关键词: 黑胸大蠊, COI基因, 遗传多样性, 系统发育地理结构

Abstract: To investigate genetic diversity and phylogeographic structure of Periplaneta fuliginosa in some parts of China, this study applied PCR amplification and sequencing methods to determine a 658 bp fragment of partial COI gene sequences of 88 P. fuliginosa samples from 9 geographic populations. The genetic diversity, genetic differentiation, gene flow and phylogeographic structure were analyzed. The results showed that 11 variable sites and 7 haplotypes (Hap1-Hap7) were detected among all COI sequences of 9 P. fuliginosa geographic populations. Among 7 haplotypes, the haplotype Hap3 was shared by all the 9 populations. The total haplotype diversity (Hd) and nucleotide diversity (Pi) of all populations were 0.327 and 0.0017, respectively. The neutrality test Tajima′s D was -1.2743, indicating no sign of population expansion in recent history. The total Gst was 0.1060. The Nm was 4.22, showing evidence for extensive gene flow among populations. The phylogenetic tree and haplotype network analyses showed that haplotypes from different geographical regions did not cluster together and separate each region from other regions. The molecular variance analysis (AMOVA) demonstrated that genetic differentiation mainly occurred within populations, and there was no significant genetic differentiation among populations. Furthermore, a Mantel test detected no obvious correlation (R=0.0038，P=0.5670) between genetic distance and geographic distance among P. fuliginosa populations. The results indicated that genetic diversity of P. fuliginosa was relatively low and there was no phylogeographic structuring among P. fuliginosa populations.

Key words: Periplaneta fuliginosa, COI gene, genetic diversity, phylogeographic structure