Energy metabolism contributes to cultivar-dependent cadmium accumulation in Ipomoea aquatica

Cadmium (Cd) contamination poses serious risks to agriculture and food safety. While previous studies have focused on Cd detoxification and transport, the role of energy metabolism in Cd accumulation remains unclear. This study examined cultivar-dependent Cd accumulation in Ipomoea aquatica, comparing a high-Cd-accumulating cultivar (T308) with a Cd pollution-safe cultivar (QLQ). Under Cd stress, T308 showed higher Cd translocation to shoots, associated with enhanced energy metabolism, including increased activity of tricarboxylic acid (TCA) cycle enzymes and mitochondrial electron transport chain (mETC) complexes. Integrated proteomic and metabolomic analyses showed coordinated regulation of carbon metabolism, with key enzymes (e.g., α-ketoglutarate dehydrogenase, citrate synthase) showing higher activity in T308. Additionally, higher levels of key metabolites, such as pyruvate, were observed in T308, along with increased ATP content. These findings suggest that enhanced energy metabolism in T308 may contribute to more efficient Cd translocation, providing potential insights for breeding Cd-safe cultivars.