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Featured researches published by Osman Tugay.


Vegetation History and Archaeobotany | 2016

Combining functional weed ecology and crop stable isotope ratios to identify cultivation intensity: a comparison of cereal production regimes in Haute Provence, France and Asturias, Spain.

Amy Bogaard; J. G. Hodgson; Erika Nitsch; Glynis Jones; Amy K. Styring; Charlotte Diffey; John Pouncett; Christoph Herbig; Michael Charles; Füsun Ertuğ; Osman Tugay; Dragana Filipović; Rebecca Fraser

Abstract This investigation combines two independent methods of identifying crop growing conditions and husbandry practices—functional weed ecology and crop stable carbon and nitrogen isotope analysis—in order to assess their potential for inferring the intensity of past cereal production systems using archaeobotanical assemblages. Present-day organic cereal farming in Haute Provence, France features crop varieties adapted to low-nutrient soils managed through crop rotation, with little to no manuring. Weed quadrat survey of 60 crop field transects in this region revealed that floristic variation primarily reflects geographical differences. Functional ecological weed data clearly distinguish the Provence fields from those surveyed in a previous study of intensively managed spelt wheat in Asturias, north-western Spain: as expected, weed ecological data reflect higher soil fertility and disturbance in Asturias. Similarly, crop stable nitrogen isotope values distinguish between intensive manuring in Asturias and long-term cultivation with minimal manuring in Haute Provence. The new model of cereal cultivation intensity based on weed ecology and crop isotope values in Haute Provence and Asturias was tested through application to two other present-day regimes, successfully identifying a high-intensity regime in the Sighisoara region, Romania, and low-intensity production in Kastamonu, Turkey. Application of this new model to Neolithic archaeobotanical assemblages in central Europe suggests that early farming tended to be intensive, and likely incorporated manuring, but also exhibited considerable variation, providing a finer grained understanding of cultivation intensity than previously available.


Molecular Phylogenetics and Evolution | 2014

Phylogeny of the Centaurea group (Centaurea, Compositae) - geography is a better predictor than morphology.

Andreas Hilpold; Roser Vilatersana; Alfonso Susanna; Andrea S. Meseguer; Igor Boršić; Theophanis Constantinidis; Rossella Speranza Filigheddu; Konstantin Romaschenko; Víctor N. Suárez-Santiago; Osman Tugay; Tuna Uysal; Bernard E. Pfeil; Núria Garcia-Jacas

The Centaurea group is part of the Circum-Mediterranean Clade (CMC) of genus Centaurea subgenus Centaurea, a mainly Mediterranean plant group with more than 200 described species. The group is traditionally split on morphological basis into three sections: Centaurea, Phalolepis and Willkommia. This division, however, is doubtful, especially in light of molecular approaches. In this study we try to resolve this phylogenetic problem and to consolidate the circumscription and delimitation of the entire group against other closely related groups. We analyzed nuclear (internal transcribed spacer of the ribosomal genes) and chloroplast (rpl32-trnL intergenic spacer) DNA regions for most of the described species of the Centaurea group using phylogenetic and network approaches, and we checked the data for recombination. Phylogeny was used to reconstruct the evolution of the lacerate-membranaceous bract appendages using parsimony. The magnitude of incomplete lineage sorting was tested estimating the effective population sizes. Molecular dating was performed using a Bayesian approach, and the ancestral area reconstruction was conducted using the Dispersal-Extinction-Cladogenesis method. Monophyly of the Centaurea group is confirmed if a few species are removed. Our results do not support the traditional sectional division. There is a high incongruence between the two markers and between genetic data and morphology. However, there is a clear relation between geography and the structure of the molecular data. Diversification in the Centaurea group mainly took place during the Pliocene and Pleistocene. The ancestral area infered for the Circum-Mediterranean Clade of Centaurea is the Eastern Mediterranean, whereas for the Centaurea group it is most likely NW-Africa. The large incongruencies, which hamper phylogenetic reconstruction, are probably the result of introgression, even though the presence of incomplete lineage sorting as an additional factor cannot be ruled out. Convergent evolution of morphological traits may have led to incongruence between morphology-based, traditional systematics and molecular results. Our results also cast major doubts about current species delimitation.


