Biochemical Components of 56 Tea Plant Resources in Guangdong Luokeng Crocodile Lizard National Nature Reserve

Purpose To explore the characteristics of the biochemical components of tea plant resources growing under relatively primitive conditions in Guangdong Luokeng Crocodile Lizard National Nature Reserve, and screen for specific genetic resources.

Methods A total of 56 tea plant individuals were used as the research object, the composition of amino acids, catechins and alkaloids were detected by high performance liquid chromatography, and the contents of moisture, water extract, free amino acids, and tea polyphenol were determined according to the methods specified in the national standard. Subsequently, descriptive statistics analysis, factor analysis, cluster analysis and difference analysis were performed.

Results 1) The biochemical components of 56 resources had obvious commonalities, which were rich in water extract, tea polyphenol, free amino acids and caffeine. Theanine was the dominant amino acid. Most of individuals belonged to high caffeine resources. 2) The biochemical components of the resources in this area were significantly different from those of conventional tea varieties, among which, the content of epicatechin gallate (ECG) was higher than that of conventional tea varieties, and some individual plants had theacrine. These were closely related to the local special microclimate and the distribution of animals and plants. 3) The composition of non-ester catechin monomers and amino acid varied greatly in different plants, so the 56 resources could be clustered into five groups. Among them, the eight individuals in group I had the largest gap with other groups, there might be a distant genetic relationship. 4) One resource with amino acid content more than 5%, one resource with caffeine content less than 2%, three resources with epigallocatechin gallate content more than 10%, 13 resources with ECG content more than 5%, eight resources with theacrine content more than 1%, and two resources containing γ-aminobutyric acid were screened.

Conclusion The tea resources in this area are rich in substances and have high processing and utilization value. Meanwhile, their biochemical components are rich in diversity, they may come from different species, and it is expected to discover and breed more specific tea plant resources around there.