Genotype selection and microbial partnerships influence chickpea establishment in lunar regolith simulant

Authors: ATKIN, JESSICA - Texas A&M University; SKABELUND, HIKARI - Texas A&M University; PIERSON, ELIZABETH - Texas A&M University; ZHEN, SHUYANG - Texas A&M University; Vandemark, George; GENTRY, TERRY - Texas A&M University

Submitted to: Frontiers in Astronomy and Space Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/30/2025
Publication Date: 12/9/2025
Citation: Atkin, J., Skabelund, H., Pierson, E., Zhen, S., Vandemark, G.J., Gentry, T. 2025. Genotype selection and microbial partnerships influence chickpea establishment in lunar regolith simulant. Frontiers in Astronomy and Space Sciences. 12:1670807. https://doi.org/10.3389/fspas.2025.1670807.
DOI: https://doi.org/10.3389/fspas.2025.1670807

Interpretive Summary: Long-term expeditions of humans to Earth's Moon for research and to develop infrastructure for more permanent space colonization will be safer and less dependent on re-supply if more food can be produced using lunar resources. Lunar “soil”, referred to technically as lunar “regolith”, is a poor substitute for earthly soil, lacking in structure, nutrients, organic matter, and soil microbes, while having poor water permeability and high concentrations of phytotoxic heavy metals. Despite these qualities, there is increasing interest in growing plants for food production and resource recycling using lunar regolith as a growth substrate. Legumes, such as chickpeas, are of special interest because their roots can be colonized by beneficial soil bacteria that produce nitrogen fertilizer in plant roots. The objective of this study was to evaluate 16 different chickpea varieties and USDA breeding lines for the ability to grow in simulated lunar regolith and be colonized by the beneficial, nitrogen fertilizer producing, soil bacteria Mesorhizobium ciceri. Seeds were sown in a growth sustrate that consisted of 25% compost-75% simulated lunar regolith. The different chickpea entries varied in how much above-ground and below-ground plant material they produced. The recent USDA variety 'USDA Quinn' produced the most biomass of all entries. Most interesting, all the different chickpea entries could be colonized by the benefical, nitrogen fertilizer producing soil bacteria in the simulated lunar regolith growth matrix. These results suggest that beneficial plant-microbe interactions can operate and crops can be produced using growth sustrates largely composed of lunar materials.

Technical Abstract: Sustainable food production is essential for long-duration Lunar missions, driving the development of in situ resource utilization strategies that use lunar regolith (LR) as a growth substrate for food crop cultivation. Although LR contains essential plant nutrients, it lacks organic matter and beneficial microbes. Its poor structure, low nitrogen content, and the presence of phytotoxic metals pose major challenges for plant germination, establishment, health, and successful fruit/seed production. On Earth, plant health and productivity are aided by microbial symbioses with mycorrhizal fungi, diazotrophic bacteria, and other rhizosphere colonizing organisms that facilitate nutrient availability, detoxify metals, and improve soil structure. This study evaluated seeding establishment, early plant development, and effective microbial symbiosis with rhizobia (Mesorhizobium ciceri) in 16 chickpea (Cicer arietinum) genotypes grown in vermicompost amended lunar regolith simulant (LRS) LHS-1. Chickpea is an ideal candidate for Lunar agriculture because it is a nutritionally dense food source and forms symbiotic relationships with arbuscular mycorrhizal fungi and rhizobia. Genotypes exhibited distinct growth strategies under LRS conditions, with considerable variation in total biomass production, differing by as much as 116 percent across genotypes, and in aboveground and belowground allocation. Notably, most genotypes showed strong nodulation with Mesorhizobium ciceri, suggesting potential for biological nitrogen fixation. These results inform breeding strategies for chickpea cultivars adapted to regolith-based systems and agriculture in challenging environments.