Ground Cover North : Ground Cover 071 November-December 2007 - North
Pastures GROUND COVER NOVEMBER -- DECEMBER 2007 18 Pasture's guardian Angel Tolerant to sulfonylurea herbicide residue, a new strand medic is destined for the cereal-livestock zone BY KELLIE PENFOLD n Researchers behind the development of a new strand medic, AngelA, say it will provide more flexibility in crop rotations because of its ability to be sown or regenerate following cereal crops to which sulfonylurea (SU) herbicides have been applied. The new medic was launched at this year’s Hart Field Day in South Australia by PlantTech. AngelA was bred by John Heap and Chris Preston at the CRC for Weed Management Systems at the University of Adelaide, and was developed by Jake Howie and Craig Bell of SARDI Pastures, with support from the GRDC. It was released through the Australian Pasture Alliance (APA), a joint venture of SARDI and Seedmark to provide pasture options to graingrowers. Conventionally bred, AngelA is a mutant derivative of the popular strand medic HeraldA and, according to Jake Howie, not only is it tolerant to the SU soil residues tested so far, but has the ability to take advantage of SU residual weed control in the pasture phase, resulting in a legume- dominant pasture with fewer weeds. SU herbicides such as triasulfuron, chlorsulfuron and metsulfuron-methyl are used extensively in the cereal-livestock zones of temperate Australia because they are cost-effective, safe to use and provide good levels of residual activity. However, in low-rainfall areas with alkaline soils, residues can persist at damaging levels for subsequent pasture legumes. “The release of AngelA means growers in these areas who are committed to using SU herbicides in their cropping phase can still grow productive annual-legume pastures with all the usual benefits, such as cereal root disease reduction, nitrogen fixation and weed control, while providing a good livestock feed,” Mr Howie says. He says there is also the potential for AngelA to become a tool in the management of branched broomrape in SA’s broomrape quarantine zone. Estimated to suit eight million hectares of Australia’s cereal-livestock zone, AngelA is said to be best suited to neutral to alkaline loamy sands, and loams that receive more than 275 millimetres of annual rainfall in southern environments and more than 175mm growing- season rainfall in northern NSW/southern Queensland. AngelA will grow well in any area currently growing HeraldA or Harbinger. Trials have been run in SA, Queensland, NSW and Victoria to compare the relative effect of SU herbicide residues applied the previous year on AngelA and HeraldA. All confirmed AngelA’s ability to tolerate SU residues from a range of typical application rates. “It will also allow growers to use certain SUs in summer weed-control programs, where typically a pasture regeneration the following autumn might have been at risk of significant damage or production loss,” Mr Howie says. Apart from its enhanced tolerance to SU herbicide residues and some other Group B herbicides, AngelA’s overall herbicide tolerance is the same as for other annual medics. The medic breeding program is developing and testing new germplasm based on interspecific hybrids of AngelA crossed with barrel and disc medics that, if successful, will extend the range of adaptation. A new project has also started, with the assistance of voluntary grower levies via the South Australian Grains Industry Trust, in which the tolerance of AngelA is being tested to the simulated residues of new or previously untested SU herbicides, and to other Group B herbicides applied post-emergent for weed control in the pasture phase. GRDC Research Codes DAS00003, JRF46 More information: PlantTech, 1800 112 400, www.planttech.com.au Hart Field Day feature: Page 31 Fast and ... faster - up to 100 litres a minute For your nearest reseller call: 1800 185 102 email: email@example.com ® GP rapid-flo is a registered business name of Macnaught Pty Ltd. GP rapid-flo® Macnaught GP rapid-flo® hand-operated fuel pumps deliver high volume fuel transfer, easy operation and superior quality in a durable long life assembly. These no nonsense Australian designed bi-directional pumps will move up to 100 litres of diesel, petrol, avgas, kero and >SAE30 lubricating oils per minute. www.macnaught.com.au This pump goes with these. . . DM150 flow meter + filter - accurately measures fuel output and removes line impurities. DG connector kit • • IMC MAC 8637-GC2 The newly released AngelA medic growing at the Hart trial site in South Australia.
Ground Cover 070 September-October 2007 - North
Ground Cover 072 January-February 2008 - North