title: Development of SSR Markers and Assessment of Genetic Diversity in Medicinal Chrysanthemum morifolium Cultivars.
abstract: Chrysanthemum morifolium, is a well-known flowering plant worldwide, and has a high commercial, floricultural, and medicinal value. In this study, simple-sequence repeat (SSR) markers were generated from EST datasets and were applied to assess the genetic diversity among 32 cultivars. A total of 218 in silico SSR loci were identified from 7300 C. morifolium ESTs retrieved from GenBank. Of all SSR loci, 61.47% of them (134) were hexa-nucleotide repeats, followed by tri-nucleotide repeats (17.89%), di-nucleotide repeats (12.39%), tetra-nucleotide repeats (4.13%), and penta-nucleotide repeats (4.13%). In this study, 17 novel EST-SSR markers were verified. Along with 38 SSR markers reported previously, 55 C. morifolium SSR markers were selected for further genetic diversity analysis. PCR amplification of these EST-SSRs produced 1319 fragments, 1306 of which showed polymorphism. The average polymorphism information content of the SSR primer pairs was 0.972 (0.938-0.993), which showed high genetic diversity among C. morifolium cultivars. Based on SSR markers, 32 C. morifolium cultivars were separated into two main groups by partitioning of the clusters using the unweighted pair group method with arithmetic mean dendrogram, which was further supported by a principal coordinate analysis plot. Phylogenetic relationship among C. morifolium cultivars as revealed by SSR markers was highly consistent with the classification of medicinal C. morifolium populations according to their origin and ecological distribution. Our results demonstrated that SSR markers were highly reproducible and informative, and could be used to evaluate genetic diversity and relationships among medicinal C. morifolium cultivars.
authors.affiliation: Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, College of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China.
authors.forename: Shangguo
authors.initials: S
authors.lastname: Feng
authors.affiliation: Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, College of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China.
authors.forename: Renfeng
authors.initials: R
authors.lastname: He
authors.affiliation: Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, College of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China.
authors.forename: Jiangjie
authors.initials: J
authors.lastname: Lu
authors.affiliation: Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, College of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China.
authors.forename: Mengying
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences Hangzhou, China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Shen
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences Hangzhou, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences Hangzhou, China.
authors.forename: Zhi'an
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, College of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China.
authors.forename: Huizhong
authors.initials: H
authors.lastname: Wang
keywords: Chrysanthemum morifolium; EST-SSR; genetic diversity; marker development; phylogenetic relationship