Plants grow in lunar regolith

The extent to which plants can enhance human life support on other worlds depends on the ability of plants to thrive in extraterrestrial environments using in situ resources. Using samples from Apollo 11, 12 and 17, we show that the terrestrial plant Arabidopsis thaliana germinates and grows in diverse lunar regoliths. However, our results show that growth is challenging; the lunar regolith plants were slow to develop, expressed genes indicative of ionic stresses, and many showed severe stress morphologies. Therefore, although in situ lunar regolith can be useful for plant production in lunar habitats, they are not benign substrates. The interaction between plants and lunar regolith will need to be further elucidated, and likely mitigated, to enable efficient use of lunar regolith for life support. Overall design: Arabidopsis thaliana (Col-0) was grown in lunar regolith from three different mission sites: Apollo 11, Apollo 12 and Apollo 17. The plants were grown completely within the regolith as a growth substrate and compared to plants grown in an identical fashion in a lunar simulant (JSC-1A) as the control. Comparisons between and among lunar regoliths, and the simulant controls, included morphology and development, and transcriptomic responses.