Determination of nuclear dna content and ploidy of sainfoinaccessions by flow cytometer

The objective of this study is to determine nuclear DNA content of 210 sainfoin (88 Onobrychis viciifolia, 97 Onobrychis transcaucasica and 23 Onobrychis arenaria) accessions obtained from Western Regional Plant Introduction Station, Washington, USA by flow cytometer and use the information to determine ploidy and purity of the accessions. Based on the results of the study, it is determined that the mean 2C nuclear DNA content of the O. viciifolia accessions is 2.64 pg (2.49 pg -2.78 pg), the mean 2C nuclear DNA content of the O. transcaucasica accessions is 2.65 pg (2.53 pg -2.77 pg), the mean 2C nuclear DNA content of the O. arenaria accessions is 2.63 pg (2.52 pg -2.75 pg). The mean 2C DNA contents of species were very similar. However, the mean 2C nuclear DNA content of accessions within the species were statistically different. Chromosomes of the some plants were counted by microscope in order to correlate 2C DNA contents of the accessions with their ploidy levels and it was found out that all the plants used in cytological investigations had 2n = 4x = 28 chromosomes. Therefore, it was accepted that all the accessions in the sainfoin collection screened in this study by flow cytometer had 2n = 4x = 28 chromosomes indicating they were tetraploid. Keywords: Sainfoin, Onobrychis spp., Nuclear DNA Content, Flow Cytometer, Ploidy