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Öğe The colour/pattern polymorphism of Philaenus spumarius (Hemiptera: Cercopidae) in the north-western Black Sea region of Turkey(Springer, 2010) Yurtsever, Selcuk; Akdeniz, Nilgun; Karahalil, BurcuThe heritable elytral colour/pattern polymorphism of Philaenus spumarius in north-western Black Sea region of Turkey was investigated. A total of 2,530 adult spittlebugs, 1,020 females and 1,510 males were collected and analysed in terms of the 11 most common colour forms. Nine different phenotypes, expressed by six different alleles, were determined: populi (POP), typicus (TYP), trilineatus (TRI), marginellus (MAR), flavicollis (FLA), leucocephalus (LCE), gibbus (GIB), albomaculatus (ALB), and leucophtalmus (LOP). The common phenotypes lateralis (LAT) and quadrimaculatus (QUA) of previous studies were not encountered at all. The predominant phenotype was TYP (63%) in females and males followed by POP (31%). TRI (4%) and melanics (5%) were at close proportions. However, only one site had nine phenotypes altogether. The majority of the sites had only the POP and TYP morphs. The melanic forms were found only in females.Öğe Comparison of extraction induced by emulsion breaking, ultrasonic extraction and wet digestion procedures for determination of metals in edible oil samples in Turkey using ICP-OES(Elsevier Sci Ltd, 2013) Bakircioglu, Dilek; Kurtulus, Yasemin Bakircioglu; Yurtsever, SelcukThe content of elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in edible oils (sunflower, hazelnut, canola, corn and olive oils) from Turkey was determined using inductively coupled plasma optical emission spectrometry (ICP-OES) after ultrasonic extraction, wet digestion, and extraction induced by emulsion breaking procedures (EIEB). In order to evaluate the best sample preparation procedure, EIEB procedure was compared by ultrasonic extraction and wet digestion procedures. The results in the samples (minimum-maximum in mg kg(-1)) were : 0.022-0.058, Cr 0.126-7.106, Cu 0.570-4.504, Fe 8.004-12.588, Mn 0.035-0.054, Ni 0.908-2.182, Pb 0.099-0.134 and Zn 2.206-8.982. The EIEB procedure was found to be fast, reliable, simple, and excellent in comparison with the other studied procedures. The recovery test was performed by spiking the samples with known amounts of the metals in the form of organometallic standards and applying the EIEB procedure. The recoveries were in the range of 96-109%. (C) 2012 Elsevier Ltd. All rights reserved.Öğe Differential survival and reproduction in colour forms of Philaenus spumarius give new insights to the study of its balanced polymorphism(Wiley, 2015) Silva, Sara E.; Rodrigues, Ana S. B.; Marabuto, Eduardo; Yurtsever, Selcuk; Borges, Paulo A. V.; Quartau, Jose A.; Paulo, Octavio S.1. Colour polymorphisms are common across animals and are often the result of complex selection regimes. Philaenus spumarius (Linnaeus) (Hemiptera, Aphrophoridae) shows a widely studied dorsal colour polymorphism with several described phenotypes whose variation in their occurrence and frequency, as well as their maintenance across time, have been reported. Several selective influences have been suggested to play a role, but the mechanisms underlying the maintenance of this polymorphism are still poorly understood. 2. To explore the adaptive significance of the colour polymorphism of P. spumarius, an experiment was conducted in captivity under semi-natural conditions to measure survival, reproductive success, and duration of egg maturation. 3. It was found that there was higher longevity, a higher number of oviposition events, and a higher number of eggs laid by trilineatus phenotype females than by typicus and marginellus, supporting previous reports of an increase in trilineatus frequency during the season. The duration of egg maturation did not differ among phenotypes. 4. The higher longevity and fertility of the trilineatus phenotype may compensate, for example, the higher rate of attack by parasitoids and/or higher solar radiation reflectance in this phenotype, which have already been reported in previous studies, constituting a possible mechanism for the maintenance of this polymorphism.