Caryologia | 2012

Karyological studies of the genus Onobrychis Mill. and the related genera Hedysarum L. and Sartoria Boiss. & Heldr. (Fabaceae, Hedysareae) from Turkey

Emine Arslan; Kuddisi Ertuğrul; Osman Tugay; Hüseyin Dural

Nine chromosome counts in several genera of the tribe Hedysareae from Turkey, six species of Onobrychis, two species of Hedysarum and one species of Sartoria, were reported and all karyotypes were prepared. Six of them are new. One of the other three reports is a confirmation of polyploidy, another report is a confirmation of chromosome count and the last report is a confirmation of both chromosome count and karyotype morphology. Except for karyotype of O. altissima, all karyotypes were presented in this study first.


Annales Botanici Fennici | 2010

Linum ertugrulii (Linaceae), a New Species from Central Anatolia, Turkey

Osman Tugay; Yavuz Bagci; Tuna Uysal

Linum ertugrulii O. Tugay, Y. Bağci & Uysal sp. nova (Linaceae) from Cihanbeyli (B4 Konya, Turkey) is described and illustrated. It is closely similar to L. flavum, L. pamphylicum and L. ciliatum, from which it differs mainly in having a stoloniferous stem, and in the leaf and floral features. Notes are presented on its habitat ecology and biogeography.


Scientific Reports | 2016

Speciation and genetic diversity in Centaurea subsect. Phalolepis in Anatolia

Jordi López-Pujol; Sara López-Vinyallonga; Alfonso Susanna; Kuddisi Ertuğrul; Tuna Uysal; Osman Tugay; Arbi Guetat; Núria Garcia-Jacas

Mountains of Anatolia are one of the main Mediterranean biodiversity hotspots and their richness in endemic species amounts for 30% of the flora. Two main factors may account for this high diversity: the complex orography and its role as refugia during past glaciations. We have investigated seven narrow endemics of Centaurea subsection Phalolepis from Anatolia by means of microsatellites and ecological niche modelling (ENM), in order to analyse genetic polymorphisms and getting insights into their speciation. Despite being narrow endemics, all the studied species show moderate to high SSR genetic diversity. Populations are genetically isolated, but exchange of genes probably occurred at glacial maxima (likely through the Anatolian mountain arches as suggested by the ENM). The lack of correlation between genetic clusters and (morpho) species is interpreted as a result of allopatric diversification on the basis of a shared gene pool. As suggested in a former study in Greece, post-glacial isolation in mountains would be the main driver of diversification in these plants; mountains of Anatolia would have acted as plant refugia, allowing the maintenance of high genetic diversity. Ancient gene flow between taxa that became sympatric during glaciations may also have contributed to the high levels of genetic diversity.


Plant Biosystems | 2017

Karyomorphology of Turkish species in Centaurea sections Centaurea and Phalolepis (Asteraceae) and implications for taxonomy

Tuna Uysal; Meryem Bozkurt; Osman Tugay; Kuddisi Ertuğrul; E. N. Şimşek Sezer; Y. B. Köse

Abstract In this paper, 31 mostly endemic and locally distributed Turkish Centaurea taxa belonging to Centaurea and Phalolepis sections were examined in terms of their karyomorphology. The basic chromosome number for all of the studied species was concurringly determined as 9(x = 9) for both sections, excluding C. hierapolitana. We also determined tetraploid and hexaploid species in spite of many species having diploid chromosome numbers. Twelve chromosome counts are reported for the first time and most of the karyotyping analyses are described for the first time via the KAMERAM program. The karyotypes had a predominance of metacentric (m) chromosomes. However, in the karyotyping of six taxa, submetacentric (sm) chromosomes were dominant. Five quantitative asymmetric indices were used to evaluate karyological features of the species. A meaningful dendrogram was carried out to assess the karyotype-symmetry conditions and describe the karyotyping relationships between different taxa.


