Objective Genetic diversity of the tea germplasms preserved at Shiting plantations in Nan’an was studied for promoting the utilization of the local specialty.

Methods SNP molecular marker technology was applied to analyze the genetic diversity and relationships of 17 tea germplasms from the Shiting plantations and 6 representative varieties from Fujian. HPLC and UPLC-MS/MS were employed to determine the contents of catechins and free amino acids in 10 selected samples for a comparison among the tea varieties.

Results Forty-four SNP loci suitable for identifying the tea plants were selected. An SNP fingerprint profile of the germplasms was constructed. The UPGMA evolutionary tree divided the 23 germplasms into 4 subgroups, which showed a close relation with Rougui and Qidan teas from northern Fujian. Significant differences were found on the contents of major amino acids and catechins among the varieties (P＜0.05) with total free amino acids from 8.46 mg·g⁻¹ to 32.66 mg·g⁻¹ and catechins ranging from 107.56 mg·g⁻¹ to 177.60 mg·g⁻¹. The germplasms coded ST2, ST3, ST6, and ST17 had high contents of EGCG or EGCG3"Me, while ST3 the most on amino acids and the least on catechin bitterness index.

Conclusion  Shiting plantations in Nan’an had a rich collection of tea germplasms that were closely related to those in northern Fujian. Among them, ST2, ST3, ST6, and ST17 teas had high contents of either EGCG or EGCG3"Me. ST3, specifically, appeared to be suitable for making green tea as well as in breeding programs.