COOL climate cropping has taken off in southern Australia in recent years.

Now researchers suggest yields could be boosted by at least 20 per cent.

Penny Riffkin, an agronomist with the Department of Primary Industries in Victoria is working with a team of scientists to boost wheat and canola yields in high-rainfall areas.

"We have used crop simulation models to help growers identify which options are most likely to give greater yields and returns," Penny said.

Strategies included time of sowing, nitrogen fertiliser, stubble management, opportunity cropping, irrigation and grazing of crops.

Data was collected from farms at Meredith, Dunkeld and Mininera in Victoria, Launceston and Campbell Town in Tasmania and Frances and Millicent in South Australia.

The information has been used to develop fact sheets showing the impacts of management on crop yields. The sheets are available from the Southern Farming Systems and Mackillop Farm Management Group websites.

Penny is also working with a UK wheat physiologist to develop a wheat crop that is best able to capture rainfall and sunlight and minimise exposure to frost, heat and drought.

She is also conducting research into winter canola types from Europe.

"We have tested some European germplasm at Hamilton and are finding it is out-yielding existing crops by up to 20 per cent, even though Hamilton has recently been through some tough, dry seasons," Penny said.

Ten cultivars are under evaluation at four locations in southwest Victoria.

"We need to identify crops and management practices that can consistently give growers higher yields and profits," Penny said.

Meanwhile, the CSIRO's chief plant industry scientist Dr Hugh Dove says replacing 20 per cent of a farm's pasture in the high-rainfall areas with a dual-purpose cereal could boost gross margins by $20 to $45 a hectare.

Further increases were possible by including a spring brassica crop between the pasture and cereal phases.

Dr Dove said computer simulation studies over 30 years at three sites showed that whole-farm gross margins could be increased by 20 per cent by including dual-purpose cereal.

The effects of crop grazing on grain yield were small when stocking rates were 35 sheep/ha or below.

He said growers who aimed to get 1000 sheep grazing days from the crop, such as 33 sheep/ha for 30 days, were likely to have minimal impact on grain yield.

Post-grazing plant growth would be slower than in ungrazed crops so flowering may be delayed by up to two weeks and while this may avoid frosts it could shift grain ripening into hotter weather and possibly reduce grain yield.

A tip when grazing young stock was to add magnesium and sodium supplements as these were lacking in wheat forage.

Dr Dove said the simulations suggested the results may be transferable to drier climates.

Both projects are funded by the Grains Research and Development Corporation.