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    Determination of morphological variation in subspecies of Isatis glauca Aucher ex Boiss. from Central Anatolia
    (2013) Görgülü, Elçin; Özbek, Özlem; Yıldırımlı, Şinasi
    Isatis glauca Aucher ex Boiss. has four subspecies: glauca, galatica Yildirimli, sivasica (Davis) Yildirimli and iconia (Boiss.) Davis, naturally growing in Turkey. In this study, 77 accessions from nine I. glauca ssp. populations were characterised in terms of variation in morphological characters, including the number of branches per plant, plant height, diameter of stem base, diameter of middle stem, diameter of apical stem, width and length of fruit, length of fruit stalk, fruit shape, fruit base shape, fruit apices shape, loculus, ondulation, apical process of fruit, fruit weight, basal length of fruit, apical length of fruit, wing width of fruit, loculus length, loculus width, length of seed, dorsal width of seed, lateral width of seed and seed weight. The number of branches had the highest value of coefficient of variation (CV), 0.21-0.86, while the fruit width had the lowest value of CV 0.08-0.20. According to Pearson's correlation and multiple regression analyses, eco-geographical factors had a substantial effect on morphological variation. A principal component analysis explained 90.61 % of morphological variation through the study of five extracted components. A dendrogram, which was constructed according to the between-group linkages method, based on squared Euclidean distances, represented a hierarchical cluster analysis of 77 accessions. The results of the principal coordinate analysis, which showed differentiation according to morphological characters between nine populations, were consistent with the dendrogram. Consequently, morphological variation of I. glauca ssp. and the significant effects of eco-geographical factors on its morphological variation were discussed. © 2013 Springer-Verlag Wien.
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    Genetic characterization of Turkish cultivated emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] landraces based on isoenzyme analysis
    (2013) Özbek, Özlem; Göçmen Taşkın, Belgin; Keskin Şan, Sibel; Eser, Vehbi; Arslan, Orhan
    Nineteen landrace populations of Turkish cultivated emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] were characterized in terms of three isoenzyme [Endopeptidase-1, Aminopeptidase-1 and Aminopeptidase-2] systems, by isoelectric focusing gel electrophoresis. For overall loci, the mean number of alleles and effective alleles were observed as 2.00 and 1.37, respectively. The mean value of gene diversity and average gene diversity, in overall loci, were detected as 0.23 and 0.07, respectively. Actual genetic differentiation and gene flow between different populations were calculated as 0.19 and 0.11, respectively. Pearson's correlation and multiple regression analyses indicated that eco-geographical variables have significant effects on isoenzyme genetic diversity. Landraces that have desirable agronomical and immunological resistance traits that makes them adaptable to climate change and different eco-geographical conditions are important genetic resources to utilise for the improvement of future crops of modern wheat varieties. There is a need to assess the genetic structure and genetic composition of important agronomical characters and to determine the magnitude of the genetic diversity currently conserved in the germplasm of landraces, both in farm fields and in ex situ collections and finally, strategies for the effective use of landraces, particularly of emmer wheat, should be planned and implemented in Turkey were discussed.
  • Küçük Resim
    Öğe
    Genetic diversity in populations of Isatis glauca Aucher ex Boiss. ssp. from Central Anatolia in Turkey, as revealed by AFLP analysis
    (2013) Özbek, Özlem; Görgülü, Elçin; Yıldırımlı, Şinasi
    Background Isatidae L. is a complex and systematically difficult genus in Brassicaceae. The genus displays great morphological polymorphism, which makes the classification of species and subspecies difficult as it is observed in Isatis glauca Aucher ex Boiss. The aim of this study is characterization of the genetic diversity in subspecies of Isatis glauca Aucher ex Boiss. distributed widely in Central Anatolia, in Turkey by using Amplified Fragment Length Polymorphism (AFLP) technique. Results Eight different EcoRI-MseI primer combinations produced 805 AFLP loci, 793 (98.5%) of which were polymorphic in 67 accessions representing nine different populations. The data obtained by AFLP was computed with using GDA (Genetic Data Analysis) and STRUCTURE (version 2.3.3) software programs for population genetics. The mean proportion of the polymorphic locus (P), the mean number of alleles (A), the number of unique alleles (U) and the mean value of gene diversity (He) were 0.59, 1.59, 20, and 0.23 respectively. The coancestry coefficient was 0.24. The optimal number of K was identified as seven. The principal component analysis (PCA) explained 85.61% of the total genetic variation. Conclusion Isatis glauca ssp. populations showed a high level of genetic diversity, and the AFLP analysis revealed that high polymorphism and differentiated subspecies could be used conveniently for population genetic studies. The principal coordinate analysis (PCoA) based on the dissimilarity matrix, the dendrogram drawn with UPGMA method and STRUCTURE cluster analysis distinguished the accessions successfully. The accessions formed distinctive population structures for populations AA, AB, E, K, and S. Populations AG1 and AG2 seemed to have similar genetic content, in addition, in both populations several hybrid individuals were observed. The accessions did not formed distinctive population structures for both populations AI and ANP. Consequently, Ankara province might be the area, where species Isatis glauca Aucher ex Boiss. originated. © 2013 Özbek et al.
