Alleviation of salt stress in strawberries by hydrogen-rich water: Physiological, transcriptomic and metabolomic responses

The increasing impacts of climate change and intensified human activities exacerbate soil salinization, posing significant challenges to agricultural productivity. Therefore, addressing salt stress in crops is a critical area of research. In this study, strawberry seedlings (Fragariaxananassa Duch. 'Benihoppe') were used to investigate the alleviating effects of hydrogen-rich water (HRW) on salt stress through integrated transcriptomic and metabolomic analyses. HRW treatment was found to significantly enhance plant growth, notably increasing root biomass by 49.50%. Additionally, HRW modulated key parameters, including the levels of soluble sugars, malondialdehyde (MDA), and antioxidant enzyme activities, while promoting K+ uptake and Na+ exclusion. Transcriptomic analysis revealed that HRW induced the expression of genes associated with ion transport, antioxidant defence, and cell wall biosynthesis in roots. Metabolomic profiling identified phenolic acids, flavonoids, and amino acids as critical metabolites in HRW-mediated salt stress mitigation. Integrated multi-omics analysis highlighted two key metabolic pathways, phenylpropanoid biosynthesis and amino and nucleoside sugar metabolism, pivotal to the observed protective effects. This study provides molecular insights into the mechanisms by which HRW alleviates salt stress in strawberry seedlings, underscoring the potential of hydrogen gas applications in sustainable agriculture.