| China is a growth sources that silkworm mulberry produce, with history that has more than 5000 years. Because the country plants the mulberry history long, add it the country the territory broad, ecosystem environment complicacy, for these reasons the categories are numerous. Selecting in different ecosystem environment and long-term natures to mulberry tree with the artificial, it becomes many kind of varieties, mutations and species. These are very precious germplasm resources in our country plant gene pool. But for long time, in plant classification in mulberry because of the different comprehension for the concepts of the species and variety, the difference of the primitive material, the traditional classification can not bring forward a system for everybody all accepting definition. As a result the species of the demarcation still has on a certain artificial degree . Moreover, because the mulberry is a cross-pollinated plant, it is hard to judge the relations among the species accurately because of the hard up for phylogenetic information in transition types formed in intra-species and inter-species hybridization, therefore, there is no satisfied classification method for Morns L.. In recent years the molecular biology technique that regards the nucleic acid analysis as the main contents developed the new path for from the DNA molecular level researching heredity innate characters, for plant evolution, systemic classification with identification and germplasm resources genetic diversity. The molecular biology leading into the phylogenetics and evolution research makes the systematic knowledge that disputed over a long period of time get the solution, making phylogenetics and evolution research take place the big transform. Therefore, making use of the molecular biology technique research phylogenetics and evolution of mulberry , it is beneficial to resolve the problems existing plant classification of Morus, and has very important meaning for analysis, identification and use of the germplasm resources, for mulberry breeding.In this thesis, several aspects of analysis research for 15 species and 4 varieties in current classification of mulberry were carried out by making use of the modern molecular biology analysis technique combination with calculator analysis software , including numerical value cladistic analysis, genetic diversity analysis, relations among cultivated species, constructing molecular phylogenetic tree and so on.These results provided the new data for the aspects of genetic structure relations, phylogenetic relations, development and use of germplasm resources in Morus species of China. The main contents and results summary are as follows :1. Cladistic analysis of mulberry (Morus L.)The appearance characteristic classification for mulberry (Mours L.) came from Linne's Species Plantarum(1753).He divided mulberry into 5 species, among them white mulberry (M.alba L.) originatedfrom China. To the current mulberry classification influence biggest is classification system that Koidzumi had built (1917,1923), which primarily based on flower organ.. According to the principle of cladistics analysis, 16 main appearance characteristics were proceeded the numeric value coding , getting the multi-state numeric value coding matrix. Analyses were carried by Maximum parsimony(MP) method, using the allied genus paper mulberry (Broussonetia papyriferd) as outgroup. The result manifested the biggest variety step of tree is 75 , consistency index (CI) is 0.36. There is a bigger difference between dendrogram of cladistics and traditional classification, that possibly relate to choice of characters in appearance classification. Appearance alike can not complete reflect the phylogenetic relationships. But also reflected to evolve the trend obviously in cladogram: M.alba L., M.multicaulis Perr. and M.atropurpurea Roxb. etal species are more evolutionary group, and M.notabillis Schneid lie down the base of cladogram is primitiver species in evolution. For further research of heredity fou...
|
PDF Full Text Request