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    Öğe
    Genetic variation in natural populations of Capparis from Turkey, as revealed by RAPD analysis
    (Springer-Verlag Wien, 2013) Özbek, Özlem; Kara, Aslı
    In this study, the genetic diversity of 15 Turkish natural Capparis populations was screened using the randomly amplified polymorphic DNA analysis (RAPD) technique. Ten RAPD primers produced 98 loci, 73 of which were polymorphic. The binary RAPD data were computed using the POPGENE (version 1.31), a genetic data analysis software program. According to genetic diversity analysis at locus level, the total genetic diversity (HT) and genetic diversity within population (Hs) were detected as 0.16 and 0.12, respectively. The genetic differentiation (GST) and gene flow (Nm) between populations were observed as 0.22 and 1.79, respectively. The mean number of allele per locus (na), the mean number of effective allele (nea), and the mean value of genetic diversity (He) were determined as 2, 1.20, and 0.16, respectively. According to Pearson’s correlation analysis, the mean number of allele had a strong negative correlation with wind and a strong positive correlation with rain. According to multiple regression analysis, eco-geographical factors had a significant effect on the mean number of allele, the mean number of effective allele, and the mean value of genetic diversity. The principal component analysis revealed 87.42% of total genetic variation. The principal coordinate analysis displayed the separation of population according to genetic distances based on dissimilarities matrix values on a scattered plot graph. Five different varieties, Capparis spinosa L. var. spinosa, var aegyptia and var. canescens, and Capparis ovata Desf. var. palaestina, and var. herbacea were identified in this study. Intermediate forms of plants were observed among the specimens. © Springer-Verlag Wien 2013.
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    Gliadin polymorphism in Turkish cultivated emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] landraces
    (2011) Özbek, Özlem; Göçmen Taşkın, Belgin; Keskin Şan, Sibel; Eser, Vehbi; Arslan, Orhan
    Gliadin polymorphism in 19 landrace populations of Turkish cultivated emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] was assessed using the aluminum lactic acid-polyacrylamide gel electrophoresis (A-PAGE) technique. Being a source of useful genes, landraces of wheat represent one of the most important genetic resources available to breeders for present and future genetic improvement of wheat. This is the first genetic characterization of these 19 Turkish emmer wheat landrace populations collected from their main cultivation areas. Considerably high amounts of variation were detected within and among the populations. A total of 27 alleles (na) were identified among all analyzed populations, 10 of them being unique to populations C, D, H, K, L, M, and N. The highest allele number (na = 7) was observed in populations A and L, whereas the lowest number of alleles (na = 3) was observed in populations F, G, and U. The mean number of effective alleles (nae) was 12.33, and the mean values of gene diversity, genetic differentiation, and gene flow between populations were He = 0.92, FST = 0.296, and Nm = 0.60, respectively. Certain gliadins closely linked to dough quality, such as ?-45 and ?-35, were found in 13 and 18 of the populations, respectively. According to Pearson's correlation coefficient values, gene diversity estimates had strong positive correlation (rP = 0.510; p = 0.026 at <0.05%) with latitude. The rest of the genetic data (na and nae) obtained in the present study showed no correlation with geographic (altitude, latitude, and longitude) or climatic factors (temperature and annual rainfall). Principal component analysis was performed to explain spatial genetic variation, revealing 90.044% of total genetic variation in three components. Results obtained from this study can effectively be used in developing more efficient breeding programs to improve wheat genotypes, and to direct genetic resource conservation studies. © 2011 Springer-Verlag.
