Genetic diversity and domestication origin of tea plant Camellia taliensis (Theaceae) as revealed by microsatellite markers - PubMed (original) (raw)

Genetic diversity and domestication origin of tea plant Camellia taliensis (Theaceae) as revealed by microsatellite markers

Dong-Wei Zhao et al. BMC Plant Biol. 2014.

Abstract

Background: Tea is one of the most popular beverages in the world. Many species in the Thea section of the Camellia genus can be processed for drinking and have been domesticated. However, few investigations have focused on the genetic consequence of domestication and geographic origin of landraces on tea plants using credible wild and planted populations of a single species. Here, C. taliensis provides us with a unique opportunity to explore these issues.

Results: Fourteen nuclear microsatellite loci were employed to determine the genetic diversity and domestication origin of C. taliensis, which were represented by 587 individuals from 25 wild, planted and recently domesticated populations. C. taliensis showed a moderate high level of overall genetic diversity. The greater reduction of genetic diversity and stronger genetic drift were detected in the wild group than in the recently domesticated group, indicating the loss of genetic diversity of wild populations due to overexploitation and habitat fragmentation. Instead of the endangered wild trees, recently domesticated individuals were used to compare with the planted trees for detecting the genetic consequence of domestication. A little and non-significant reduction in genetic diversity was found during domestication. The long life cycle, selection for leaf traits and gene flow between populations will delay the emergence of bottleneck in planted trees. Both phylogenetic and assignment analyses suggested that planted trees may have been domesticated from the adjacent central forest of western Yunnan and dispersed artificially to distant places.

Conclusions: This study contributes to the knowledge about levels and distribution of genetic diversity of C. taliensis and provides new insights into genetic consequence of domestication and geographic origin of planted trees of this species. As an endemic tea source plant, wild, planted and recently domesticated C. taliensis trees should all be protected for their unique genetic characteristics, which are valuable for tea breeding.

PubMed Disclaimer

Figures

Figure 1

Figure 1

Camellia taliensis. (a) A branch with young fruit showing the five-loculed ovary, (b) wild tree, (c) wild trees after felling, (d)in situ recently domesticated trees, (e)ex situ recently domesticated trees, (f) planted trees. Picture (c) was taken by DWZ; all other pictures were taken by SXY.

Figure 2

Figure 2

Map of the sampling locations. The dots indicate wild populations, the squares indicate planted populations and the triangles indicate recently domesticated populations. The colours correspond to the model ancestry analysis.

Figure 3

Figure 3

Estimated population structure of the wild and recently domesticated C. taliensis with K = 3. The genome of each individual is represented by a vertical line that is divided into coloured segments in proportion to the estimated membership of each of three clusters: Cluster I (green), Cluster II (red) and Cluster III (blue).

Figure 4

Figure 4

Ancestry analysis of planted C. taliensis. Each genome of a planted individual is represented by a vertical line divided into coloured segments in proportion to the estimated ancestry of each source cluster.

Figure 5

Figure 5

Neighbor-joining phylogenetic relationships of 25 populations of C. taliensis. Mean F values for each population appear along lines. The colours correspond to model source clusters.

Similar articles

Cited by

References

    1. Ranere AJ, Piperno DR, Holst I, Dickau R, Iriarte J. The cultural and chronological context of early Holocene maize and squash domestication in the Central Balsas River Valley, Mexico. Proc Natl Acad Sci USA. 2009;106:5014–5018. doi: 10.1073/pnas.0812590106. - DOI - PMC - PubMed
    1. Heun M, Schäfer-Pregl R, Klawan D, Castagna R, Accerbi M, Borghi B, Salamini F. Site of einkorn wheat domestication identified by DNA fingerprinting. Science. 1997;278:1312–1314. doi: 10.1126/science.278.5341.1312. - DOI
    1. Tanno KI, Willcox G. How fast was wild wheat domesticated? Science. 1886;2006:311. - PubMed
    1. Fuller DQ, Qin L, Zheng YF, Zhao ZJ, Chen XG, Hosoya LA, Sun GP. The domestication process and domestication rate in rice: spikelet bases from the Lower Yangtze. Science. 2009;323:1607–1610. doi: 10.1126/science.1166605. - DOI - PubMed
    1. Doebley JF, Gaut BS, Smith BD. The molecular genetics of crop domestication. Cell. 2006;127:1309–1321. doi: 10.1016/j.cell.2006.12.006. - DOI - PubMed

Publication types

MeSH terms

Substances

LinkOut - more resources