Abstract:

In order to scientifically and reasonably select new lines of high-quality Camellia tachangensis, seven dominant strains of C. tachangensis were used as the materials in this study, ‘Fuding Dabaicha’ as the check, to comprehensively analyze and systematically evaluate the leaf bud traits, basic quality traits, catechin components and amino acid components. The leaf bud traits of the seven lines were medium leaf or large leaf species with slightly elongated yellow-green bud leaves of shallow and blunt leaf teeth, without pilose or less pilose, in elliptic or long elliptic, with hard and crisp texture, and glossy leaf thickness.. Biochemical analysis showed that the water extracts, free amino acids and ECG contents of the seven lines were high, indicating that they were excellent tea germplasm resources. The variation range of water extract content, caffeine content, tea polyphenols content, amino acid content, crude fiber content, vitamin C content, protein content and water-soluble carbohydrate content was 47.02%-48.70%, 2.91%-3.42%, 19.03%-21.07%, 4.07%-4.84%, 7.43%-8.38%, 208.00-332.00 mg/100 g, 33.82-35.07 mg/100 g, 3.23%-3.85%, the variation range of phenol-ammonia ratio was 3.98-5.04. The content of main catechin was in the order of C>ECG>EC>EGCG>EGC, the content of C and ECG was high, which was significantly higher than that of CK, and the variation range was 5.25%-9.02% and 6.11%-7.64%, respectively. The contents of EGCG and EGC were low, which were significantly lower than that of CK, and the variation range was 0.08%-1.44% and 0.05%-0.31%, respectively. A total of 19 amino acids were detected in the seven lines. There were some differences in the types and contents of amino acids among different components. The five amino acids with high content were theanine>glutamic acid>arginine>aspartic acid>serine, accounting for more than 82.14 % of the total amino acids. There was a certain correlation between morphological traits and bochemical components. The results of principal component analysis based on 16 biochemical components showed that 16 biochemical components were simplified to 5 factors, and the cumulative contribution rate was 95.68%, which contained most of the star information of all traits. Comprehensive Evaluation based on biochemical components showed that L₁₇, L₂₂ and L₀₆ ranked the top three among the seven lines. In this study, dominant lines L₀₆, L₁₇ and L₂₀ with potential characteristics of suitable green tea and lines L₁₂, L₁₃, L₂₁ and L₂₂ with potential characteristics both for black and green tea production were identified.

Key words: Camellia tachangensis, leaf bud traits, biochemical components, identification