Öğe Extraction of Cu, Fe, Mn, and Ni from Margarine Samples Using Extraction Induced by Emulsion Breaking Procedure Prior to Graphite Furnace Atomic Absorption Spectrometry and Comparison of Results to Provisional Tolerable Daily Intake Values(Oxford Univ Press Inc, 2020) Kurtulus, Yasemin Bakircioglu; Bakircioglu, Dilek; Babac, Alper Can; Yurtsever, Selcuk; Topraksever, NukteBackground: The emulsion induced by emulsion breaking (EIEB) procedure was previously reported for the extraction of copper, iron, manganese, and nickel from liquid oil samples such as vegetable oil. Objective: To optimize the EIEB procedure for determination of copper, iron, manganese, and nickel in solid oil (margarine) samples by Graphite Furnace Atomic Absorption Spectrometry (GFAAS). Methods: The extraction procedure uses a surfactant in nitric acid to form an emulsion followed by heating to break the emulsion. Optimization included variation of the test portion size, the type and concentration of the surfactant, the concentration of nitric acid in the aqueous solution, the emulsion agitation time, heating temperature, and the time required to break the emulsion. Results: Mean element concentrations of 11 margarine samples were in the following ranges: Cu 0.031-0.131 mu g/g, Fe 5.7-24.9 mu g/g, Mn 0.542-1.11 mu g/g, and Ni 0.108-0.134 mu g/g. Under the optimized extraction conditions, the detection limits (mu g/kg) were 4.8, 13, 1.5, and 23 for Cu, Fe, Mn, and Ni, respectively. The accuracy of the extraction procedure was determined by comparison to commonly used microwave digestion procedure. The EIEB results were not statistically different from the microwave digestion results when analyzed by GFAAS as determined by the statistical tests. Conclusions: The EIEB procedure was shown to be equivalent to the commonly used microwave digestion procedure for extraction of analytes from margarine samples. Highlights: The optimized EIEB extraction procedure is simple, rapid, low cost, and environmentally friendly. It has improved detection limits and allows calibration with aqueous standards.Öğe ICP-OES Determination of Some Trace Elements in Herbal Oils Using a Three-Phase Emulsion Method and Comparison with Conventional Methods(Atomic Spectroscopy Press Ltd, 2018) Bakircioglu, Dilek; Topraksever, Nukte; Yurtsever, Selcuk; Kurtulus, Yasemin BakirciogluThe concentrations of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were determined in five (Nettle, Linseed, Pumpkin seed, Sesame, and Chamomile) herbal oil samples, using inductively coupled plasma atomic emission spectrometry (ICP OES) after ultrasonic extraction (UE), wet digestion (WD), and the threephase emulsion method (TPE). The concentrations for Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were found to be 0.037-0.063, 0.014-0.085, 0.735-1.243, 2.105-19.487, 0.104-0.592, 0.105-1.582, 0.025-0.125, and 1.024-2.583 mg kg(-1), respectively. The highest concentrations in the herbal oils were Cr, Fe, Mn, and Zn, in linseed oil, Cd and Pb in sesame oil, Cu in nettle oil, and Ni in chamomile oil, respectively. The three sample preparation methods investigated were compared and it was found that the results of TPE and WD are comparable. The statistical results show that the TPE and WD methods usually give similar results.Öğe Investigation of macro, micro and toxic element concentrations of milk and fermented milks products by using an inductively coupled plasma optical emission spectrometer, to improve food safety in Turkey(Elsevier Science Bv, 2018) Bakircioglu, Dilek; Topraksever, Nukte; Yurtsever, Selcuk; Kizildere, Meltem; Kurtulus, Yasemin BakirciogluIn this study, the quantification of macro, micro and toxic elements in milk and its products was carried out using inductively coupled plasma optical emission spectrometry (ICP-OES) after using sample preparation procedures (wet digestion, dry digestion, and microwave digestion). Samples were collected from farms and markets in Edirne, Turkey. Ca, Mg, Na, K, Cu, Fe, Mn, Zn, Al, and Ba concentrations in the farm milk and its products ranged from 823 to 1499,109-476, 218-1498, 905-1694, 0.094-0.26, 2.0-3.7, 0.014-0.105,12-5.2, 0.192-0.35 and 0.075-0.191 mg kg(-1) respectively. The results in commercial milk and milk based products (minimum-maximum in mg. kg(-1)) were: Ca 791-1518, Mg 107-518, Na 221-1594, K 901-1692, Cu 0.068-0.23, Fe 2.2-4, Mn 0.019-0.087, Zn 2-5, Al 0.124-0.40 and 0.080-0.197. Macro, micro and toxic element contents of the commercial milk and its products in this study generally were higher than that of the natural samples. However, a tolerable daily diet of these elements by the Trakya region is well below the Turkish Food Codex (TFC) levels of macro, micro and toxic elements. (C) 2016 Elsevier B.V. All rights reserved.