As crazy as it sounds that a plant can warn a human about explosives in the area, the science is quite simple.
Plants have roots, roots suck up water, and if there are specific explosive chemicals in the groundwater they suck up (such as the nitroaromatic compounds often used in land mines), well, we can ask the plant to let us know, or should I say, lettuce know.
It’s just a matter of inserting some “carbon nanotubes” in their leaves. These nanotubes will detect those nitroaromatic compounds, and so, when a plant sucks up groundwater containing nitroaromatic compounds, these nanotube-containing leaves will glow a certain colour to warn us.
It’s almost that simple anyway. You need a camera called a “Raspberry Pi” to shine on the leaves. It’s similar to your iPhone camera, and it’s what will detect the phosphorescent glow in the leaves when a certain compound is present in them.
This technology is called plant nanobionics. Naturally, most of us don’t worry about explosives, and military entities or peacekeepers have others means of rooting out land mines. These explosive chemicals just so happened to be what was used in the nanobionic’s experiment everyone’s talking about.
More practical uses of plant nanobionics would be monitoring land for pollutants that would, when present, make the leaves glow. Quite conveniently, you can leave the camera in place and get a text message from the camera when/if the leaves start glowing.
For instance, you could plant some of this spinach on a location under threat of impending contamination, and monitor the environmental integrity of that area from afar. If the plant picks up a contaminant and starts to glow, you’d receive a remote signal. This includes the average citizen with access to a nanobionic spinach plant – no more relying on the trustworthiness of a government’s Environmental Impact Assessment!
And it only takes these plants 10 minutes to detect a chemical. So you can slip a slip of spinach into the ground and count to 600. Why spinach? Why are we using spinach for this? No real reason, beyond the fact it’s not a finicky or fragile species to work with.