercial wheat crops yielding up to 13.3t/ha of wheat and 10.7t/ha of barley.

While the HYC project ended in June 2024, its success has led to two new GRDC investments. The first project, ‘Hyper Profitable Crops’, will use cereal paddock benchmarking and innovation groups to help growers implement practices that boost yields and profits.

The second project, ‘Hyper Yielding and Profitable Cereals’, extends the HYC research to assess whether the ‘yield levers’ identified in the HRZ can also boost yields in lower-rainfall areas.

Table 1: Highest-yielding commercial wheat and barley crops (t/ha) and potential yield
for wheat and barley in the Hyper Yielding Crop Awards, 2020–23.

Source: FAR Australia

HYC results

Field Applied Research (FAR) Australia led the HYC initiative, which evolved from the Tasmania-based Hyper Yielding Cereals project.

The aim was to challenge the boundaries of productivity in the high-yielding regions of southern Australia and close the yield gap between potential and realised crop yields.

Project leader Nick Poole says growers have taken a keen interest in the HYC field days and farm discussion groups, which have highlighted what is possible. He is quick to recognise the good growing conditions that prevailed during the life of the HYC project, which meant soil moisture was not a constraint.

Agronomic levers the HYC project identified to boost yields included disease management, soil fertility and variety selection.

Photothermal quotient yield targets

In these high-yielding environments, a new study has found it is solar radiation and temperature in the critical period for growth that is more likely to constrain yield than water.

The new study by CSIRO and FAR Australia highlights the importance of considering photothermal quotient (PTQ), which analyses solar radiation and temperature when targeting high yields.

The combination of cooler, sunnier conditions in the three to four weeks before flowering and 10 days after flowering has long been associated with better growth and more grains in cereals.

“PTQ provides farmers with a benchmark to assess the yield of their crops,” Mr Poole says. “If their yields are well below the benchmark, it means there is scope for improved crop management or genetics.”

In the right seasonal conditions, PTQ calculations suggest that Tasmania could challenge the world record for wheat, which is currently held in the United Kingdom at 18t/ha.

Understanding PTQ principles also underpins the success of spring-sown barley in Tasmania.

In project trials in 2023, a five-month spring-sown barley crop and an autumn-planted nine-month wheat crop both had the same yield potential, and both produced more than 13t/ha.

“The critical period for grain number development and grain fill with the spring-sown barley occurred later in the season, so it was able to take advantage of higher solar radiation during longer summer days,”  Mr Poole explains.

While HYC has focused largely on the HRZ, it also included a high-altitude site at Wallendbeen in southern NSW, not typically seen as part of the HRZ.

At an elevation of almost 500 metres, Wallendbeen also has long days of sunlight with cooler temperatures, making it a prime high-yield location, and it proved a consistently high-yielding site in HYC trials.

Kenton Porker is leading research to optimise yields in the low and medium-rainfall zones of southern Australia. Photo: Melissa Marino

Soil fertility

Contrary to expectations, HYC found that large applications of fertilisers were not necessary to achieve the highest yields.

In the project, nitrogen application rates of 150 to 200 kilograms of nitrogen per hectare were enough to optimise yields of 10t/ha or more.

“There was no consistent evidence of yield response above these fertiliser application rates,” Mr Poole says. “It’s often difficult to prove there is a yield response beyond 150kg/ha, although once yields level off, protein levels might still be going up.”

He says that longer-term soil fertility built up through effective crop rotations has proved more beneficial in providing reserves of nutrition that could be accessed by plants in high-yielding years.

In canola trials in 2021, animal manure was incorporated into soils at sowing to mimic fertility, and this increased grain yields by 0.5 to 1.2t/ha at all sites.

Disease management and new germplasm

“Disease management of susceptible varieties is one of the most important aspects to get right in terms of closing the yield gap between realised yields and potential yields,” Mr Poole says.

The HYC project showed that fungicide application in cereals is essential to generate profitable hyper-yielding cereals in susceptible varieties. However, Mr Poole cautions that the overapplication of fungicides could lead to increased pathogen resistance.

