Chickpeas grown and harvested using dirt from moon for first time

By Stephen Beech

Chickpeas have been successfully grown and harvested using “moon dirt” for the first time.

The breakthrough is a "giant leap" in understanding what it will take to grow food on the lunar surface, say American scientists.

How humans would survive long-term and what they would eat on the moon is the focus of attention with NASA planning to return to Earth's only satellite with the upcoming Artemis II mission.

Now scientists from The University of Texas at Austin say the answer might be chickpeas after they grew and harvested the protein-rich pulses in simulated moon dirt.

The study, published in the journal Scientific Reports, was conducted along with colleagues from Texas A&M University.

Principal investigator Dr. Sara Santos, of the University of Texas Institute for Geophysics (UTIG), said: “The research is about understanding the viability of growing crops on the moon.

“How do we transform this regolith into soil? What kinds of natural mechanisms can cause this conversion?”

She said lunar regolith - the technical term for moon dirt - lacks the microorganisms and organic material required for plants to live.

But while it contains essential nutrients and minerals for plants to grow, it also contains heavy metals that could be toxic to plants.

The research team used simulated moon dirt from Exolith Labs, a mix that models the composition of lunar samples brought back by Apollo astronauts.

To create ideal growing conditions in the moon dirt, the team added vermicompost - a byproduct of red wiggler earthworms that’s rich in essential plant nutrients and minerals and has a diverse microbiome.

The researchers said the earthworms create the product by consuming organic material such as food scraps or cotton-based clothes and hygiene products that would be otherwise thrown away on missions.

The team then coated the chickpeas with the fungi arbuscular mycorrhizae before planting.

Dr. Santos said the fungi and chickpeas work "symbiotically" - with the fungi taking up some essential nutrients needed for growth while reducing the uptake of heavy metals.

After that, the research team planted the chickpeas in a mixture of moon dirt and vermicompost in varying proportions.

They found that mixtures of up to 75% moon dirt successfully produced harvestable chickpeas.

However, any higher percentage of moon dirt caused issues, with the plants showing signs of stress and early death.

The stressed plants survived longer than chickpeas that weren’t inoculated with fungi, showing the importance of their importance to plant health.

The research team also found that the fungi were able to colonise and survive in the simulant, suggesting they would only need to be introduced one time in a real-world growing setting.

Although harvesting the chickpeas is a major milestone, the researchers say how the pulses taste and safety is still an open question.

They still need to determine the nutritional content of the chickpea and ensure toxic metals were not absorbed during the growing process.

Study first author Jessica Atkin, a doctoral candidate at Texas A&M University, added: "We want to understand their feasibility as a food source.

“How healthy are they? Do they have the nutrients astronauts need?

"If they aren’t safe to eat, how many generations until they are?”