The Quality Evaluation of Tea (Camellia sinensis) Varieties Based on the Metabolomics

Abstract

The identification and evaluation of tea [Camellia sinensis (L.) O. Kuntze] germplasm resources are of great significance for tea plant breeding. In recent years, various methods, such as morphology, biochemistry, molecular markers, and sensory evaluation, have been used to evaluate the tea germplasm resources. However, the evaluation of tea germplasms based on metabolomics is rarely reported. In this study, we first measured the main agronomic characters and biochemical components of tea young shoots in spring, and then analyzed the metabolic profiles using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography with tandem mass spectrometry (LC-MS/MS). The results indicate that tea germplasm accessions QN3 and QN38 had excellent agronomic traits with early germination and high yield compared with HM. The biosynthesis of flavonoids in young shoots of QN3 was more vigorous, especially for the biosynthesis of epigallocatechin gallate (EGCG) and epicatechin gallate (ECG). Accession QN3 had highest content of luteoloside, myricetin and rutin, whereas QN38 had highest content of most amino acids. On the basis of sensory quality evaluation, accession QN3 and QN38 all had higher total quality scores. By using these approaches, we found that QN3 and QN38 are excellent breeding materials with high yield and high quality for making green teas. We also believe that the evaluation system constructed by the approaches described here is suitable for the identification of tea germplasms.