NILE mixed farmer and canola grower Michael Chilvers has kept a close eye on Tasmania's genetically modified organism debate since the late 1990s.

Recent discussions regarding the Tasmanian moratorium on GMO again sparked his interest as talks regarding tolerance levels, seed sourcing and agricultural impacts surfaced.

Mr Chilvers was last week tending to a crop of 971CL canola destined for Japan.

It is the first time he has used the variety, which has so far proved to have a 5 to 10 per cent higher yield than his usual Australian short season type.

The crop will be harvested shortly before Christmas - it is GM-free and will gain a premium from the Asian market.

Mr Chilvers said that although he was open-minded to potential benefits from GM technology, he believed that currently the state had more to gain by remaining GM-free.

"I've been growing canola for a number of years - I'm very familiar with the issues around GM," he said.

"I don't think there's sufficient reason to change our stance with GM technology at the moment, however there's issues around what GM-free means and tolerance levels that need sorting out."

Tasmania has a zero tolerance to GMO material based on perceived marketing advantages in countries such as Japan.

In practical terms, the most sensitive test for GM canola can detect to 0.01 per cent.

Like many places in the world, Japan has a 0.9 per cent tolerance for GM - meaning any produce must fall below that rating to be considered GM-free.

Zero tolerance means Tasmanian farmers must look harder to source and test improved varieties that test negative at 0.01 per cent.

"Non-GM canola breeders work with a 0.5 per cent tolerance, and testing to 0.01 is very expensive," Mr Chilvers said.

"It is becoming a really big issue. We've been shut out of new non-GM varieties just because importing seed is so difficult.

"Tasmania uses such a small amount of seed, it's just not worth the expense to get a couple of pallets through."

Tolerance is viewed as a separate issue to the government's extended moratorium, which places strict controls on the state's GM ban.

"There may be some significant advantages to the technology. For example, in terms of insecticide use, if you look at the cotton industry the amount of insecticide used has dropped significantly with the introduction of GM cotton," Mr Chilvers said.

"If this canola, or our poppies, were RoundUp-ready, we would use a lot less chemical on these crops, but as soon as weeds develop resistance to RoundUp you're in trouble — we rely on RoundUp in other areas of the rotation. We don't want to lose it."

While the state remains hesitant to open its doors to GM technology, Mr Chilvers said it was crucial to remain engaged in the discussion.

"I think we need to be very much involved in the debate, we need to be involved in research," he said.

"If you've got concerns, you need to be in there steering it and expressing concerns - there's no point sitting on the sideline watching."