Abstract: In order to investigate the effects of phosphorus aluminum interaction on various quality indicators of tea trees, this study treated tea seedlings with hydroponics and measured the contents of tea polyphenols, soluble sugars, free amino acids, caffeine, flavonoids, and other substances in the leaves. The changes in leaf biochemical indicators under phosphorus aluminum interaction treatment were analyzed. The results showed that the content of free amino acids, tea polyphenols, soluble sugars, caffeine, flavonoids, and other compounds decreased to varying degrees in the 0 mmol/L and 1 mmol/L phosphorus treatments and 4 mmol/L and 6 mmol/L aluminum treatments compared to that of the appropriate phosphorus and aluminum treatment. The unreasonable application of phosphorus and aluminum elements affected the synthesis of primary and secondary metabolites related to tea quality, which was not conducive to the formation of tea quality.

Key words: tea tree, hydroponics, phosphorus aluminum interaction, leaves, biochemical indicators