Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye
Tezin Onay Tarihi: 2013
Öğrenci: ASİYE ÇİFTÇİ
Danışman: ZEKİ KAYA
Özet:The genus Populus is known as a group of forest trees for commercial exploitation. The European black poplar (Populus nigra L.), belonging to the genus Populus, is a keystone species of floodplain forests in Europe. Populus nigra has also been used as a model tree in the study of genetic resource conservation of wild relatives of cultivated plants. Turkey has over 68.000 ha poplar plantations with P. nigra and 77. 000 ha consisting of various hybrids of it. Due to overexplotation, loss of natural distribution area and introgression, P. nigra is one of the most threatened tree species in Turkey and Europe. The important and major genetic resources of European black poplar for Turkey consist of 297 clones and located in Behiçbey clone bank in Ankara with perspective of ex situ conservation programme for future plantations. To characterize genetic diversity in European black poplar populations and to provide genetic identity information for these, 297 P. nigra clones were analysed by using 12 microsatellite DNA markers. Also, 32 trees from newly discovered two natural populations were included into the analyses to compare them with the clone bank populations with respect to genetic diversity. The number of alleles ranged from 3.36 to 8.08 for 12 populations. The observed heterozygosity was found to be between 0.62 and 0.69. About 8 % of total genetic variation is between clone bank and natural populations. Great portion of total genetic variation (92%) is within the populations present in the clone bank. When all European black poplar populations (clone bank and natural populations) were evaluated with respect to genetic relatedness, clone bank and natural populations formed two separate group in the dendogram. Foreign and open pollinated populations indicated a close association to natural populations. In the current study, with the help of microsatellite DNA markers, identity problems of clones were solved. Furthermore, magnitute and pattern of genetic diversity in populations from clone bank and natural distribution areas were assessed and clonally duplicated trees were successfully determined. All populations have sufficient genetic diversity to carry out further breeding programmes for European black poplar. There have been found many vi clonally duplicated trees in the clone bank. For further breeding studies, these clones have to be replaced with new selected individuals from genetic diversity rich areas.