1.Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Science, Tianjin Normal University, Tianjin 300387,China; 2.Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380,China;3.Tianjin Tianxiang Fishery Company Limited,Tianjin 301500,China
Abstract: The PCR technology was used to amplify the mtDNA COⅠ region of 21 individuals of northern subspecies and 19 individuals of Florida subspecies of largemouth bassMicropterussalmoides, and about 1400 bp DNA fragments were obtained, in which the sequence of 1337 bp fragment were obtained by sequencing. Comparing with COⅠ region of mtDNA complete sequence of largemouth bass (GenBank:DQ536425),there were five base substitutions and the haplotype detected was only one within northern subspecies. There were five haplotypes within Florida subspecies, and the 41 bases substitution was detected in all individuals of Florida subspecies compare with northern subspecies. The six haplotypes has GenBank serial numbers from KF176376 to KF176381 and the base composition and base differences were calculated by Mega 4.0 software, with haplotype diversity index (H) of 0, nucleotide diversity index (Pi) of 0 and average nucleotide diversity (k) of 0 in northern subspecies. Florida subspecies hasHof 0.784,Piof 0.003 42 andkof 4.573. The two subspecies have average Kimura 2-parameter genetic distance of 0.035 1. There was higher genetic diversity in mtDNA COⅠ region in Florida subspecies than in northern subspecies, indicating that the sequence of mtDNA COⅠ region can be used as a DNA barcode for identification of the two subspecies of largemouth bass.