Weeds found to be resistant to triazine herbicide

Another major chemical herbicide could be on its way out after resistant populations were found in Western Australia.

Two infestations of wild radish suspected of being resistant to the herbicide triazine have been discovered near Geraldton, about 400 kilometres north of Perth.

There's only been a few instances of suspected resistance to triazine previously reported in WA.

The discovery has major implications for growers of triazine tolerant, or TT, canola - a very common varietal choice for growers - and also for those growing lupins, who rely on triazine-based herbicides for post-emergent radish control.

Peter Newman, from the WA Department of Agriculture, says the genetic makeup of the resistant radish could be the key to preventing it spreading.

"The genes don't transfer in the pollen. They stay in the seed, so the main form of transfer is in the header at harvest time," he said.

"So we don't want to drive the header into these resistant populations and then drive them to another clean paddock."

Source: abc.net.au