High rainfall cropping

The high rainfall zone is a new and expanding environment for cropping, but studies indicate that crops in this zone are performing well below potential based on available sunlight, water and temperature.

Historical information from Australia and overseas, together with some of the newest breeding material from the UK and Europe is being used to find answers to improve profitability and adaptation of high rainfall croppers.

The crop design tool is using historical climate and established physiological principles from high and lower rainfall cropping zones in Australia and overseas to identify crop characteristics suited specifically to the high rainfall zone of southern Australia and fast track breeding programs.

Not only does it have potential to design crops for new environments such as the high rainfall zones but also for changing environments as may occur under climate change.

High rainfall zone cropping video

Dr Penny Riffkin, Senior Research Agronomist

Drier years and new technology has seen major expansion of cropping in higher rainfall areas of Victoria, but research suggests results could be 25 to 50% better.

Department of Primary Industries scientists are combining history and the latest breeding material from around the world to unlock the secrets to growing crops in high rainfall areas.

Cropping in the high rainfall zone is increasing due to drier climates and climate change. However, the yields that we're achieving in the high rainfall zone are still well below what we believe is the potential.

The Department of Primary Industries is investing in cropping research in this area so that returns to growers may be improved and also the future food demands can be met.

The high rainfall area is quite different from traditional cropping areas in the rest of Australia.

We have a much longer growing season and this provides a lot more options for growers. They are able to sow in autumn or in spring — they have the option of grazing crops, so this provides a lot more complexity for making management decisions.

Also, because this is a relatively new area we don't have the germ plasm or the type of cultivars which are well adapted to this area.

So we believe we can get quite significant gains by identifying what germ plasm might be better suited to this area.

We're not starting from the ground when we're looking at improving crops in the high rainfall zone.

Although this is a new cropping area, there is a lot known from research in other regions, hundreds of years of breeding and management, and we believe we can use this and we can apply this knowledge to increasing the yields in the high rainfall zone.

We've developed a crop design tool, which is designed to identify the environment in the high rainfall zone, what sort of resources we have in the high rainfall zone, how much rain, how much radiation that the crop can be used to produce grain and then looking at how to distribute that dry matter that's produced by the crops to make the most efficient crop that we can, as well as avoiding all the other risks that might be in the high rainfall zone, such as frost.

We are using crop models and historical climate data, along with site-specific information, particularly specific to the high rainfall zone that we can look at the probability of growers achieving certain yields under different management practices.

We're also looking at taking technology from overseas. We're looking at some new canola varieties that are grown specifically in Europe — they're not commercially available in Australia.

We've done some testing of those in the high rainfall zone already and we're finding that these are having around about a 20% yield increase. So we're looking at further testing those over a wider area, looking at more cultivars to see if we can get significant gains through the importation of new varieties, but also by trying to identify what characteristics it is in those varieties that may actually make a better adapted cultivar for this environment.

Impacts of management on crop yields and profit

This work uses existing simulation models, 120 years of historical climate data and detailed site specific information to look at the probability of achieving an outcome from different management options.

Growers from Victoria, Tasmania and South Australia identified management options including:

  • time of sowing
  • N fertiliser
  • stubble management
  • opportunity cropping
  • irrigation
  • grazing of crops

Data was collected for 2 years from on-farm case-study sites in these states and then applied to a model to produce information for a series of fact sheets which are now available on Southern Farming System.

Canola breeding

Researchers are sourcing and assessing germplasm from other high rainfall regions from Australia, the UK and Europe for potential use in Victoria in the future.

For more information call the Customer Service Centre on 136 186.

Page last updated: 28 Mar 2022