Characterization of accessions of some Onobrychis species by flow cytometer and DNA markers (SSR)

The objectives of this master thesis are to determine nuclear DNA contents, and ploidy levels of 100 genotypes representing 44 accession from 18 different species (O. arenaria subsp. arenaria, O. inermis, O. petraea, O. cyri, O. iberica, O. altissima, O. vassilczenkoi, O. conferta subsp. argentea, O. alba subsp. laconica, O. biebersteinii, O. grandis, O. kachetica, O. kamularie, O. oxyodonta, O. megataphros, O. pallasii, Onobrychis spp., O. viciifolia) by the flow cytometry method and determine genetic diversity and relations within genus Onobrychis using microsatellite method. Based on the results of flow cytometric analysis carried out in the study, the mean 2C nuclear DNA contents of the accessions ranged between 2,73 pg and 1,03 pg. When chromosome number and nuclear DNA content of the accessions were correlated, it was determined that 9 accessions were diploid as 35 accessions were tetraploid (2n = 28) All the 8 SSR primers (OVK036, OVK094, OVK125, OVM033, OVK161, OVK046, OVM061, OVK174) used in the study were polymorphic. In the study, genetic diversity parameters such as the average number of alleles observed (NA = 11,625), Shannon constant (I = 0,301), Nei's unbiased genetic diversity value (uh = 0,187) were calculated and a dendrgram was constracted based on UPGMA. Based on the dendrogram, genotypes of the species included in the section Hymenobrychis generated a group together with the genotypes of the section Eubrychis which have the same ploidy level (diploid). However, polyploid genotypes tended to show generally a homogen distribution through out the dendrogram. These results may indicate that poliploid species cross with each other in nature easily and therefore, they have a complex structure.