| Taxus chinensis var. mairei, being one of the state-protected one-grade rare and endangered plants, is one of the tertiary relic species an endemic to China. Fujian is the boundary of its distribution. Areas where Taxus chinensis var. mairei is distributed in Fujian are centralized and the resources are abundant. This paper describes the analysis of genetic diversity among Taxus chinensis var. mairei distributed in 23 different provenances in Fujian as revealed by RAPD molecular marker and ISSR molecular marker, The main results obtained are as follows:1. Extracting plant total DNA was tested with Biospin plant genomic DNA extraction kit, results high purity and integrity of DNA sample, the advantages and disadvantages of the Biospin plant genomic DNA extraction kit and other methods were compared when used for genomic DNA extraction, order to establish a simple and feasible measure to extracting plant total DNA.2. Abstract Genomic DNAs was used as template to optimize the random amplified polymorphic DNA(RAPD)reaction system and the inter simple sequence repeat (ISSR) reaction system, some essential factors which might take effects on the results of marker were investigated, optimized the PCR amplification technology system and final established the optimum reaction conditions. We refer to the PCR reaction system which had been stable in Taxus chinensis var. mairei into the system in the primer screening research, and then the system was tested and improved more and more.3.The genetic diversity of 23 provenances were evaluated by RAPD marker, thirteen primers were used and 147 bands were produced,of which 136 were polymorphic,and each primer generated 11.3 polymorphic bands. The Shannon's Information index was 0.1821~0.3296 with 0.2134 on average,which showed rich genetic diversity of Taxus chinensis var. mairei. 23 provenances could be divided into 4 main groups by cluster analysis on the genetic characteristics. But, it couldn't indicating the geographical distribution of genetic diversity of Taxus chinensis var. mairei. The research suggested RAPD was a useful marker system for primary or ordinary genetic research.4. The genetic diversity among 23 provenances was tested by ISSR marker. A total of 145 bands were amplified by twelve ISSR primers,among which 140 (96.55%) bands were found to be polymorphic. The percentage polymorphic band was higher than other species by ISSR marker. Each primer generated 12.1 polymorphic bands. Abundant genetic diversity among Taxus chinensis var. mairei could be revealed. Analysis of cluster and principal component showed that all the 23 provenances could be distinguished by ISSR markers and divided into 4 groups, indicating the better geographical distribution rule of genetic diversity than RAPD. The result showed that ISSR marker fit not only the genetic diversity research but also the cultivar identification according to exact and simple operation for any species.5. The more efficient measures must be taken for the collection and protection of Taxus chinensis var. mairei according to the rich genetic diversity. Being as the major distribution area and total production base of China, Taxus chinensis var. mairei resources have been severely destroyed in Fujian. the existing issues that constrained Taxus chinensis var. mairei resources protection and sustainable and industrialize development in Fujian, and put forward the corresponding strategies with the protection of genetic diversity should be paid much attention, frequent gene flows among populations should be enhanced.According to its study of genetic diversity among Taxus chinensis var. mairei, it had significantly utilization in forest genetics. This paper researched basically Taxus chinensis var. mairei, and provide basic study for the further study.
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