Population Genetic Diversity of Mastacembelus armatus in Guangdong Based on the Mitochondrial Cytb Sequence
To understand the genetic diversity of Mastacembelus armatus in Guangdong,we sequenced the mitochondrial Cytb genes of 193 individuals of M.armatus from six rivers(Xijiang River,Beijiang River,Dongjiang River,Jianjiang River,Moyang River,and Hanjiang River)in Guangdong.The base composition and genetic distance were analyzed by MEGA 6.0.The diversity of each population was analyzed by DNAsp 5.0 and the haplotype network was established in Network 5.The results showed that the Cytb sequence of M.armatus was 1 138 bp in length.The Cytb sequences of 193 individuals showed the A,C,T and G content of 25.9%,32.7%,27.7%,and 13.6%,respectively.The genetic distance was 0.000 2-0.013 1,and the genetic differentiation coefficient was 0.035-0.866.A total of 38 nucleotide variation sites and 20 haplotypes were identified in the six populations of M.armatus,with the nucleotide diversity of 0.007 2 and the haplotype diversity of 0.782.The neighbor-joining tree established based on mitochondrial Cytb sequence showed that the populations of M.armatus in Guangdong were clustered into two clades:I and II.Clade I contained some individuals from Xijiang River,Beijiang River,Jianjiang River,and Moyang River and all the individuals from Dongjiang River and Hanjiang River.Clade II contained some individuals from Xijiang River,Beijiang River,Jianjiang River,and Moyang River.The haplotype network showed that the population in Xijiang River was closely related to those in Dongjiang River,Hanjiang River,and Moyang River,while the population in Beijiang River was distant from those in Dongjiang River and Xijiang River.The AMOVA results showed that 77.09%and 37.92%of the variations occurred between and within populations,respectively.The results of nucleotide mismatch analysis and neutrality test showed that there was no significant expansion of M.armatus populations in Guangdong.The M.armatus populations in Guangdong demonstrated low genetic diversity.Moreover,the genetic diversity of wild populations showed a decreasing trend.
NETL
NSTL
万方数据
维普
