Population Differentiation And Genetic Diversity Of Chinese Marsh Tits Based On COI And Microsatellites

The Marsh Tit(Poecile palustris) belongs to Paridae, Passeriformes, Aves. Poecile palustris is the typical smaller insectivorous bird species, it is widely distributed and very common in China, which is a good model for studies of population genetics and biodiversity and conservation.Genetic diversity has always been a hot topic in biodiversity research, and it is the basis for the species diversity to further understand the development and maintenance of the species. We used COI gene and microsatellite markers as tool to analyze population divergence and genetic diversity of Poecile palustris in China.In this paper,62 Poecile palustris were collected from Shangzhi of Heilongjiang Prov., Zuojia of Jilin Prov., Kuandian of Liaoning Prov., Shennongjia of Hubei Prov., Moerdaoga of Inner Menggolia, Lishan of Shenxi Prov,Foping,Taibai Shan and Yanan of Shaanxi Prov. and Mongolia. COI gene we sequenced contained 1201bp,90 variable sites which occupies 8.1%of the total. The A+T content (49%) of COI gene sequence was slightly lower than G+C content (51%), the tiny differences was matched to the features of avian mitochondrial DNA nucleotide composition. According to the substitution saturation analysis, nucleotide substitution was not reach saturation. There were 30 haplotype of all COI gene from 62 samples, haplotypes diversity (Hd) reached 0.933, the average diversity of nucleotides (π) was 0.0128. The species appeared with high haplotype diversity and low nucleotides diversity, which means the middium level genetic diversity.According to the phylogenetic trees built by Maximum Likelihood and Bayesian methods7the species was differentiated into several clades:species from Zuojia,Kuandian and Mongolia formed a clade; Yunnan was a separate clade; Foping, Taibai Shan and Yanan formed a clade; Taibai region and Lishan formed a small clade; Shennongjia and Foping formed another clade.Genetic diversity of Poecile palustris in China was analyzed by 9 pairs of microsatellite markers. We detected 74 alleles, the number of alleles ranged from 3 to 20. The average number of alleles observed microsatellite loci was 8.222, average effective number of alleles was 1.880, average observed heterozygosity was 0.331, average expected heterozygosity was 0.371, polymorphic information content PIC was ranged from 0.085to 0.886. Among the detection site, most of the genotype were deviate the Hardy-Weinherg equilibrium.In conclusion, this research used microsatellite and mitochondrial COI gene sequences as molecular markers to analyze population divergence and genetic diversity of Poecile palustris in China, which will benefit for the further phylogeographical studies. The species has been high diverged with middle level of genetic diversity, however the decresed population aboundance suggested its importance of conservation.