Development Of Molecular Markers And Application On Genetic Diversity Study In Betula Luminifera

Special molecular markers were developed for Betula luminifera using Birch ESTs (Expression sequence tags) data. We then used these markers to evaluate the genetic diversity of B.luminifera germplasm. Based on their genetic distance, B.luminifera core germplasm was constructed. The main conclusions were as follows:1.Based on birch EST data, primers for 109 ACGM candidate loci were developed and tested in birch. Of these, 105 yielded single, stable and clear PCR products. We then tested the utility of those 105 markers in B. luminifera. The results showed 95 yielded stable and clear PCR products for at least one B. luminifera genotype of Lin'an 5 and Sichuan 4.2. Based on birch EST data, primers for 80 EST-SSR candidate loci were developed and tested in birch. Of these, 59 yielded single, stable and clear PCR products.We then tested the utility of those 59 markers in B.luminifera. The results showed 28 yielded stable and clear PCR products for at least one B.luminifera genotype of Lin'an 5 and Sichuan 4.3. The genetic diversity of 62 samples from B. luminifera germplasm was evaluated using ACGM markers. Nei gene diversity index and percentage of polymorphic loci of the samples were calculated, the values are 0.2138 and 54.74%, respectively. The observed number of alleles, effective number of alleles, Nei gene diversity index and percentage of polymorphic loci in Anhui (pop9) are the lowest, values are 1.1022, 0.0423, 1.0723 and 10.22%, respectively; whereas the highest in Linan (pop1), values are 1.4307, 1.3125, 0.1741 and 43.07%, respectively.4. The genetic diversity of 62 B.luminifera germplasm resources, representing 519 samples, was evaluated using ACGM markers. Of these 62 samples, 36 were selected as core collection. Results of t-test showed that the observed number of alleles, effective number of alleles, Nei gene diversity and Shannon information index of core collection had no significant differences with initial germplasm on 0.01 level. These results demonstrated that the core collection can represent initial germplasm resources.