Plant turns red to detect landmines

Aresa Biodetection, a Danish Company, has genetically modified the plant species arabidopsis thaliana (Thale or mouse cress) so that it turns red in the presence of old landmines.

The technology takes advantage of genes that cause plants to turn red in autumn. The modification causes plants to respond to different stimulous, in this case, the nitrogen dioxide or heavy metals that are released into soil as landmines decay.

“Such stimuli trigger the production of a key-enzyme in the biochemical pathway responsible for production of the group of red pigments called anthocyanins. The resulting colour change is expected within 3-6 weeks dependent on the growth conditions.”

Old landmines kill nearly 26,000 people in third world countries every year, where vast areas of farmland cannot be safely worked because of uncleared ordinance (90% of Angola and 40% of Cambodia, for example). The technology has excited a lot of interest, but is not without skeptics.

“Unfortunately Aresa didn’t take into account something known as ‘nitrophiles’ which are widespread nitrogen fixing bacteria that release NO2 as a by-product and therefore could also trigger the plant to change colors causing enormous amount of effort and strain to dig up mines that are non-existent. I think it’s a great idea, but I am against planting non-native plants that could overtake natives and genetically modified plants that could affect the genetic community at large.”

To counter fears that the genetically-modified plants might spread naturally into the environment, Aresa claims that male-sterility can be introduced into plants, to control growth.

“Thus, the plants developed by Aresa neither germinate nor set seeds unless a specific growth hormone is added to the plants, so plant growth can be strictly controlled.”

The company reports that the technology is now in the last stage of the patent process, and work on the plant itself is being fine tuned. They hope to start field testing in the Balkans in the spring of 2005.