Plant Biosystems | 2015

Centaurea sakariyaensis (Asteraceae), a new species from Turkey

Tuna Uysal; Hüseyin Dural; Osman Tugay

Abstract In this paper, a new Centaurea L. (Asteraceae) species from Turkey is described and illustrated. Centaurea sakariyaensis Uysal & Dural grows on rocky crevices in Sakarya province in north-western Anatolia. It belongs to C. sect. Centaurea L. and taxonomically its closest relative is C. wiedemanniana. Diagnostic morphological characters from a very similar taxon are provided, and a key from flora of Turkey is modified that includes related species of sect. Centaurea. The geographical distribution of the new species and species of other related taxa of the same section are mapped. The chromosome number of C. sakariyaensis, 2n = 18, counted in root tips, is also reported and illustrated.


Caryologia | 2016

Karyomorphological study of five Turkish endemic Rhaponticoides Vaill. (Asteraceae, Cardueae) species

Tuna Uysal; Ela Nur Şimşek Sezer; Meryem Bozkurt; Osman Tugay; Kuddisi Ertuğrul; Hakkı Demirelma; Hüseyin Dural

Abstract In this paper, we aimed to determine the chromosomal features of Turkish endemic Rhaponticoides species. The chromosome numbers and karyomorphology of five species were examined. The chromosomal counts confirmed the previous reports of 2n = 30 given for Rhaponticoides species growing in different countries . Although R. iconiensis had a karyotype formula of 28m + 2sm, the remaining four species all had 26m + 4sm. Rhaponticoides aytachii and R. hierroi were especially similar in asymmetry indices. Rhaponticoides iconiensis and R. phytiae had satellites in the fourth and second chromosome pairs, respectively. Having the most symmetrical chromosomes, R. amasiensis displayed an important relationship with R. iconiensis and R. phytiae in terms of total chromosome length (TCL). If we make an overall assessment in terms of chromosomal asymmetry, chromosomes indices continues in the low range for each species and this low asymmetry indeces indicate that the species have symmetric chromosomes as karyomorphology. In conclusion, this is the first report which describes the karyotypes and chromosomal asymmetry indices of Turkish endemic Rhaponticoides species.


Caryologia | 2015

Karyological studies of four endemic Centaurea L. species

Tuna Uysal; Meryem Bozkurt; Ela Nur Şimşek Sezer; Kuddisi Ertuğrul; Osman Tugay

In this paper, four endemic Centaurea species were investigated in terms of their chromosome numbers and karyomorphology. The chromosomal counts confirmed the results of previous reports, that the genus Centaurea has different basic chromosome numbers. Centaurea yaltirikii and Centaurea demirizii are diploid taxa. Centaurea yaltirikii has 2n = 18 chromosomes, and therefore has a basic chromosome number of nine, which is common in the genus Centaurea. A local endemic species, Centaurea demirizii has 2n = 16 chromosomes and a different basic chromosome number of x = 8, and this basic number is relatively rare for Centaurea. Centaurea leptophylla and Centaurea saligna are tetraploid with 2n = 36 chromosomes. We found predominance of chromosomes being metacentric and submetacentric. The results increase our karyological knowledge of these species. Moreover, this paper gives short taxonomic and morphologic notes to complement the information provided by Flora of Turkey with regards to the studied species.


Flavour and Fragrance Journal | 2003

Essential oils from flowers of Centaurea kotschyi var. kotschyi and C. kotschyi var. decumbens from Turkey

Kuddisi Ertuğrul; Hüseyin Dural; Osman Tugay; Guido Flamini; Pier Luigi Cioni; Ivano Morelli

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