2018 ASHS Annual Conference

Tea is the most widely consumed beverage in the world next to water. Knowledge of genetic diversity is fundamental for improving, conservation and utilization of tea plant [Camellia sinensis (L.) O. Kuntze ] genetic resources. However, the distribution and structure of genetic diversity in the primary gene pool of tea plant is poorly understood. One hundred fifty Single Nucleotide Polymorphism (SNP) markers were used to assess the genetic diversity in 710 tea accessions covering a wide geographic origin and morphological variation. Multivariate and Bayesian clustering analysis revealed four distinctive genetic lineages of tea germplasm, corresponding to small leaved China type and three broad leaved Assam type viz. Indian Assam, Chinese Assam, and Cambod Assam. The four groups can freely inter-bred, resulting in a wide array of hybrids in farmer fields and ex situ tea collections. The result of present study demonstrates, that there are four main genetic lineages in the primary gene pool of tea plant. Each lineage has its independent origin and site of domestication. Our result also reaffirms the old postulate that Cambod Assam (C. assamica sub spp lasiocalyx (Planchon ex Watt.) or "Southern form") is a distinctive member of Assam tea C. assamica (Masters). Research on assessment of intra-varietal genetic diversity and history of domestication, focusing on small leaved China type, is also discussed.