Silicon Is Linked to Tea Quality Through Alteration Aluminum Uptake and Translocation in Camellia sinensis L.

Aluminum (Al) is involved in almost all aspects of abiotic stress and is supposed to play a crucial role in tea quality. Both exogenous Al and silicon (Si) influence Al uptake, translocation, and accumulation in considerable quantify plants. However, the relationship between Si-mediated Al uptake and tea quality has not been systematically investigated. In this study, we found that Si supply affected caffeine, free amino acids, and Al in young leaves and tea infusion. Si increased the Al content in secondary roots, but it also decreased the ratio of young leaves to secondary roots, with this decreasing ratio becoming more pronounced at higher Al supply levels. Furthermore, Si reduced the Al absorption rate at a constant pH and down-regulated the value of the Michaelis constant (Km). These analyses demonstrate that Si regulates the Al absorption rate and distribution in tea plants-that is, the ratio of Al content in young tea leaves to that in the secondary roots, thereby influencing the concentrations of caffeine, free amino acid, and Al solubility in tea infusions.