连南茶树资源的生化成分多样性分析

目的]分析广东连南茶树种质资源生化成分的多样性,为茶树新品种选育提供科学依据.方法]检测广东连南县45份茶树资源的氨基酸、茶多酚、生物碱、酚氨比等主要生化成分指标,鉴定评价其遗传多样性.结果]连南茶树资源的生化成分存在丰富的多样性和变异性,其中,变异系数最大的是可可碱含量(146.39%),其次是儿茶素没食子酸酯(CG)和表儿茶素没食子酸酯(ECG)含量,分别为115.71%和108.20%,变异系数最小的是水浸出物含量,为12.14%.通过主成分分析,发现第一主成分和第二主成分的累计贡献率分别为77.284%和93.441%,包含所有性状的大部分信息.综合比较结果表明,可从45份茶树资源中筛选出一批生化成分特异的资源,其中,高氨基酸资源(>5.00%)4份,高茶多酚资源(>34.00%)14份,低咖啡碱资源(<1.00%)2份;在高水浸出物资源中,儿茶素总量和酯型儿茶素含量较高的资源有12份(涡水茶树群体中有10份,黄连茶树群体中有2份).结论]广东连南茶树资源生化成分多样性丰富,变异系数大,具有丰富的遗传多样性和明显的地域独特性;筛选出的13份高茶多酚资源及其他特殊资源可作为茶叶深加工和育种的基础材料.

Diversity of biochemical components for tea germplasm resources in Liannan

Objective]Biochemical components of tea germplasm resources in Liannan,Guangdong was analyzed to offer scientific references for new tea variety breeding.Method]Main biochemical components including amino acids, tea polyphenols,alkaloid and ratio of tea polyphenols to amino acids(TP/AA)were detected from 45 wild tea plants located in Liannan,Guangdong,and their genetic diversity was also evaluated.Result]The biochemical diversity and variation were high in Liannan tea germplasms. Variation coefficient of theobromine was the largest(146.39%),and followed by catechin gallate(CG)(115.71%)and epigallocatechin gallate(ECG)(108.20%). Variation coefficient of water extract was the lowest(12.14%). In principal component analysis,accumulative contribution rates of first principal component and second principal component were 77.284%and 93.441%,including most information about all traits. With comprehensive comparison,a group of germplasms with special biochemical components were selected. Among them,four tea germ-plasms contained high amino acids content(>5.00%),fourteen resources had high tea polyphenols content(>34.00%)and two with low caffeine content(<1.00%). Among resources with high water extract content,twelve resources contained high total catechin content and ester catechin content(ten from Woshui tea population and two from Huanglian tea population).Conclusion]Tea germplasm resources in Liannan,Guangdong contains diverse biochemical components, large coefficient of variation ,and feature genetic diversity and obvious regional uniqueness. The selected thirteen tea resources with high tea polyphenol content and other special tea resources can be used as basic materials for tea leaf deep-processing and variety breeding.