Genetic Diversity Analysis Of Sunflower Gerplasm Resourses By Using SSR Marker And Comparison Study On Four Oilseed Sunflower Hybrid

In China, sunflower resources are very rich, these enriched resources provide prosperous assets for the genetic improvement and the new speicies breeding of sunflowers. However,due to the limitation of research techniques and facilities, a comprehensive and thorough understanding about the sunflower germplasm resources is still lacking. Furthermore,the backgrounds of most sunflower germplasms in China have been far from being evaluated. In order to investigate and take full advantages of these germplasms, an efficient approach in the analyses and evaluations of these germplasms is critical. Nevertheless, in recent years, the sunflower varieties which have been applied on the agricultural production in China are mixed and became degraded seriously, exhibiting not only poor resistances to diseases but also low yield and quality. Therefore, selections of suitable sunflower varieties that show high adaptabilities to different ecological conditions are crucially important, allowing potential improvement of yield and quality.In this study, 132 sunflower varieties were taken as the experimental materials to analyze their genetic diversities and relationships at the molecular level using SSR molecular markers. Additionally, a comparative study was conducted on four oil sunflower varieties in the field of Sanyuan county, offering plausible therotical basises for the effienct use of these variety resources. The main results are summarized as the followingss:1.A modified CTAB method was successfully used in the extraction of sunflower genomic DNA. As a result, it was indicated that DNA with high quality could be made from tender leaves by this modified CTAB method.2. The results showed that the 22 pairs of polymorphic SSR primers were used to analyze the genetic diversity relationships of the 132 sunflower resources. A total of 153 allelic loci were amplified and on average, every pair resulted in 7 allelic loci. The polymorphic frequency for these loci was between 50%~100%.3. A genetic map of sunflower germplasm resources was obtained through a cluster analysis by assorting the SSR data after plotting in the NTSYS-pc2.10 e software. The genetic diversities and relationships of the variaties were further examined. In conclusion, the 132 sunflower variaties were classfied into five categories and germplasms with similar genetic backgrounds were grouped together. The result showed that use of SSR markers in distinguishing sunflower germplasms was feasible, and thereby may be an effective method in the investigations of genetic diversities within sunflower germplasm resources.4. In the variety comparative test, the four oilseed sunflower hybrid are growing orderly and strongly, Good resistance to lodging. According to the results of the main agronomic trait and economic trait showed that Sunflower yield is composed of multiple traits comprehensive decision.5. In the variety comparative test, the Oilseed sunflower hybrid the highest yield is 2013 hybrid NK175, 229.85 kg per a unit of area. NK244、NK175、XN1616、Nei kui za 2 are growing Strongly. According to the results of the main agronomic trait and economic trait showed that 2013 hybrid NK175 is the most suitable for planting in sanyuan region and the surrounding areas of Weibei.