Construction of a genetic linkage map for Camellia sinensis (tea)

Abstract

Genetic maps are a vital tool in cultivar improvement programmes for woody perennial tree crops such as tea (Camellia sinensis). A population thought to be derived from two known, noninbred parents was scored for RAPD and AFLP markers, in order to develop a linkage map. However, a very high proportion of the markers exhibited unexpected segregation ratios in the light of their con®gurations in the parents, and an exploratory statistical analysis revealed patterns in the marker scores which can most easily be explained by the hypothesis of three male parents contributing pollen to this cross. We discuss the evidence for this and the subsequent analysis required to assemble the markers from the female parent into the ®rst linkage map for tea. The map has 15 linkage groups of three or more markers, agreeing with the haploid chromosome number of tea. The statistical methods that revealed the subpopulations are easy to apply routinely, and may prove a useful diagnostic tool for the analysis of noninbred mapping populations.

Development of CAPS markers based on three key genes of the phenylpropanoid pathway in Tea, Camellia sinensis (L.) O. Kuntze, and differentiation between assamica and sinensis varieties

“…A first genetic map of assamica tea has been published (Hackett et al 2000) and another one using a sinensis mapping population is in progress (Tanaka 2001). Both maps have been constructed using RAPD and AFLP markers.…”

The use of RAPD markers for detecting genetic diversity, relationship and molecular identification of Chinese elite tea genetic resources [Camellia sinensis (L.) O. Kuntze] preserved in a tea germplasm repository

“…More recently, it has also been used with tea plant for the investigation of genetic relationships (Wachira et al 1995;Lee et al 1995), identification of parentage (Tanaka and Yamaguchi 1996;Tanaka et al 2001), evaluation of DNA polymorphism (Kaundun et al 2000;Park et al 2002), detection of genetic stability (Chen et al 1999) and integrity (Mondal and Chand 2002), genetic linkage mapping (Hackett et al 2000), as well as reconstruction and assessment of the phylogeny of tea plant and its allied species in section Thea (Chen and Yamaguchi 2002) and genus Camellia (Wachira et al 1997). However, the genetic diversity, relationship and molecular identification of Chinese tea genetic resources using RAPD markers has hardly been reported yet.…”

Review on Tea (Camellia sinensis) Research Achievements, Challenges and Future Prospective Including Ethiopian Status

“…The first linkage map for tea plant was constructed with RAPD markers by Tanaka (1996), and the markers related with theanine content, date of bud sprouting, resistance to anthracnose and tolerance to cold were detected (Tanaka,1996). Another linkage map from the female parent, SFS150, was established with RAPD and AFLP markers (Hackett et al, 2000).…”