New GRDC supported research in Western Australia showed a mix of old and new techniques can help slow the development of herbicide resistance in ryegrass, one of the most difficult weed issues growers face.

Albany based Department of Agriculture and Food researcher Dr Sally Peltzer said growers doubled cereal yields after trialling the new method that involved catching and disposing of ryegrass seed at harvest.

"Exploiting the fact ryegrass seeds hang on the stems for longer than many grasses, scientists found more than 75 per cent could be caught at harvest and added to the harvester chaff, then left in the windrow and disposed of by burial," Dr Peltzer said.

She told the GRDC supported Australian Weeds Conference in Adelaide that using a conventional mouldboard plough was the best disposal method, as seeds buried below 15cm could not emerge.