大厂茶优势株系芽叶性状与生化成分的鉴定与评价

为科学合理选育出优质大厂茶无性系新品种（系），本研究以7个大厂茶优势株系为研究材料，以福鼎大白茶为对照，对其芽叶性状、主要生化成分、儿茶素组分及氨基酸组分进行综合分析和系统评价。结果表明，7个大厂茶优势株系芽叶性状呈中叶或大叶种，芽叶黄绿，无茸毛或少毛，叶椭圆或长椭圆形，叶质硬脆，叶齿浅且钝，叶面微隆，叶缘微波，叶厚有光泽等特征。生化成分分析表明，7个大厂茶优势株系水浸出物含量、游离氨基酸含量和ECG含量较高，属优良茶树种质资源。其水浸出物含量、咖啡碱含量、茶多酚含量、游离氨基酸含量、粗纤维含量、维生素C含量、蛋白质含量、水溶性碳水化合物含量变化范围分别为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%，酚氨比变化范围为3.98~5.04。主要儿茶素组分含量大小顺序为C>ECG>EC>EGCG>EGC，C和ECG含量较高，均显著高于CK，其变化范围分别为5.25%~9.02%和6.11%~7.64%，而EGCG和EGC含量较低，显著低于CK，其变化范围分别为0.08%~1.44%和0.05%~0.31%。7个大厂茶优势株系共有19种氨基酸被检出，氨基酸各组分之间的种类和含量都存在一定的差异性，含量较高的5个氨基酸组分依次是茶氨酸>谷氨酸>精氨酸>天冬氨酸>丝氨酸，占氨基酸总量的82.14%以上。各芽叶性状与生化成分之间有一定相关性。基于16个生化成分的主成分分析显示，16个生化成分被简化为5个因子，累计贡献率达95.68%，包含16个生化成分的大部分信息。综合评价显示，7个大厂茶优势株系中排名前三的依次是L₁₇、L₂₂和L₀₆，为大厂茶新品种（系）的选育奠定基础。本研究还鉴定出L₀₆、L₁₇和L₂₀ 3个具有适制绿茶潜在特性的大厂茶优势株系，L₁₂、L₁₃、L₂₁和L₂₂ 4个具有红绿茶兼制潜在特性的大厂茶优势株系。

Identification and Evaluation on Leaf Bud Traits and Biochemical Components of Dominant Strains of Camellia tachangensis

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.