DNA Barcoding Research And Database Construction Of Smilacaceae

Smilacaceae is a cosmopolitan distribution and quite difficult taxonomically monocot family which includes2genera, Smilax and Heterosmilax, with about200species. In this study, we establish DNAbarcoding research and database construction of Smilacaceae based on barcording theory and method,20years worldwide research of the Smilacaceae of our lab, the history data of the word Smilacaceae taxonomy, molecular biology and computer network technology. We discuss the identified ability of DNA barcoding in the Smilacaceae, and evaluate the function and significance of DNA barcoding for revealing species boundaries. Through investigating the flora of all over the world, Smilacaceae specimens gained over the years, morphology, anatomy, pollen, chromosomes, molecular, biogeographic, ancient fossils and other research data of Smilacaceae, we establish database for promoting the management and sharing of information, and in-depth research. The main results are as follows:1. DNA barcoding research of SmilacaceaeDNA barcoding is a new molecular biology technique in which species identification was performed using DNA sequences from a small fragment of the genome. The realization of the automatic identification of species can overcome many defects of the traditional methods of taxonomic studies. So we choose plastid sequence such as rbcL, matK and nuclear ribosomal internal transcribed spacer (ITS) as barcode marker. Then we sample227individuals representing75species to assess the effectiveness and universality of these barcode markers in Smilacaceae. The results of barcoding gap test shows that rbcL, matK, ITS had not any large barcoding gaps. Wilcoxon signed rank testing was used to the difference between intra-and inter-specific. The result shows that ITS>>rbcL>>matK for inter-specific and ITS>>rbcL=matK for intra-specific. All the results of NJ, UPMGA, ML and MP analysis showed that single ITS has the highest recognition rate and are able to discriminate59.7%of species, while rbcL and matK are42.7%,36%, respectively. The recognition rate of the combination of rbcL+matK+ITS and rbcL+ITS can discriminate69.4%of species which were higher than each single fragment.According to the cost and efficiency, using rbch+ITS as the combination fragments to identify the species of Smilacaceae. Yet analysis the30%of the species that can not be identified in our study, and there may be two reasons:one is that Smilacaceae is a complex group, which is not fully differentiation; another one is possible to species identified error which is analyzed in this paper.2. Database construction of SmilacaceaeOn the basis of previous studies, we constructed a database of the cosmopolitan family Smilacaceae in this study. It is the first database about the single genus of the single family in China. The structure of the database is relationship data structure. The total data is about50GB. The content of the Smilacaceae database contains the overview, fossils, morphology, anatomical features, charecters of chromosome, pollen, fruits and seeds, DNA molecule data, genomic characteristics, chemical composition, and literature. The database also includes generic name, synonym, aliases, geographic distribution, height above sea level, habitat, morphological characteristics, seed morphology, testa micro-structure, chromosome karyotype, specimens pictures, live plants pictures and DNA molecular data.The platform of the Chinese-English website is developed by TOPRAND Co., Ltd. The function of the website includes:keyword search, visits statistical and back-stage management. It has the advantages of easy access, clear information structure, simple operation, easy routine maintenance, which can promote the exchange, share of the research, and lay the foundation for the further exploration of Smilacaceae.