Comparative analysis of chloroplast genomes indicated different origin for Indian tea (Camellia assamica cv TV1) as compared to Chinese tea

Abstract

Based upon the morphological characteristics, tea is classified botanically into 2 main types i.e. Assam and China, which are morphologically very distinct. Further, they are so easily pollinated among themselves, that a third category, Cambod type is also described. Although the general consensus of origin of tea is India, Burma and China adjoining area, yet specific origin of China and Assam type tea are not yet clear. Thus, we made an attempt to understand the origin of Indian tea through the comparative analysis of different chloroplast (cp) genomes under the Camellia genus by performing evolutionary study and comparing simple sequence repeats (SSRs) and codon usage distribution patterns among them. The Cp genome based phylogenetic analysis indicated that Indian Tea, TV1 formed a different group from that of China tea, indicating that TV1 might have undergone different domestications and hence owe different origins. The simple sequence repeats (SSRs) analysis and codon usage distribution patterns also supported the clustering order in the cp genome based phylogenetic tree.

From the Wild to the Cup: Tracking Footprints of the Tea Species in Time and Space

“…Bayesian clustering and phylogenetic analyses in these studies (36,37) indicated that the Chinese CSA tea may have been domesticated from C. grandibracteata, and CSS from C. ptilophylla or C. leptophylla. These findings were generally consistent with results of plastomic analyses of species in Camellia/Theaceae (26,(38)(39)(40), further reinforcing the view that C. grandibracteata and C. leptophylla might have been involved in the domestication of tea. Although the above studies did shed some light on the evolutionary origin of tea, controversies still abound; for instance, the phylogeny of Huang et al (36) indicated that CSS and CSA might have undergone independent domestication from two different progenitors, while Rawal et al (40) suggested that CSS may have descended from CSA.…”

“…The early speculations by Ward (22) about the origin of CSS and CSA were later partly supported by some empirical genetic/genomic studies (18,25,26), which demonstrated that cultivated CSS and CSA might have different geographical origins. An emerging idea, however, is that CSA in China and India are genetically distinct (though morphologically similar), indicating independent geographic and evolutionary origin for the two CSA groups (18,26).…”

“…The early speculations by Ward (22) about the origin of CSS and CSA were later partly supported by some empirical genetic/genomic studies (18,25,26), which demonstrated that cultivated CSS and CSA might have different geographical origins. An emerging idea, however, is that CSA in China and India are genetically distinct (though morphologically similar), indicating independent geographic and evolutionary origin for the two CSA groups (18,26). Although genetic data could be a powerful tool for inferring the geographic origin of a domesticated species, they only distinguish individuals based on their genetic similarity rather than their geographical origin [e.g., (27)], hence presenting a hurdle for meaningful inferences on geographic origin.…”

“…The existence of wild tea trees [C. sinensis (L.) O. Kuntze] in China and India could mean that tea was domesticated directly from these wild tea trees, as opposed to the popular view that non-tea wild species were involved [e.g., (26), and references therein]. However, the plausibility of involvement of a non-tea ancestor seems to be validated by the fact that some non-tea Camellia species such as C. crassicolumna Chang, C. gymnogyna Chang, C. tachangensis F.C.…”

Tea and tea drinking: China’s outstanding contributions to the mankind

“…According to cluster analysis, various types of intermediate hybrids and spontaneous polyploids are found because tea trees can easily hybridize, and there is likely just a single place/area of origin for Camellia sinensis on earth. This place is believed to be the adjoining area of the Yun Nan and Si Chuan provinces of China, India, and northern Burma [ 35 ].…”