New lucerne cultivar extends rotation options
A new grazing-tolerant dryland lucerne cultivar has been performing well in on-farm trials run under commercial conditions at a range of sites in southern and eastern Australia.
The new cultivar, SARDI-Grazer, is regarded as a valuable development for cereal growers who could benefit in terms of managing groundwater recharge, herbicide resistant grasses and cereal diseases, as well as improved nitrogen fixation and soil structure.
SARDI-Grazer is a winter-active lucerne (class 6), which was developed with GRDC funding by the South Australian Research and Development Institute (SARDI) and the Department of Agriculture and Food, Western Australia (DAFWA) over a nine-year period.
SARDI lucerne breeding program leader Alan Humphries says the new variety allows growers who lack fencing and water point infrastructure to grow lucerne in their farming systems.
“This is particularly relevant to cereal growers with large paddocks where it may take about 35 days to graze down a 50-hectare paddock. In large paddocks, grazing pressure is seldom even, and SARDI-Grazer will handle overgrazing better than our traditional lucerne varieties,” he says.
Bred to withstand persistent grazing for up to two months, Mr Humphries says SARDI-Grazer offers a persistent and productive option for mixed farms across Australia.
He says it has shown a high level of grazing tolerance on soils ranging from deep sands to clay in low, medium and high-rainfall zones.
“Plant breeding and evaluation trials leading to the development of SARDI-Grazer occurred mainly in low to medium-rainfall areas such as SA’s Murray Mallee, as well as the cereal belt in WA, so we have been pleasantly surprised to see it performing so well in high-rainfall areas such as Timboon in south-west Victoria,” Mr Humphries says.
Post-development, SARDI-Grazer has been evaluated at 26 sites in SA, Victoria, New South Wales and Queensland.
Mr Humphries says these evaluations show the cultivar is suited to a range of farming systems.
It has also shown good levels of resistance to aphids and diseases, and is expected to be drought tolerant.
Mr Humphries says SARDI-Grazer is the first major trait improvement in winter-active dryland lucerne since the Hunterfield variety was released in 1994.
The development of a grazing-tolerant lucerne variety was funded by the GRDC in response to the emerging national problem of dryland salinity and the large number of studies advocating the use of lucerne to prevent recharge and mitigate the spread of salinity.
As well as improving soil structure and being a nutritious fodder source for livestock, lucerne provides the rotational benefits of a disease break for cereals, plus nitrogen fixing.
Mr Humphries says that once established, SARDI-Grazer could be grazed in a two-paddock rotation with six to eight weeks of grazing followed by six to eight weeks of recovery: “The recovery period is critical for recharging the energy reserves of the plant so it maintains excellent levels of production and persistence,” he says.
More information:Alan Humphries,
08 8303 9651
GRDC Project Code DAS00081, DAS00347, DAS00282