Stress and light spectral quality influence the transcriptome of a tomato crop on the International Space Station

Genes associated with stress responses, hormonal signaling, and metabolic pathways were prominently upregulated in spaceflight-grown tissues. Gene ontology and KEGG pathway enrichment analyses highlighted critical roles for oxidative stress response, secondary metabolite biosynthesis, and hormonal regulation. Additionally, red rich lighting appeared to stabilize gene expression patterns, while blue rich lighting induced greater variability across conditions.

Notably, spaceflight exhibited extensive adventitious roots formation, with gene clusters enriched in antioxidant metabolism, cell wall remodeling, and stress adaptation processes. Leaf tissues demonstrated distinct transcriptional signatures under flight and ground conditions, with blue rich lighting enhancing stress responsive pathways and red rich lighting favoring metabolic stability. This study provides novel insights into the molecular mechanisms underlying plant adaptation to spaceflight and variable lighting conditions, emphasizing the importance of tailored environmental control for optimizing crop production in space.

These findings could have implications for developing resilient plant varieties suitable for extreme environments, both in extraterrestrial settings and on Earth.