The genetically-modified tobacco plant has a gene that triggers a red plant pigment found in tomatoes and apples.

When the roots detect nitrogen oxide which leaks from landmines, the green leaves turn red about ten weeks.

Researcher Estelle Kempen, of Stellenbosch University, South Africa, said: 'It will be obvious if an area has mines because these plants will be red.

'The plants will also be able to tell if an area has been successfully cleared.

'They use this big mechanical de-mining equipment but they don't pick them all up.'

The plants have already been successfully tested in laboratories and greenhouses and are now undergoing field trials in Serbia and South Africa.

Biotechnology firm Aresa, which is carrying out the tests, had previously trialled its 'RedDetect' technology in a common weed called Thales cress, but scientists said it was too small to be seen from a distance.

The tobacco plants has been chosen because it is hardy, easy to grow and has wider leaves.

UN and landmine clearance groups are watching the tests with interest.

Aresa chief executive Steen Thaarup said: 'This could be an efficient and economic way of clearing mines.

'There is irony in using tobacco for this - it could end up saving lives for once.'

Becky Maynard at the No More Landmines charity in London, which raises funds to clear mines, said the plants would be a useful tool but communities would still rely on engineers to physically remove them.

There an estimated 80million landmines buried worldwide, covering 120,000 square miles.

Eighty four countries are plagued by them, with third world countries such as Angola, Afghanistan, Bosnia and Mozambique the worst affected.

Landmines kill or injure 18,000 people a year, with 80 per cent of victims being civilians.

Via Dailymail