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Plants have evolved several strategies to cope with the ever-changing environment. One example of this is given by seed germination, which must occur when environmental conditions are suitable for plant life. In the model system Arabidopsis thaliana seed germination is induced by light; however, in nature, seeds of several plant species can germinate regardless of this stimulus. While the molecular mechanisms underlying light-induced seed germination are well understood, those governing germination in the dark are still vague, mostly due to the lack of suitable model systems. Here, we employ Cardamine hirsuta, a close relative of Arabidopsis, as a powerful model system to uncover the molecular mechanisms underlying light-independent germination. By comparing Cardamine and Arabidopsis, we show that maintenance of the pro-germination hormone gibberellin (GA) levels prompt Cardamine seeds to germinate under both dark and light conditions. Using genetic and molecular biology experiments, we show that the Cardamine DOF transcriptional repressor DOF AFFECTING GERMINATION 1 (ChDAG1), homologous to the Arabidopsis transcription factor DAG1, is involved in this process functioning to mitigate GA levels by negatively regulating GA biosynthetic genes ChGA3OX1 and ChGA3OX2, independently of light conditions. We also demonstrate that this mechanism is likely conserved in other Brassicaceae species capable of germinating in dark conditions, such as Lepidium sativum and Camelina sativa. Our data support Cardamine as a new model system suitable for studying light-independent germination studies. Exploiting this system, we have also resolved a long-standing question about the mechanisms controlling light-independent germination in plants, opening new frontiers for future research., (Copyright © 2025 The Author(s). Published by Elsevier Inc. All rights reserved.)

Prebiotics might contribute to astronauts' health in space, yet their production in Bioregenerative Life Support Systems (BLSS) remains largely unexplored. Here, chicory ( Cichorium intybus L.) exhibited the most appropriate characteristics among seven candidate species as the ideal crop for space prebiotic production systems. Furthermore, we evaluated chicory's performance under different light intensities (250 μmol m -2 s -1 and 500 μmol m -2 s -1 of photosynthetically active radiation) and growing cycle lengths (76 and 91 days after sowing) to optimize prebiotic production. Our findings reveal chicory's remarkable adaptability to fully controlled growing conditions and its ability to accumulate high levels of inulin in the young taproot, despite the short growing cycle. The length of the growing period influenced the productivity of biomass and inulin, the latter depending more on taproot biomass than on inulin content. A growing area of 6.3 m 2 might be sufficient for a daily production of 12 g of inulin, the amount of "native chicory inulin" recognized by EFSA to promote health benefits in humans. These results establish important baselines for prebiotic production in BLSS or Controlled Environment Agriculture (CEA) and may be used to design fully controlled cropping systems for space and Earth based vertical farming facilities., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2025 The Authors. Published by Elsevier Ltd.)