Irrigated grain growers will have access to a new suite of knowledge regarding agronomy, soils and economics of irrigation thanks to a range of GRDC investments that have recently been contracted.

Three linked investments will cover a range of issues facing irrigators. They are:

• 'Development and validation of soil amelioration and agronomic practices to realise the genetic potential of grain crops grown under a high yield potential, irrigated environment in the northern and southern regions', led by FAR Australia;
• 'Optimising farm scale returns from irrigated grains: maximising dollar return per megalitre of water,' led by the University of Tasmania; and
• 'Facilitated action learning groups to support profitable irrigated farming systems in the northern and southern regions', led by the Irrigated Cropping Council (ICC).

The FAR Australia investment is due to begin in Spring 2019, with the aim of developing and evaluating the effectiveness of novel soil management technologies and crop-specific agronomic management practices on farming system profitability.

FAR Australia managing director Nick Poole says the crop-specific agronomic practices will focus on maximising system profitability through three different areas.

"We will be looking at establishing updates to benchmarks for the productivity of key crops under different irrigation systems," he says.

"In order to achieve this we will be looking at optimising the return on nitrogen through improved use efficiency, as well as improving the understanding of nitrogen form, timing and rate in the context of irrigation timing and interrelated agronomic decisions.

"We will also look to gain more understanding on how to consistently optimise yield in the context of water price, input costs and commodity price for the crops where gaps are most apparent."

According to GRDC, about 400,000 hectares of poorly structured grey sodic clay soils and 750,000ha of shallow transitional red brown earths exist under irrigation in the southern Murray Darling Basin.

These soils are prone to dispersion, poor water infiltration, waterlogging, impared root growth and low natural fertility. In a recent study, only 30 per cent of monitored wheat crops achieved more than 80 per cent of their water limited yield potential, with waterlogging and poorly timed irrigation some of the key factors contributing to the yield gap.

Mr Poole says the soil management technologies investigated as part of the investment will focus on improving soil structure, infiltration and moisture retention on shallow and poorly structured red duplex soils and sodic grey clays prone to dispersion and waterlogging.

Research will focus on six crops:

• faba beans
• chickpeas
• durum
• canola
• maize
• barley.

The principal research centres at Kerang, in Victoria, and Finley, in NSW, will cover all four autumn-sown crops with the addition of spring-sown maize at other locations in the Murray/Murrumbidgee region.

Satellite centres will be established at Frances, in South Australia, Griffith, in NSW, and in Tasmania with a smaller number of trials per annum.

The soil amelioration research - to be conducted in collaboration with NSW Department of Primary Industries - is based on two large block research trials at Kerang (grey clay soils under floor irrigation) and Finley (red duplex soils under overhead irrigation).

New technology

The main outcome from the University of Tasmania investment will be the development of a freely available web and phone appl that will help growers and consultants identify optimal water allocations for a range of irrigated crops across their farm.

Senior research fellow at the Tasmanian Institute of Agriculture Dr Matthew Harrison says the tool will allow users to determine the optimal combination of crops and irrigation to maximise farm profits.

"The Irrigation Optimiser was previously developed by the University of Queensland's Queensland Alliance for Agriculture and Food Innovation under the National Program for Sustainable Irrigation project with a focus on cotton," he says.

"However, over the years the software platform has become obsolete. GRDC has recognised the value of the tool and invested in an upgrade of the tool, increasing its functionality for a greater number of irrigation grain growers."

Dr Harrison says some typical questions the tool will inform include:

• Given a limited availability of land and water for irrigation and current water and crop prices, what crop should be irrigated, how much water should be applied, and on what area of land to maximise profits? How can this be applied over the whole farm, accounting for variation in crop types and irrigation infrastructure across and between paddocks?
• How does the type of irrigation system - overhead laterals, pivots, flood irrigation - affect crop gross margins and whole-farm profitability?
• What is the risk or likelihood that the projected outcome will occur?

Learning groups

The ICC has partnered with:

• the MacKillop Farm Management Group
• Southern Farming Systems
• Riverine Plains Inc
• Southern Growers
• the Maize Association of Australia
• the Irrigation Research and Extension Committee.

Small groups - called irrigation discussion groups - will be formed, enabling growes to become actively involved in the research process.

ICC executive officer Dr Charlotte Aves says the vision for the groups is to increase the profitability of irrigated cropping by supporting growers to try research methods or ideas that spark their interest.

"Using the small discussion group approach, we will create an environment where growers can learn from each other," she says.

"These action learning groups will discuss research results from the other investments relevant to their region and local farms.

"They will also support other growers in helping to manage the risk of implementing change within their business."

The groups will meet four times a year and will discuss treatments they would like to see in the agronomy and soil trials.

They will also investigate how they can contribute to the development of the economics tool, help to design and implement focus paddock projects and be involved in comparitive analysis of research, focus paddocks and standard practice to determine where the best return on investment lies.

More information: Nick Poole, 03 5265 1290, nick.poole@faraustralia.com.au; Dr Matthew Harrison, 0437 655 139, matthew.harrison@utas.edu.au; Dr Charlotte Aves, 0416 400 979, charlie.aves@irrigatedcroppingcouncil.com.au