Determination of core DNA content and ploidynlevels of our national apple gentic sources by flow cytmetriy

Apple (Malus × domestica), the first fruit in human history, is a cross pollinated plant species. Basic chromosome number in the genus is x=17 as ploidy varies between diploid (2n=2x=34) and pentaploid (2n=5x=85). Majority of apple cultivarsare diploids while some of them are triploid. The objective of this study is to determine the nuclear DNA content and ploidy levels of the genetic materials that make up the national apple living genetic resource collection in Isparta Eğirdir Fruit Growing Research Institute by using flow cytometry for the first time. The collection consists of domestic and foreign 340 different apple varieties and genotypes,. In the study, the samples were prepared using fresh leaf tissues from healthy plants, Propidium iodide was used as a fluores cent dye. Vicia sativa (Commonvetch, cv Nilüfer) was used as an internal standard. According to there sult sobtained in the study, the 2C nuclear DNA contents of 340 apple cultivars and genotypes varied between 1,46 pg and 2,45pg. The nuclear DNA content differen cesamong apple cultivars and genotypes were statistically significant as they established clearly separated two groups such as diploids and triploids. The 2C nulear DNA content of diploids and triploids varied between 1,46 ile 1,69 pg and 2,04 ile 2,45 pg, respectively. In the end of this study, it was found out that 284 out of 340 apple cultivars and genotypes were diploid as the rest was triploid.