The reduction of tea quality caused by irrational phosphate application is associated with anthocyanin metabolism

Abstract

Phosphorus (P) is the second most limiting nutrient for plant growth.Previous studies suggested that Psubstantiallyaffects the yield and quality of tea by affecting root growth, the decomposition and metabolism of minerals and metabolites in plants.Thus,the environmental pollution and degradation of crop quality caused by irrational fertilizationis of increasing interest by researchers worldwide. To revealthe effects of Pfertilizationon tea quality and metabolism of key quality components, three Pfertilization levels (excessive, appropriate, and deficient application) were applied to tea plants usingpot experiment.Contents of P, potassium, polyphenols, amino acids and anthocyanins in the leaves or soil were quantified. The sensory quality of tea infusion was reduced under irrational (excessive or deficient) Pfertilization. Under Pdeficiency, the total contents of polyphenols and anthocyanins in the leaves were strongly increased compared with those of the control. A high soil Pcontent (excessive) inhibited polyphenol accumulation, but induced the accumulation of certain anthocyanins, such as peonidin-3-O-sambubioside-5-O-glucoside and peonidin-3-O-5-O-(6-O-p-coumaryl)-diglucoside. These results suggested that the reduction of tea quality caused byirrational P application is associated with anthocyanin metabolism,which providesa scientific basis for improving Pfertilization strategyin tea plantation.