The Research On Genetic Diversity Of Davidiainvolucrate In The Western Of Hunan And Hubei Province By Random Amplified Polymorphic DNA (RAPD)

Dove tree (Davidia involucrate), specially distributing in China, is relic plant species from tertiary palate-tropical, and belongs to Davidia and Nyssaceae. It is famous as an epibiotic origin woody ornamentais and has been presently listed as first class of protective rare and endangered plant in China.The polymorphic RAPD molecular markers exist in nature population of Dove tree was identified, the genetic structure and the level of gene flow of natural population was studied, and the inbreeding coefficient and other genetic parameters was estimated using RAPD in this paper.The research results are as follows:(1) The sample DNA were distilled using 2×CTAB, and the optimum reaction condition of RAPD for Dove tree leaf were found.(2)9 primers that can produce polymorphic, clear and bright bands, sound repeatability have been selected for RAPD amplification and analysis on DNA samples in the western of Hunan and the western of Hubei nature population from 40 random primers.(3)Totally 27 polymorphic markers were obtained by amplifing on 60 samples using 9 selected polymorphic primers, and3polymorphic loci had been yielded in each primer, averagely. The percentage rate of polymorphic loci in the population form the western of Hunan is higher than the western of HubeiHubei.(4) There was not found different between the genetic diversity of natural populations from the western of Hunan and the western of Hubei. The Shannon information indexs of these two populations are 0.4274 and 0.4481 respectively. The average genetic diversity is 0.3269,0.2976 and 0.0308 within species, within population and between two populations, respectively. The coefficient of genetic differentiation and gene flow between two populations are 0.0896 and 5.0792, respectively. The genetic identity and genetic distance between two populations was 0.9233 and 0.0798, respectively. It is indicated that most of genetic variation in Dove tree existed within the population, and the gene flow between two natural populations was very frequently.