Weed benefits from world first clover

14/2/07
Agriculture and Food Minister Kim Chance today released the world's first commercial variety of eastern star clover, bred by the Department of Agriculture and Food.
Mr Chance said the new variety, AGWEST? Sothis, would give WA grain growers a major advantage in controlling herbicide-resistant and other problem crop weeds.
"AGWEST? Sothis is suited to Wheatbelt regions with 325 to 450mm annual rainfall and can grow successfully on mildly acid and alkaline sandy-loam and loam soils," he said.
"It germinates very late in the season, compared with traditional pasture legumes and weeds that germinate rapidly at the break of season.
"In regenerating pastures, this delayed germination offers farmers an important opportunity to use non-selective herbicides and intensive grazing to control weeds during the pasture phase without a major impact on pasture growth."
The department's research indicates non-selective herbicides can be used for three to six weeks after the season break, to reduce weed density by more than 90 per cent.
The density of AGWEST? Sothis was only moderately reduced by a knockdown herbicide treatment compared to subterranean clover (35 per cent reduction, compared with 97 per cent).
The Minister said AGWEST? Sothis eastern star clover was collected on Greece's Naxos Island in 1995.
Intensive hard seed studies by the department led to the discovery of its delayed germination and the potential benefits of the species to allow for better control of herbicide-resistant weeds in current and emerging farming systems.
"The ability to control weeds early in the growing season is critical for successful pasture establishment," Mr Chance said.
"Unlike other current pasture legumes, late sowing of AGWEST? Sothis does not appear to significantly reduce its yield.
This innovation in pasture plant improvement can make a substantial contribution towards addressing one of the major threats to our agricultural systems."
AGWEST? Sothis can grow rapidly in late winter/spring and produce a productive legume-dominant pasture for grazing or forage conservation.
It is an erect, hard seeded variety with early to mid maturity. Its upright habit makes it an ideal plant for mixtures with grasses that can be used later in the season for conserving silage or hay.
It was developed and field-tested within the National Annual Pasture Legume Improvement Program supported by the Grains Research and Development Corporation, Australian Wool Innovation and the Centre for Legumes in Mediterranean Agriculture.
Seed will be commercially available in 2008 from seed licencees Ballard Seeds and Seed Distributors; and the Pasture Producers Association.
Minister's office - 9213 6700