Abstract:
We analyzed the genetic diversity on Periplaneta americana of 12 populations consisting of 360 individuals with 16 high polymorphic markers. The results showed that the number of alleles per locus ranged from 16 to 32, with an average value 24.5. The observed heterozygosity value (HObs) varied from 0.481 to 0.906 and the mean HObs was 0.698; the expected heterozygosity value (HExp) varied from 0.625 to 0.928 and the mean HExp was 0.840. The polymorphic information content (PIC) varied between 0.602 and 0.923. The analysis of Genepop and Popgene showed that a relatively high level of genetic diversity was revealed: the observed number of alleles was 10.0781; the effective number of alleles was 5.2746. The observed heterozygosity was 0.6882, and the expected heterozygosity was 0.7791, Nei's expected heterozygosity was 0.7661, Shannon's information index was 1.8056. Most loci were found to be deviated from HW test. A higher level of genetic diferentiation was detected among populations with mean Fst was 0.0891, the mean Nm was 2.5573, the genetic identity ranged from 0.4224 to 0.9405, the genetic distance ranged from 0.0613 to 0.8617. UPGMA cluster analysis indicated that the 12 populations were grouped into three major clusters, which showed that there had rich genetic diversity in P. americana, and the genetic diferentiation to some extent, the diferentiation in certain degree may result from geographical isolation and barriers to gene flow. These results would provide the basis of further study on genetic diversity and structure.
Keywords:
Polymorphism
,
Genetic diversity
,
Microsatellite markers
,
Periplaneta Americana