Plastic crops may line farmers pockets

It sounds like the stuff of science fiction but "growing" plastic could one day be a lucrative enterprise for farmers.

In the next few decades, scientists believe advances in technology could see plant oils replace petroleum as the precursor for plastics.

More than 200 leading researchers have gathered for a biennial international conference in Cairns to share knowledge to aid the pursuit of that goal.

If and when that's achieved, the windfall could be significant for Australia's agriculture industry.

CSIRO plant industry deputy chief Allan Green says growers would be able to attract higher prices by selling their crops to plastic manufacturers.

"Some of the industrial oil targets we are looking at, they are probably 50 per cent higher than their value as food oils currently," he told AAP.

"That translates straight to the bottom line of the farmer because it's all the same growing costs."

He estimated the total size of the industry would be in the hundreds of billions of dollars.

He said that to avoid competition with the food sector, researchers were working with a crop not often utilised for food oil - Safflower.

Dr Green said trials of safflower oil polymers could begin in Australia in about five years.

Plant oil plastics would provide a greener, renewable alternative to conventional plastics, he said, and with crude oil supplies expected to dwindle in coming decades, research in the area is critical.

"We really feel a sense of urgency to get cracking on it and to foster as much collaboration as we can between the groups (of researchers)."

For plant oils to replace petroleum in plastics, the size of the industry would need to be tripled, he said.

However, he said the idea that the technology could replace crude oil as an energy source was a fantasy.

"We wouldn't like anyone to get the impression that biofuels can solve that - that will be a whole range or renewable technologies.

"We just can't make that amount of biomass."