Population genetics and pedigree geography of Trionychia japonica in the four mountains of Henan Province and the Taihang Mountains

Abstract

Abstract Objective Human activities and climate change have changed the living environment of species, accelerated the rate of species extinction, and global biodiversity is facing a huge threat. The objective of this study is to determine the resource protection strategy of freshwater planarian by systematically exploring the population genetics and pedigree geography of the planarian population in the four mountain systems of Henan Province and Taihang Mountains. Methods Taking the Japanese planarian in the four mountain systems of Henan Province and Taihang Mountains as an example, DNA was extracted with the help of mitochondrial cytochrome c oxidase subunit I gene (COI), mitochondrial cytochrome b gene (Cytb), and nuclear gene internal transcribed spacer-1 (ITS-1), amplified by polymerase chain reaction and sequenced, and genetic diversity, genetic structure, and pedigree geographical pattern were analyzed by single-gene analysis and polygene joint analysis. Results The corresponding length of Cytb, COI, and nuclear gene ITS-1 sequences in the four mountains of Henan Province is 308, 805, and 632 bp, respectively, and the nucleotide diversity and haplotype diversity are 0.00212 and 0.975, respectively. The gene length of ITS-1 and Cytb in Taihang Mountains is 668 and 315 bp, respectively, with a total length of 984 bp. There are 10 shared haplotypes and 36 unique haplotypes. The values of all nucleic acid diversity and haplotype diversity were 0.00156 and 0.965, respectively, and the genetic variation coefficients between populations and groups were 20.28% and 16.40%, respectively (P < 0.05). Different haplotypes of the four mountain systems in Henan Province and Taihang Mountains are scattered in different geographic populations, and there is no correlation between them and their geographic locations, which is consistent with the results of phylogeny. Conclusion The genetic diversity of Trionychia japonica population in the four mountain systems of Henan Province and Taihang Mountains shows high haploid diversity and low nucleotide diversity, and phylogenetic analysis has not found obvious pedigree geographical pattern.