Glutathione's role in mitigating cadmium stress in Pogostemon cablin: Insights from combined transcriptomic and metabolomic approaches

Cadmium (Cd) pollution poses a growing threat to plant growth. Although glutathione (GSH) is recognized for its potential to mitigate Cd-induced stress, its specific effects on alleviating such stress in Pogostemon cablin (patchouli) remain unclear. This study investigated physiological parameters and enzymatic activities across four treatment groups: control (CK), cadmium stress (Cd), glutathione (GSH), and glutathione with cadmium stress (GSH+Cd). Results revealed that chlorophyll a, b, and carotenoid levels in the GSH were approximately 20 % higher than those in the other groups. In contrast, antioxidant enzyme activity in the Cd decreased by about 15 %. Integrated transcriptomic and metabolomic analyses demonstrated that GSH mitigates Cd stress by influencing glycerophospholipid metabolism and flavonoid biosynthesis, with key roles attributed to dgkA1, dgkA2, and CCoAOMT1–4. In conclusion, GSH alleviates Cd stress in P. cablin by enhancing photosynthetic pigment synthesis, reducing reactive oxygen species (ROS) through improved enzymatic activity, and regulating metabolic pathways. These findings provide valuable insights for optimizing the cultivation and management of P. cablin under Cd stress conditions.