First in human history and a milestone in lunar and space exploration, scientists from the University of Florida have grown plants in soil from the Moon.
In a paper published in the journal Communications Biology, the researchers showed that plants can successfully sprout and grow in lunar soil. The study also investigated how plants respond biologically to the Moon’s soil, also known as lunar regolith, which is radically different from soil found on Earth.
The research comes as the Artemis Program plans to return humans to the Moon, Rob Ferl, one of the study’s authors and professor of horticultural sciences in the UF Institute of Food and Agricultural Sciences said that Artemis will require a better understanding of how to grow plants in space.
Anna-Lisa Paul, another author and a research professor of horticultural sciences in UF/IFAS, noted: “Plants helped establish that the soil samples brought back from the moon did not harbor pathio gens or other unknown components that would harm terrestrial life, but those plants were only dusted with the lunar regolith and were never actually grown.”
Paul and Ferl are internationally recognized experts in the study of plants in space.
THE DESIGN AND METHOD
Ferl and Paul designed a deceptively simple experiment: plant seeds in lunar soil, add water, nutrients and light, and record the results. They just had only 12 grams — just a few teaspoons — of lunar soil with which to do this experiment. On loan from NASA, this soil was collected during the Apollo 11, 12 and 17 missions to the Moon. To grow their tiny lunar garden, the researchers used thimble-sized wells in plastic plates normally used to culture cells. Each well functioned as a pot. Once they filled each “pot” with approximately a gram of lunar soil, the scientists moistened the soil with a nutrient solution and added a few seeds from the Arabidopsis plant.
Arabidopsis is widely used in the plant sciences because its genetic code has been fully mapped. Growing Arabidopsis in the lunar soil allowed the researchers more insight into how the soil affected the plants, down to the level of gene expression. As points of comparison, the researchers also planted Arabidopsis in JSC-IA, a terrestrial substance that mimics real lunar soil, as well as simulated Martian soils and terrestrial soils from extreme environments. The plants grown in these non-lunar soils were the experiment’s control group. Well, ahead of the experiment, the researchers were not sure if the seeds planted in the lunar soils would sprout. But nearly all of them did. “We were alarmed. We did not predict that,” Paul said.
They also saw that some of the plants grown in the lunar soils were smaller, grew more slowly or were more varied in size than their counterparts.
At the genetic level, the plants were pulling out the tools typically used to cope with stressors, such as salt and metals or oxidative stress, so we can infer that the plants perceive the lunar soil environment as stressful.” Paul said.
“Ultimately, we would have to use the gene expression data to help address how we can ameliorate the stress responses to the level where plants – particularly crops are able to grow in lunar soil with very little impact to their health,” the scientist said.
“How plants respond to lunar soil may be linked to where the soil was collected,” said Ferl and Paul, who collaborated on the study with Stephen Elardo, an assistant professor of geology at UF For instance, the researchers found that the plants with the most signs of stress were those grown in what lunar geologists call mature lunar soil. These mature soils are those exposed to more cosmic wind, which alters their makeup. On the other hand, plants grown in comparatively less mature soils fared better.