| Based on the investigation of the primrose(Primula L.)germplasm resource in the western areas of Sichuan province,the genetic diversity and the phylogenetic relatives of different species was analyzed by using RAPD and AFLP makers. And the effect of influence factors (such as the different habitat and geographical barrier) on genetic variation and evolvement of Primula was discussed. Then the theoretical science guideline and production were proposed to the resource conservation, core idioplasm construction of primrose genus, as well as its development and utilization.The main results were as follows.1. Based on the investigation of the primrose(Primula L.)germplasm resource,31 species primrose (Primula L.)germplasm resource, including 4 subspecies were divided into 11 groups in the western plateau of Sichuan province. Some species with higher ornamental value are worthy to exploited.2. By using RAPD maker, the results of 85 tested materials from 13 species of Primula indicated that 28 RPAD primers were amplified 250 DNA fragments, including 209 polymorphic fragments (83.6% in total) were detected. Therefore,173 DNA fragments were amplified from P. yargongens, including 82 polymorphic fragments (47.4% in total) were detected, 206 DNA fragments were amplified from P.alpicola, including 155 polymorphic fragments (75.2% in total) were detected,and 187 DNA fragments from P.chienii, 94 polymorphic fragments (50.3% in total).Meanwhile, 143 individuals of P.cockburniana were sampled and analyzed by using AFLP maker, which underlies selecting six primers combinations. 546 DNA fragments with 100-850bp were amplified,including 218 polymorphic fragments were detected.All of the results showed that the genetic diversity among the different species and in the same species of primrose was obvious.3. Based on the tagged results of RAPD, UPGMA cluster analysis was carried out,the genetic distance of 17 tested materials of P. yargongens was between 0.0345～0.9523,and the mean of genetic distance among the materials was 0.4584. Within the population, The mean of genetic distance of Mugecuo population was 0.6255, the mean of genetic distance of Kangding population was 0.2972 and that of Litang population was 0.2239, the mean of genetic distance of Mugecuo population and Kanding population was 0.5352, which indicated relatives between the two population was closer. In contrast, the mean of genetic distance of Kangding population and Litang population was 0.6134, which indicated more genetic difference and less relatives exists between the two population.The genetic differentiation among populations increased along with the increase of geographical distanceHowever, 143 individuals of P.cockburniana were tested by UPGMA cluster analysis based on single match coefficient(SM). The results indicated that genetic distance among populations was not obviously related to geographical distance. The genetic relationship was more close though distance of Mt. Zheduo to Danba Dangling was more than that of Mt. Zheduo to Yajiageng of Kangding. Accordingly, that of Danba Tiantanggu-dangling groups clusters into one category in singular.That of Mt. Zheduo clusters with that of Danba Tiantanggu-dangling.143 individuals from 10 populations were not clustered in the core of respective population. Intercross was very serious, which indicates that differentiation within population was apparent, differentiation level was different among populations, and genetic drift exists within the populations.4. The results of AFLP analysis showed that the total genetic diversity (Ht) of P.cockburniana population was 0.0961,and genetic diversity within the population was 0.0619. The coefficient of gene differentiation(Gst) in 10 populations was 0.3557. The results indicated that individual differentiation level was high within the population.All the genetic variation comes from individuals of population. Ht and Hs of that of Yajiageng of Kangding were higher than that of Danba Tiantanggu-dangling. The results was the same to that by AMOVA technique.As a while, Gene flow (Nm) among the 10 populations was 0.9056<1. Genes transferring was lack among the population. But Nm in Yajiageng of Kangding population was 1.3617>1, and 1.0554>1 in Danba Tiantanggu-dangling population. It shows that frequency of Genes transferring was highly existed in populations of group so that it is moderate5. The effects of different habitat and eco-geographic areas on genetic diversity of Primula were significant. Habitat with good condition was benefit to improve the genetic diversity of Primula. Gene flow with high quality and stability in the same district was benefit to the uniformity of Primula population. Individuals of Primula population in Longchi of western Sichuan were clustered together, and this was obviously different from that of Ganzi area.6. Cluster analysis based on RAPD marker was different from the category of morphological type. P. pulverulenta Duthie didn't cluster with P.bulleyana and P.secundiflora, which were belong to Sect. Proliferae, originated from the same group in category of morphology. The P.pulverulenta Duthie was clustered with materials that originated from the same district, Longchi. It indicated that the genetic structure of Primula was affected by the type of Eco-geography. Likewise, systematic positioning to P.secundiflora was studied. The result indicated that P.secundiflora was clustered with Sect. Proliferae. So, it showed that P.secundiflora was more close to Sect. Proliferae...
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