Screening germplasm suited to the HRZ for both higher yields and disease resistance was an important part of the HYC project and successfully underpinned the commercial release of new elite varieties.

Varieties commercialised through the HYC project include the winter white wheats Stockade and RGT Wauge, winter red wheats RGT Accroce and RGT Cesarioe,  red wheats Anapurna, BigRede and Longforde, and the barleys RGT Planet e , Neoe CL and Newton.

The demonstration of this germplasm under Australian conditions through the HYC project contributed to their commercial release to Australian growers, with the lines now included in the National Variety Trials.

Australian grain yield records (in trials)

Hyper profitable crop discussion groups

Growers learning from growers has been key to the success of HYC, and this strategy is being continued through the new $2.7 million investment in the Hyper Profitable Crops (HPC) project, focused on wheat and barley.

FAR Australia is also leading this project, with seven innovation and benchmarking hubs throughout the HRZ for the 2024–26 growing seasons.

The hubs will facilitate discussions and hands-on crop inspections to help growers explore and implement innovative agronomic practices to improve farm profitability.

There have also been 17 grower discussion groups established across southern Australia in conjunction with grower groups.

Grower groups involved include FarmLink Research (southern NSW), Riverine Plains (north-east Victoria, south-east NSW), Southern Farming Systems (HRZ of Victoria and Tasmania), Mackillop Farm Management Group (SA), South East Premium Wheat Growers Association (south-east WA), and Stirlings to Coast Farmers (south coast, WA).

Farm paddock benchmarking will allow growers to compare cereal agronomy, production and financial performance.  Each innovation hub will also support a small trial program.

Strong interest

Former FAR communications and events manager Rachel Hamilton says there has been strong interest in the grower discussion groups, which have particularly encouraged Gen Y growers to join.

“Growers are leading these discussion groups with the assistance of our technical expertise and the farming groups involved. But it’s about the growers essentially leading that change,” she says.

The HPC project includes the development of a high-rainfall cropping manual, which collates research and case studies to demonstrate how to best leverage rainfall in the HRZ for high-yielding and profitable crops.

Other collaborators in the HPC project include Agworld and the Centre for eResearch and Digital Innovation (CeRDI)  at Federation University Australia.

Yields in low and medium-rainfall zones

Research to boost yields is being extended through a new complementary investment in ‘Hyper Yielding and Profitable Cereals’. This will provide new insights into raising yield potential in environments where water is the limiting factor, with trial sites in South Australia and Victoria.

CSIRO Farming Systems researcher Dr Kenton Porker is leading the project, investigating tactical agronomic strategies to achieve “aspirational yield targets”. This will include developing appropriate crop checkpoints throughout the season.

“Previous research in the HRZ lifted yield expectations, which meant growers in the MRZ and LRZ were questioning what was possible in their own environments,” he says.

“Agronomic systems in the LRZ and MRZ differ from high-rainfall areas mainly due to water limitations and greater variability in supply.”

Dr Porker says trial sites in both states will help assess how tactical decisions impact yields and the economic benefits of different strategies.

Project partners

Partners in the project include the South Australian Research and Development Institute (the research arm of the  Department of Primary Industries and Regions), Frontier Farming Systems, EPAG Research,  Ag Innovation & Research Eyre Peninsula (AIR EP), Hart Field Site Group, the University of Adelaide, FAR Australia, AgCommunicators,  Ag Insights Consulting, Elders and local advisers.

GRDC sustainable cropping systems manager Dr Courtney Peirce says the two projects will support better adoption of tactical agronomy for maximising yield during critical periods in variable climates.

“GRDC’s investment in this initiative reflects our plan to propel growers and industry forward by hitting and exceeding yield and profit targets across every paddock and every season.

“It will give growers confidence to either continue to adapt or to shift from conservative low-input approaches to more ambitious strategies when conditions are favourable.

“They will also provide benchmarks to guide tactical decision-making, linking agronomy to critical periods and yield changes,” Dr Peirce says. 

More information: Rebecca Murray, rebecca.murray@faraustralia.com.au;
Kenton Porker, kenton.porker@csiro.au

Resource: Influence of photothermal quotient in the critical period on yield potential of cereals – A comparison of wheat and barley