Glowing plants might sound like the stuff of science fiction – but a team of MIT researchers just grew a crop of watercress that emits emit dim light for almost four hours. Postdoctoral researcher Seon-Yeong Kwak led a team of engineers and scientists to instill the plants with the same enzyme that makes fireflies sparkle. MIT chemical engineering professor Michael Strano said, “The vision is to make a plant that will function as a desk lamp – a lamp that you don’t have to plug in. The light is ultimately powered by the energy metabolism of the plant itself.”

Plant lamps or even tree street lights could brighten our world in the future thanks to recent research on glowing plants. The plants are illuminated by luciferase – the same enzyme that helps fireflies shine.
Luciferase acts on the molecule luciferin to give off light. The team put these three components into nanoparticle carriers to get them to the correct part of a plant. The scientists showed they can also turn off the light by adding nanoparticles with a luciferase inhibitor, so they think they could eventually create plants that stop emitting light in response to conditions like sunlight.
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Past experiments to create light-emitting plants attempted to genetically engineer plants to express the gene for luciferase, according to MIT. But it’s a process that takes a lot of work for very dim light – and it’s often limited to just one plant type.
The new MIT process can work on any kind of plant; so far the scientists have demonstrated it with watercress, kale, arugula, and spinach. They hope to be able to spray or paint the nanoparticles on leaves with future iterations, so trees or large plants could serve as light sources.
The journal Nano Letters published the research online in November. Scientists from the University of California, Riverside and the University of California, Berkeley contributed to the work.
Images via Seon-Yeong Kwak