Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye
Tezin Onay Tarihi: 2018
Öğrenci: ÇİĞDEM KANSU
Danışman: ZEKİ KAYA
Özet:Poplar is one of the economically most important plants growing in Anatolia. Developing and growing world population and ascending demand for energy sources increased the genetic studies on poplars. There are four poplar species that have economical value and distributed naturally in Turkey; Populus nigra, Populus tremula, Populus alba and Populus euphratica. Populus euphratica, which can survive in salty and calciferous soils and known as Euphrates poplar, is resistant for low moisture and long summer drought. Having economical value for these respects, this species is distributed in East Mediterranean and Southeastern Anatolia. The species possesses great importance for both renewable energy resources and persistence of a healthy river ecosystem. Due to decreasing water resources with increased population and habitat destructions by human activities, the distribution area of this species become narrower gradually as well as loss of gene sources. Hence, searching for potential genetic diversity present in species’ genetic resources is of great importance in terms of conservation (in situ and ex situ), breeding and use. In this PhD Thesis, genetic structure and diversity of Populus euphratica populations in the Göksu river ecosystem were studied with 21 microsatellite DNA (SSR: single sequence repeats) markers. Results demonstrated reduced level of genetic diversity with low heterozygosity values (Ho:0.50±0.07, uHe:0.49±0.06). Severe past reductions in population sizes have resulted in loss of genetic variation for the species. Native populations of this species in the Göksu river are experiencing gene pool shrinkage and are in great danger of collapsing, mainly because of anthropogenic pressures. With great number of private alleles and slightly higher heterozygosity values The Euphrates river population is shown to be an effective candidate of genetic resource for future conservation studies. Effective breeding and conservation programs including in situ conservation of Euphrates poplar stands in the Göksu river and ex situ conservation by establishing gene banks and clone banks in order to preserve germplasm resources should be initiated immediately. The conservation of these genetic resources is of great importance and priority should be given for fast and reproducible actions.