Abstract：In order to study the feasibility of DNA bar-coding technology in fish identification from the South China Sea, 65 species belonging to 43 genera, 28 families and 6 orders in the South China sea were collected and the COⅠ gene sequence of the species were amplified and determined, all sequences were aligned using BLAST from NCBI database for the species identification combining with the morphological information to identify and classify fishes. The sequence information, genetic distance and molecular phylogenetic tree of each species were calculated uing MEGA5.0 software. The results showed that the homologous sequence of COⅠ gene of 65 species were 633 bp. Comparing with the NCBI database, BLAST results with similarity rates of more than 99% can be obtained, which could be identified to species level. The average composition of A, T, G, C were 23.8%, 28.6%, 18.8% and 28.8%. The genetic distances among species, genera, families and orders were 14.88%, 19.09%, 23.14% and 24.68%, respectively. With the increasing of taxonomic category, the difference of average genetic distance became larger. In the phylogenetic tree, the species taxonomic relationships below family level were consistent with the morphological classification, while the relationships above family level were quite different from the morphological classification, indicated that the COⅠ gene is an effective bar code gene in fish molecular identification, but it is not necessarily suitable for the higher taxonomic level analysis for the molecular phylogenetic studies.
2020, Vol. 33 
