Using Aflp Marker To Analyze Genetic Resources Of Quercus Variabilis

Quercus variabilis is endemic, widespread in China that has an extremely essential species in forest with huge economic and ecological value. There are plentiful resources for oriental oak, but human disturbance and destruction of habitats have led to the secondary forests of the only existing. The study on genetic resources of Q. variabilis by genetic marker was not only helpful to investigate and evaluate germplasm resources scientifically on the basis of molecular level, but also guided to excellent genetic resources collection, conservation and formulate effective protection strategies. Facing the problem of inefficient oriental oak resources utilization and underdevelopment, the research on markers linked to the loci of phenotype by using molecular marker technologies for the sake of seeking linkage marker which can be applied to genetic research and breeding.1. The objective of the paper was to establish an AFLP reaction system fitting for Q. variabilis. The results indicated that the extraction of the genomic DNA should choose the improved CTAB method from the tender leaves of Q. variabilis. One-step method,200ng DNA dosage and digestion and ligation4hours were the best combination for the endonuclease digestion-ligation reaction system The preamplification reaction was carried out using20diluted digestion and ligation products. And the selective amplification was conducted with no diluted preamplification products immediately.2. Based on the AFLP reation system already established fitting for Q. variabilis, the paper analyzed the genetic diversity of the natural population and in half-sib population of ’plus’tree. The bands were rich and well polymorphism amplified by four pairs of AFLP primer combination. The results demonstrated that the genetic diversity of the natural population and’plus’tree offspring were all high. And high coefficient of genetic similarity in every population reflected a relatively close genetic relationship intra-population. As for natural population, the polymorphic fragment ratio was73.04%, Effective number of alleles was1.3961, Nei’s gene diversity was0.2388, and Shannon’s information index was0.3619. In regard to’plus’tree progenies, the polymorphic fragment ratio was84.07%, Effective number of alleles was1.4339, Nei’s gene diversity was0.2573, and Shannon’s information index was0.3924.3. Marker linked to the loci associated with phenotype in Q. variabilis was revealed by molecular marker technology with bulk sergeant analysis (BSA).3AFLP markers that amplified by E-AGG/M-CAA were identified which maybe related to the characters of cork thickness and thinness in natural population. The conclusion needed further screening, verification and application.