Mushrooms and compost helped legumes thrive in harsh conditions
Home-grown chickpeas could be on the menu of future astronauts. With the help of compost and symbiotic mushrooms, chickpea plants grow and produce seeds in simulated lunar soil, researchers report March 5 Scientific reports.
“I’m obsessed with the plant,” says fluid dynamics scientist Sara Oliveira Santos of the University of Texas at Austin. “The fact that we’re able to make these additions and help the plant get to a stage where it’s producing seed, I think that’s really important.”
Teaching the inhabitants of the Moon to feed themselves is a somewhat pressing problem. NASA’s Artemis program plans to bring humans back to the moon in the next few yearswith the ultimate goal of living there for the long term. But lunar dirt, called regolith, is as fine as baby powder, metallic, sticky and sharp and lacks essential nutrients like nitrogen. “This is an unmodified hazard,” says space biologist Jess Atkin of Texas A&M University in College Station. “It’s the worst. It’s horrible.”
Scientists have had some success growing plants true lunar regolith Apollo missions. But the plants absorbed toxic metals and grew slowly, showing signs of stress.
Atkin and Santos wondered whether techniques for removing toxins from terrestrial soils could help plants not only grow, but also thrive in lunar soil. The researchers and their colleagues dusted chickpeas – chosen for their hardiness and high protein content – with powder. arbuscular mycorrhizal fungi. These fungi help plants’ taproots branch out and reach more soil while helping to sequester heavy metals away from the plant.
The team planted the seeds in various mixtures of lunar regolith simulant, a mixture of geological materials from Earth that mimics the composition of lunar dirt, and vermicompost, a fertilizer excreted by red worms that eat food waste.
Chickpea plants grew for weeks to months and produced flowers and seeds in soil mixtures containing up to 75 percent lunar simulant. All plants grown in lunar soil showed signs of stress compared to plants grown in terrestrial conditions. But even when stressed, plants treated with fungi lived two weeks longer than those without fungal help.
Atkin hopes that mushrooms and vermicompost could help create stable, healthy lunar soil in which future astronauts can grow any crop they choose. “The plants are amazing, it’s great to be able to get seeds,” she said. “But they are actually the host of the transformation in the soil.”
Researchers are doing more testing to see if the seeds can produce new generations of chickpea plants and if those plants are safe to eat. “I asked to eat it, but she [Atkin] said no,” Santos said.
If they prove safe, Atkin says, “I’ll be the first to make moon hummus.” »