Powys farmer Jonathan Harrington explains his reasons for planting GM crops.
A farmer claims to have defied a Welsh Assembly Government vote to keep Wales free from genetically modified crops.
Jonathan Harrington, of Pen-y-Lan Farm, Tregoyd, near Hay-on-Wye, Powys, said he grew two varieties of GM maize there and gave seeds to two other farmers.
He denied breaking any laws, but anti-GM campaigners said he had for failing to register with the authorities.
The Welsh Assembly Government said it could not legally ban GM crops, but had a restrictive GM crop policy.
Mr Harrington, aged 53, told BBC Radio 4's Today programme there were "enormous potential advantages" to Welsh farmers if they decided to grow GM maize as feed for livestock.
"Unless some farmers show an interest in it, none of the plant breeders are going to to bother to develop crops for UK conditions," he said.
If the authorities want to prosecute me that's fine, I'll fight my corner
Jonathan Harrington, farmer
"I'm extremely interested in the new technology that's available through GM plant breeding ."
He questioned if he was really the first to break the voluntary ban on GM crops in Wales.
"What I've done is entirely legal. The Welsh government does not have legal responsibility for these crops," he added.
Mr Harrington chose from an EU-approved list of crops which he said was approved for growing anywhere in the EU.
He claimed as he was growing crops commercially and not as a trial, he was not required to inform the authorities of the location.
"I didn't tell anyone where I grew them because you get the anti-GM lobbyists coming around in their white suits and gloves and masks and ripping them all up," he said.
However Dr Brian John from GM Free Cymru said he believed Mr Harrington could face prosecution.
"Our reading of the regulations is that he is required to provide advance information as to where the plantings will take place, which varieties and to ensure that his neighbours are not going to be negatively affected," he said.
"I think this is a grossly irresponsible act on his part. He's making a political point here.
"He's entitled to his view and that's fair enough but to actually go ahead and plant a totally unsuitable maize variety, or two varieties, in the Brecon Beacons National Park which is a protected area is quite extraordinary.
"If he has not informed the Welsh assembly and the county council of the location, the varieties, his monitoring plan to check for contamination and to enable people to follow this material through the food chain, he has quite clearly broken the regulations and should be prosecuted."
But Mr Harrington said: "If the authorities want to prosecute me that's fine, I'll fight my corner.
"I've taken legal advice and I'm advised I've done nothing wrong."
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