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    High-molecular-weight glutenin subunit variation in Turkish emmer wheat [Triticum turgidum L. ssp. dicoccon (Schrank) Thell.] landraces
    (2012) Özbek, Özlem; Göçmen Taşkın, Belgin; Keskin Şan, Sibel; Eser, Vehbi; Arslan, Orhan
    The genetic diversity of high-molecular-weight (HMW) glutenin subunits in 18 cultivated emmer wheat landrace populations, originating from Turkey, was investigated using sodium dodecyl sulphate polyacrylamide gel electrophoresis. The mean number of alleles (n a) and effective alleles (n ea) were observed as 3.67 and 1.53, respectively. The mean values of expected heterozygosity (gene diversity) (H e) and average heterozygosity (H e,av) were calculated as 0.31 and 0.12, respectively. Actual genetic differentiation (D) and gene flow (N m) between the different populations were observed as 0.24 and 0.16, respectively. Statistical analysis of Pearson's correlation, multiple regressions and principal component analysis indicated that eco-geographical variables have a significant effect on HMW-glutenin diversity. Considering the dramatic decrease in genetic diversity of modern high-yielding cultivars, the conservation of genetic diversity in these wheat landraces, and in other old cultivars, is important for improving modern monocultures and their ability to resist biotic and abiotic conditions caused by climate changes, thus generating a wide adaption to a variety of environmental conditions. Adoptation measures for germplasm conservation of Turkish emmer wheat landraces and utilisation of their germplasm for improvement of modern wheat varieties were discussed in this study. © 2012 Springer-Verlag.
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    Polymorphism in seed endosperm proteins (gliadins and glutenins) of Turkish cultivated einkorn wheat [Triticum monococcum ssp. monococcum] landraces
    (Cereal Research Non-Profit Company, 2015) Keskin Şan, Sibel; Özbek, Özlem; Eser, Vehbi; Göçmen Taşkın, Belgin
    The objective of this study is the analysis of polymorphism in seed endosperm proteins (gliadins and glutenins) of Turkish cultivated einkorn wheat [Triticum monococcum ssp. monococcum] landraces. The genetic diversity of high-molecular-weight (HMW) glutenin subunits and the gliadin proteins in 10 landrace populations of cultivated einkorn wheat, originating from Turkey, was investigated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and ammonium lactic acid polyacrylamide gel electrophoresis (A-PAGE), respectively. For glutenins, the mean number of alleles, the mean number of effective alleles, the mean value of genetic diversity and the mean value of average genetic diversity were detected as 3.50, 2.98, 0.65 and 0.28, respectively. The genetic differentiation was 0.57, while gene flow was 0.19 between populations. For gliadins, the mean number of alleles, the mean number of effective alleles, the mean value of total genetic diversity and the genetic diversity within population were detected as 2.00, 1.21, 0.17 and 0.15, respectively. The genetic differentiation was 0.08, whereas gene flow was 6.15 between populations. STRUCTURE is a software package program for population genetic analysis, was used to infer population structures of landraces populations. The optimum value for K was obtained as 10. Considering the high number of proteins and genetic variation, and increased interest in organic products, the farming of einkorn wheat should be supported and conservation of germplasm in landraces should be maintained as important genetic resources. The landraces germplasm should be conserved for future crop improvement processes.
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    Turkish wheat landraces: Population structure and function
    (2014) Özbek, Özlem
    The cultivated tetraploid wheat (Triticum turgidum ssp. dicoccum) was derived from wild wheat in southeast Anatolia at Karacada? Mountain. There is a small core area in the region, where tetraploid wheat and many edible crop plants are cultivated. Settled human civilisation presumably started with wheat cultivation, after which traditional farmers developed landraces from germplasm collected after wheat domestication. Wheat landraces are adapted to different local environmental conditions; therefore, their gene pools display substantial genetic variation and have great potential as source of traits for good quality, resistance to adverse effects of biotic and abiotic stress factors, high yield and can be used to develop modern durum or bread wheat cultivars. Recently, however, high yielding modern wheat varieties are replacing landraces and cultivation areas and production of landraces decreased dramatically. This might lead to the loss or even extinction of landraces with invaluable germplasm. Therefore, in situ and ex situ conservation strategies should be supported to conserve the germplasm of landraces for future food security. Traditional farmers should be supported and encouraged to carry out on-farm conservation of landraces, where natural selection and continued evolution can generate new and more adapted germplasm.