The glowing greenhouse of our dreams is still so very far away, but it just got a tantalising nudge closer.

Scientists have genetically engineered a plant with not just a visible glow, but a self-sustaining glow that lasts for the duration of the plant's life cycle.

It's a breathtaking improvement on previous glowing plants. It's brighter than previous genetically engineered tobacco plants, and it doesn't need to be fed with chemicals to maintain luminescence. Also, the duration of the glow is much longer than glowing plants produced using plant nanobionics.

Of course, we all immediately think of a breathtaking Avatar-style night garden, glittering and gleaming in the darkness, and - further into the future - reducing our dependence on electric lighting.

But glowing greenery could also help us understand the plants themselves - how their metabolism works, and how they respond to the world around them.

The team worked on two species of tobacco plant. And, unlike previous genetically engineered glowing plants, which used bioluminescent bacteria or firefly DNA, these plants were engineered using the DNA of bioluminescent fungi.

"Although bacterial bioluminescence genes can be targeted to plastids to engineer autoluminescence, it is technically cumbersome and fails to produce sufficient light," the researchers wrote in their paper.

"The caffeic acid cycle, which is a metabolic pathway responsible for luminescence in fungi, was recently characterised. We report light emission in Nicotiana tabacum and Nicotiana benthamiana plants without the addition of any exogenous substrate by engineering fungal bioluminescence genes into the plant nuclear genome."