| Abies fanjingshanensis (W.L.Huang.Y.L.Tu et S.Z.Fang) located at the top of the Mountain with a narrow distribution regions in the areas of Baiyun temple,Lanchading and Juchishan,in Guizhou's Fanjing Mountain .In 1981 , Abies fanjingshanensis was first discovered by W.L.Huang in Guizhou. Abies fanjingshanensis belong to Pinaceae fir species and were included in the China Plant Red Data Book,at the national level for the protection of plants,endemic plant in Guizhou Province. In 1998,IUCN developed the "conifer action plan",Abies fanjingshanensis was included in the global focus on the protection of conifer species.As the remnants of relict plant during Quaternary glaciers,Abies fanjingshanensis was very important for studying the flora of science,plant geography,paleontology,climatology and ancient glaciers.In this research,SSR and cpSSR were used to study genetic diversity and the effect of bottlenecks for 130 mature trees and 21 seedling trees of Abies fanjingshanensis population. Through this research,the genetic diversity and the extent of the bottleneck effect of Abies fanjingshanensis were revealed , so as to provide effective protection of Abies fanjingshanensis. The results of this study were the following:Firstly.SSR molecular markers reveal the level of genetic diversity of Abies fanjingshanensis: The average number of alleles observed (Na)is: 3.5 (mature tree),3.375 (seedling).the average effective allele for the tree( Ne) is: 2.5594 (mature tree),2.2944 (Seedling),observed heterozygosity (Ho) is 0.4904 (mature tree),0.4107 (seedling),expected heterozygosity (He) is 0.5505 (mature tree),0.5078 (seedling). SSR reveals Abies fanjingshanensis mature trees have more genetic diversity than seedling trees ,and expected heterozygosity were higher than those observed heterozygosity.Secondly.The allele frequencies for the seven-point polymorphism and Inbreeding coefficient for polymorphic loci in mature trees and seedling trees of Abies fanjingshanensis were estimated .The average Fis is 0.113 for mature trees,range from -0.064 to 0.278; The average Fis is 0.215 for seedling trees,range from -0.077 to 0.459. Fis are greater than zero for mature trees and seedling trees.It is possible that inbreeding might have occurred in Abies fanjingshanensis population and seedlings trees of Fis was significantly larger than the mature trees.Thirdly. CpSSR method of the six polymorphisms fragments in all individual of Abies fanjingshanensis reveal eight kinds of different haplotypes. The number of effective haplotypes (Ne)is 4.6148,haplotype heterozygosity (He) is 0.7886. Various haplotypes difference between the frequency of relatively large,including B-type haplotype was accounted for 41.05 percent,C,E,H-haplotype which accounted for 6.62 percent,1.32 percent and 0.66 percent, It is said that C,E ,H-haplotypes in Abies fanjingshanensis were very scarce.Fourth. Mutation model based on the two-phase (TPM,Two-phase Mutation Model) of the Abies fanjingshanensis tree heterozygosity excessive testing showed that the expected heterozygosity(He)was significantly larger than the average heterozygosity (Heq ,P value of 0.052 to 0.294) . Heterozygosity excessive WILCOXON one-tail test (P = 0.00391) of Abies fanjingshanensis shows that serious genetic bottleneck haved occured. The test of Allele frequency mode shift showed that the populations of the Abies fanjingshanensis allele frequency deviation from the normal distribution of L-shaped that Abies fanjingshanensis in the past have experienced a serious bottleneck effect.According to the result of this study: Abies fanjingshanensis population has undergone genetic bottleneck effect,and the phenomenon of inbreeding within populations,low genetic diversity. Therefore,the proposal should make great efforts to protect the habitat around Abies fanjingshanensis and every individual,at the same time we should strengthen the study of survival for Abies fanjingshanensis.
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