GM canola plantings at high

Rod Birch.

A record amount of genetically modified canola has been planted in WA this year.

According to figures from Monsanto, 30 per cent of WA's canola crop this season has been planted to GM varieties.

Monsanto said WA growers had purchased a record 776 tonnes of Roundup Ready canola seed, up 20 per cent on last season.

More than 337,000ha of GM canola was planted this season in WA, up from nearly 260,000ha last year.

The rise in GM canola plantings comes despite an estimated 9 per cent fall in the size of WA's overall canola crop this season.

Monsanto Australia managing director Daniel Kruithoff said WA growers had led the nation in adopting this proven technology.

"WA growers have planted more Roundup Ready canola every year since its introduction in 2010," he said.

Coorow farmer Rod Birch said he planted 100 per cent of his canola crop to GM varieties this year, up from 72 per cent of last year.

"The Roundup Ready Canola has been my highest yielding variety; there is a significant advantage," he said. "And that advantage continues to widen.

"When I first started growing RR canola in 2010, the yield advantage was about 200kg/ha.

"This has gradually increased over the years to be a 400 to 500kg/ha advantage last year, mainly because the RR varieties have improved while non-GM have stood still.

"Another important point is my Roundup Ready paddocks have been so clean for the following year's crops that I can't go backward from there."

Mr Birch said despite GM varieties trading at a discount to non-GM varieties, the yeild advantage and weed control meant the RR varieties remained the most attractive for his operation.

The current discount for GM canola is around $50/tonne, but Mr Birch said this spread often narrowed to closer to $20/tonne.

He said he did not forward trade canola when the discount was high.

Mr Birch, who received a "game- changing" 55mm rainfall on his Coorow property last week, said he expected to continue dedicating 100 per cent of his canola plantings to GM crops in coming years.

Mr Kruithoff encouraged WA growers to support the State Government's proposed repeal of the GM Crops Free Areas Act.

"The possible reintroduction of a ban on GM crops will deny WA farmers the option of using a mainstream tool they are using in greater numbers every year," he said.