If we ever leave Earth, farming off-world will be crucial, but Mars, the Moon and other planetary bodies just don’t have nutrients in the ground. A new study from the University of Zurich has an idea to get around the problem: mycorrhiza, when plants and fungi form symbiotic relationships.
Mycorrhiza are extremely tiny fungi themselves, made of microscopic threads called hyphae. These hyphae threads are connected through a web called a mycelium. Mycorrhizal mycelium networks can measure hundreds of miles when unfolded, and they connect to other plants through what’s called a common mycorrhizal network. Crucially, in this network, mycorrhiza begin bartering with the newly-connected plants. They offer up proteins like water, nitrogen, and phosphates in exchange for the plant’s excess sugar.
For Lorenzo Borghi of the University of Zurich and Marcel Egli of the Lucerne University, the process seems custom-built for space. Using a 3D random positioning machine to simulate microgravity, they were able to cultivate petunias and mycorrhizal fungi under low gravity conditions. They chose petunias because, as members of the Solanaceae family of plants, they share similarities with other nightshade plants like potatoes, tomatoes and eggplants.
There’s difficulty to this process: Microgravity affects mycorrhization and reducing how much protein the petunias could accept. But by introducing a chemical compound known as strigolactone to the process, they were able to counteract the effect. Strigolactone is a naturally occurring compound within plants, used to encourage relationships between the plant and outside microbes. By artificially enhancing the strigolactone within these plants, the petunias were able to bloom.
In order to get crops such as tomatoes and potatoes to grow in the challenging conditions of space, it is necessary to encourage the formation of mycorrhiza,” says Borghi, speaking in a press statement. “This seems to be possible using the strigolactone hormone. Our findings may therefore pave the way for the successful cultivation in space of the types of plants that we grow on Earth.”
Until then, space farming is already being used in the here and now—to grow weed.
Source: University of Zurich
Originally posted on Popular Mechanics