天然珙桐群体的RAPD标记遗传多样性研究

利用RAPD技术 ,通过 13个引物对 5个天然珙桐种群的遗传多样性、种群内和种群间的遗传变异进行了研究。结果表明 :珙桐天然种群具有丰富的遗传多样性 ,但群体间的差异明显 ,2 6 %的遗传变异存在于群体间 ,与我国濒危树种马褂木和银杉等相似 ,而与广布性树种相异。取样方法对遗传多样性参数的影响分析表明 ,有效等位基因数和基因多样度受取样个体数的影响较小 ,群体间的分化系数和基因流的估算受取样个体数的影响较大。研究还将珙桐划分为东南部和西北部两大种源区。通过珙桐遗传多样性的研究 ,为今后有效保存和合理利用珙桐种质资源提供了理论依据

Study on Genetic Diversity of RAPD Mark for Natural Davidia involucrata Population

Davidia involucrata which belongs to Nyssaceae section monotype genus is peculiar plant in China, being old origin and survivor of tropical flora of Tertiary Period, it is classified as the first-grade state protection plant. The genetic diversity and genetic variation within populations and inter-populations from 5 D. involucrata natural populations by 13 primers have been studied based on RAPD analysis. The results showed that D. involucrata natural population had rich genetic diversity, but the difference was significant among the populations, and 26% of genetic variation existed among the populations, which was similar to endangered tree species of Liriodendron chinense and Cathaya argyrophylla in our country, but different from widely-distributed tree species. The result of the sampling method impacting on genetic diversity parameters showed that: effective number of alleles and genetic diversity took sample number influence relatively light, and genetic differentiation among the populations and gene flow took sample number influence relatively heavy. The study divided D. involucrata into 2 big provenance plots of southeast and northwest. The study on genetic diversity of D. involucrata will provide theory basis for developing studies on effective conservation and reasonable utilization of germ plasm resource from D. involucrata in the future.