| Tea plant (Camellia sinensis (L.) O. Kuntze) is one of the important economic plants in China, which has long planting history and being distributed widely. Research findings proved that southwestern part of China is the original center of tea plant, teemed with germplasm resource of tea plant. Currently, China has set up two germplasm resource gardens of tea plant, where 3300 species are collected, and increasing by 100 species every year. Such rich resources are fundamental material for cultivars innovation and biotechnology research, and of important value and potential either in the past, present or in the future. Genetic breeding, based on genetic diversity of germplasms, will be improved by establishing core collection—a method which make more efficient use of present germplasms. Random amplified polymorphic DNA (RAPD), A newly developed molecular marker techniques, is a powerful method for studying bio-diversity and establishing core collection. It has been popularized for its rapidity, simplicity and revealing the genetic diversity on DNA level.Two parts were included in this paper. First, the pre-core collection of Camellia Sinensis in China was established and evaluated in its representation. Camellia Sinensis germplasms in China were divided into 18 groups according to their origin,tree shape and variety type. In each group, numbers of entries were decided based on sampling strategies combined stratification with random and cluster analysis by Ward's methods. A pre-core collection comprised 126 accessions from 615 Chinese tea plants in the whole collections. Through the T-test of Shannon diversity index there is no difference between both. After the compare of ten agronomic traits-tree pose,leaf shape,leaf color,leaf cover,leaf apex,bud-leaf floss,ovary floss,weight of 100 buts,amount of floral leaf and amount of floral pillar fission, six eigenvalues-max,min,range,mean,SD and CV are close between the pre-core collection and the whole collection. Their mean and SD is 97.08% and 95.51% partly. The results show the pre-core collection can well represent the genetic diversity of the whole collection. Secondly, the genetic diversity of the pre-core collection of Camellia Sinensis was detected by RAPD analysis.This study was to evaluate the genetic diversity of 69 tea cultivars of the preconcentrated core germplasms of Camellia Sinensis in China by the random amplified polymorphic DNA(RAPD).Among 50 arbitrary primers, 32 primers could get enough amplified bands for all the strains. Among a total of 348 bands observed, 328(94.3%)bands were ploymorphic in the 69 cultivars tested, only 20 ones did not reveal ploymorphic. Genetic distances between the cultivars varied from 0.223 to 0.723. This study indicated genetic structure and genetic diversity and genetic distance of the pre-concentrated core germplasms of Camellia Sinensis in China could well represent the whole collection. At the same time, DNA molecular markers are simple and intuitionist, but expensive comparing to morphological markers. They discover the heredity and differentiation of total genome among cultivars. But morphological markers discover the heredity and differentiation, which control some morphological group. It was the best option to establish core collection of Camellia Sinensis in China binding morphological markers with DNA molecular markers.
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