RESUMO
Objective: To obtain the structural characteristics of chloroplast genome in Psammosilene tunicoides and analyze its phylogenetic position within the family of Caryophyllaceae. Methods: High-through-put sequencing technology and bioinformatic analysis softwares were used to analyze the structures of complete chloroplast genome of P. tunicoides. RAxML 8.2.11 software was utilized to reconstruct the Caryophyllaceae phylogentic tree with Amaranthus hypochondriacus as outgroup. Results: The complete chloroplast genome was 153 977 base pairs (bp) in size, including two inverted repeat (IR, 26 033 bp) regions separated by one large singe copy region (LSC, 84 385 bp) and one small singe copy region (SSC, 17 526 bp). The genome encoded 125 genes, of which 109 were unique, including 75 protein-coding genes (PCGs), 30 tRNA genes and 4 rRNA genes. The overall GC content of P. tunicoides was 36.5%, while those of IR regions (42.4%) were higher than LSC (34.2%) and SSC (30.1%) regions. The phylogenetic tree showed that P. tunicoides and Dianthus longicalyx were sister groups with 100% bootstrap value. All nodes of the phylogenetic tree of Caryophyllaceae were of high supports, and the ML tree had good resolution to reflect the phylogeny relationship among the Caryophyllaceae. Conclusion: The complete chloroplast genome of P. tunicoides and the phylogenetic relationship within Caryophyllaceae were analyzed in this study. The results will provide effective molecular information for further studies on evaluation of germplasm and molecular phylogeny of Caryophyllaceae.
RESUMO
Psammosilene tunicoides is one of the main ingredients of the "Yunnan Baiyao". P. tunicoides is an endangered species included in the secondary protection list in China Plant Red Data Book as well as the endemic species in Southwest China. Its natural resources could not meet the needs of pharmaceutical production. Construction of core collection of P. tunicoides will lay the foundation for germplasm improvement and molecular breeding. The sequence variation of the key enzymes gene locus (β-AS) were carried out to survey the population structure and population history of the species. Among the 11 populations across its geographical range, 36 haplotypes were identified. The levels of haplotype diversity (Hd=0.905) were high, while the levels of population differentiation (GST=0.280) were low. Analysisof molecular variance (AMOVA) indicated that a significantly greater proportion of total genetic variationpartitioned among populations thanwithin populations (values of 77.43% and 22.57%, respectively). These results in combination with the star-like phylogenetic network analysis indicate that Hap1 as an ancestral haplotypewas shared in four populations, Hap2, Hap4, Hap15 and Hap16 are occurred in two populations, the remains as private haplotype only distributed in single population. The strategy of core collection was constructed in order to maximumpreserve genetic diversity of P. tunicoides.