Research Of Genetic Differentiation Of Geographical Population Of Macrotermes Barneyi Based On Mitochondrial CO?/CO? And Resequencing SNP

Macrotermes barneyi(Termitidae: Macrotermitinae: Macrotermes) is a kind of soil fungus-growing termite, which build their nests in the underground soil and collect litter and fiber cultivating fungus for food. The fungus-growing termite M. barneyi is an important species in the forest ecosystem,which can accelerate the cycling speed of wood fiber. However, when the species appear in human-made environment, they also do some harm to agriculture and forestry, water conservancy, buildings, transportation facilities,telecommunications equipment, timber trade, and so on. The fungus-growing termite M.barneyi is an important object of termite prevention and control in Asia, especially in China.The fungus-growing termite M. barneyi origin where and so far between geographical populations around the presence or absence of genetic differentiation is not yet clear. The paper intends to study the genetic differentiation of their geographical populations, exporing the origin of the species and the center of evolution and diffusion paths and ways to evolve, which can provide a theoretical basis for their use and prevention and cure.With the development of molecular biology and information science, the research of the fungus-growing termite M. barneyi has changed from the early morphology to the genetic level. Based on morphological identification,using mitochondrial COI /COII gene and resequecing technology(SNP) for the analysis of the fungus-growing termite M.barneyi specimens collected from 25 cities in nine southern provinces. The specimens were indentified by sequencing, phylogenetic analysis and genetic diversity analysis. The genetic evolutionary relationships of different geographical populations of the fungus-growing termite M. barneyi were studied. The results showed that:1.The fungus-growing termite M. barneyi COI gene sequences of AT composition(59.5%) were higher than CG composition(40.5%), COII gene sequences AT composition(64.6%) were significantly higher than CG composition(35.4%), and COII gene mutation area was larger than COI gene.2.Genetic distance of the fungus-growing termite M. barneyi mitochondrial CO?/CO? gene of different geographic populations between 0.002 to 0.005 and 0.002 to0.024.3.Based on genetic variation analysis of CO?/CO?/SNP found that the genetic variation existed in different provinces and regions of the fungus-growing termite M.barneyi, the same province in different areas and different collections sites in the same area of the fungus-growing termite M. barneyi also existed certain genetic variation.4.Based on the SNP genetic variation analysis:the phylogenetic relationship ofHainan,Yunnan,Guizhou specimens were more closer, and the phylogenetic relationship of Guangxi, Guangdong, Hunan, Jiangxi, Zhejiang, Fujian specimens were more closer.The mitochondrial genetic differences in the results were due to the geographical isolation and different geographical populations constantly adapted to different ecological environment and evolutionary arising from its existence genetic variation complex.5.The center of origin of the global Macrotermes was Africa.With the motion of the earth plate, Macrotermes diffused into Southeast Asia and Australia area.Macrotermes invaded China passing through the Peninsular Malaysia and other Southeast Asian countries,and then evolved into M. barneyi. Molecular evidence and phylogeographic analysis showed that Guangdong, Guangxi and Hainan was the developmental center of origin of M. barneyi. Then, M. barneyi gradually formed a branch to Yunnan, Guizhou development, and another branch was to Guangxi, Guangdong, Hunan, Jiangxi, Zhejiang,Jiangsu development, forming the northern line of M. barneyi distribution and whole world M. barneyi distribution.6.Different geographical populations of M. barneyi were only relatively independent, but they presented mosaic, overlapping relationship, and there was no clear separation among them. The relationship was relatively separation among them if the geographical barrier presented obviously. The mosaic, overlapping relationship was obvious if there was no geographical barrier.