Objective Vastly diverse biochemical compositions of wild tea germplasms in Enshi, Hubei were analyzed to facilitate development and utilization of the natural resources.

Method HPLC and other analytical methods were applied to determine the contents of catechins, caffeine, and amino acids in 70 wild tea cultivars from 5 counties and cities in Enshi Prefecture, Hubei Province. Principal component and cluster analyses were conducted to categorize these germplasms based on biochemical diversity.

Result The indexes of genetic diversity on biochemistry of the germplasms ranged 1.50-3.09, averaging 2.41, and coefficients of variation 23.06%-96.47%, averaging 41.95%. Of the principal components, epicatechin gallate (ECG), epigallocatechin gallate (EGCG), and catechin (C), with eigenvalues greater than 1 cumulatively contributed 80.59% of total explanation. A cluster analysis grouped the 70 germplasms into 4 categories: Group I of a relatively high content in non-ester catechin, Group II of the lowest average content in catechin, Group III of the lowest in amino acid content, and Group IV of the highest ester catechins content. The cultivars, Zhongtai Village Dacheshan No.4, Dajichang Village Dacheshan No.1, and Zhongtai Village Dacheshan No.2 with high contents of ECG, EGCG, total catechins, and caffeine received the highest scores and were selected as the outstanding varieties by regression analysis.

Conclusion The biochemicals in the genetically richly divese 70 wild tea germplasms of Enshi varied significantly. ECG, EGCG, and caffeine were the crucial substances contributing to the tea quality and could be used as indicators for comprehensive evaluation. Accordingly, Zhongtai Village Dacheshan No.4, Dajichang Village Dacheshan No.1, and Zhongtai Village Dacheshan No.2 were selected as potential candidates for breeding new varieties.