Cultivation of Salicornia lagascae in High-NaCl Liquid Medium Induces a Metabolic Reprograming and Enhances Micropropagation Performance

Abstract This study establishes the first efficient in vitro micropropagation protocol for the halophyte Salicornia lagascae and provides new insights into its responses to salinity and culture system conditions. Moderate salinity enhanced explant proliferation, with 30 g L⁻ 1 NaCl identified as the optimal concentration, under which explants maintained stable photosynthetic performance; explants accumulated Na⁺ in a concentration-dependent manner during salt tolerance screening. Liquid culture systems showed clear advantages over solid media, promoting enhanced micronutrient accumulation, improved rhizogenesis, and greater plant growth after acclimatization, supporting their potential for efficient micropropagation. Metabolomic analyses revealed that medium consistency strongly induced a metabolic reprogramming, with solid media favoring sugar and phenylpropanoid accumulation. In contrast, liquid culture triggered the accumulation of some stress-related secondary metabolites, including betaine aldehyde in shoots and quercetin derivatives in roots, alongside the secretion of signaling molecules such as 7-epijasmonic acid into the medium. Collectively, these findings demonstrate that liquid culture induces stress-adaptive mechanisms and secondary metabolic pathways, providing an efficient platform for the micropropagation and selection of high salt-tolerant S. lagascae clones. Despite these advantages, further field validation and optimization of liquid culture systems will be required to facilitate translation to large-scale or commercial applications.