Genetic Diversity And Classification Research Of Japanese Marsh Warbler (Megulus Palustris Sinensis)

Japanese Marsh Warbler (Megalurus palustris ) is one of the species which only distributed in east Asia, the population number is very small, it has been listed by IUCN as endangered species, at present there are little researches on it and the mechanism of endanger is not very clear. As the evolution rate of control region of bird is faster and the genetic variation of this region is the most compared with other parts of mitochondrial DNA, this region is used in the research of genetic differentiation of inner species, interspecies, and interindividual. In this study, DNA sequence analysis was used to detect the genetic diversity level of Japanese Marsh Warbler. A part sequence of the mitochondrial control region (797 bp) was obtained in 30 great samples in the breeding sites of Zhalong, among them, 15 were obtained in 2004, and the other 15 were got in 2005. The results showed: 15 variable sites were found in 30 d-loop sequences, only one variance was transversion, the others were transitions, and two sits (224, 579) lost nucleotide A. In total, 14 haplotypes were detected in 30 samples, the frequency of Hapototype A was as high as 53.3%, Haplotype diversity Hd=0.772, Nucleotide diversity Pi=0.00139, Average number of pairwise nucleotide differences k=1.106, the difference of the haplotypes was not significant.The genetic diversity of Japanese Marsh Warbler in Zhalong is lower than Great reed warbler, which is widespread species and in the same subfamily with Japanese marsh warbler. The value of Fst between them is 0.03537, and the genetic divergency between group 1 (2004) and group 2(2005) is not significant.In traditional classification system, Japanese Marsh Warbler was classified to Megalurus genus, but there are another viewpoint that it should be considered to be classified to Locustella genus, this view was supported by morphological research and molecule systematics research. In this reseach, complete cytb of Japanese Marsh Warbler (1134bp) was Sequenced, and 835bp of 8 kinds of birds were usedto discuss the location of Japanese Marsh Warbler, and the phylogenetic relationship of Locustella genus. The result suggestd that: Japanese Marsh Warbler should be classified to Locustella genus.The distance data and treebuilding result both support that Pleske's Grasshopper-Warb (Locustella pleskei) and Rustyrumped Warbler (Locustella certhiola), River Warbler (Locustella fluviatilis) and Savis Warbler (Locustella luscinioides) has closer relationship than compared with others.