Öğe Limited polymorphism in two spittlebugs, Philaenus spumarius (Linnaeus) and P-signatus Melichar (Hemiptera: Cercopidae), in island populations from Western Turkey(Taylor & Francis Ltd, 2018) Yurtsever, SelcukTwo colour polymorphic spittlebug species, Philaenus spumarius and Philaenus signatus were recorded for the first time in Gokceada, Turkey. Three non-melanic - POP (populi), TYP (typicus), and VIT (vittata) - and three melanic MAR - (marginellus), FLA (flavicollis), and LCE (leucocephalus) - colour/pattern phenotypes of P. signatus were found. Philaenus spumarius was represented only by POP and TYP, which are expressed by a single pigmentation allele. The other six alleles were absent on this island, although they are found in most populations throughout the world. Stochastic events such as random genetic drift may be the reason for shaping the polymorphism of these two sympatric species in Gokceada. Thus, the absence of pigmentation alleles possibly indicates the founder effect.Öğe New Mitochondrial and Nuclear Evidences Support Recent Demographic Expansion and an Atypical Phylogeographic Pattern in the Spittlebug Philaenus spumarius (Hemiptera, Aphrophoridae)(Public Library Science, 2014) Rodrigues, Ana S. B.; Silva, Sara E.; Marabuto, Eduardo; Silva, Diogo N.; Wilson, Mike R.; Thompson, Vinton; Yurtsever, SelcukPhilaenus spumarius is a widespread insect species in the Holarctic region. Here, by focusing on the mtDNA gene COI but also using the COII and Cyt b genes and the nuclear gene EF-1 alpha, we tried to explain how and when its current biogeographic pattern evolved by providing time estimates of the main demographic and evolutionary events and investigating its colonization patterns in and out of Eurasia. Evidence of recent divergence and expansion events at less than 0.5 Ma ago indicate that climate fluctuations in the Mid-Late Pleistocene were important in shaping the current phylogeographic pattern of the species. Data support a first split and differentiation of P. spumarius into two main mitochondrial lineages: the western, in the Mediterranean region and the eastern, in Anatolia/Caucasus. It also supports a following differentiation of the western lineage into two sub-lineages: the western-Mediterranean, in Iberia and the eastern-Mediterranean in the Balkans. The recent pattern seems to result from postglacial range expansion from Iberia and Caucasus/Anatolia, thus not following one of the four common paradigms. Unexpected patterns of recent gene-flow events between Mediterranean peninsulas, a close relationship between Iberia and North Africa, as well as high levels of genetic diversity being maintained in northern Europe were found. The mitochondrial pattern does not exactly match to the nuclear pattern suggesting that the current biogeographic pattern of P. spumarius may be the result of both secondary admixture and incomplete lineage sorting. The hypothesis of recent colonization of North America from both western and northern Europe is corroborated by our data and probably resulted from accidental human translocations. A probable British origin for the populations of the Azores and New Zealand was revealed, however, for the Azores the distribution of populations in high altitude native forests is somewhat puzzling and may imply a natural colonization of the archipelago.Öğe Parallel colour/pattern polymorphism in three sympatric spittlebug species (Philaenus spumarius, P. signatus and Mesoptyelus impictifrons) (Hemiptera: Aphrophoridae) in Mediterranean Turkiye(Taylor & Francis Ltd, 2023) Tanyeri, Rukiye; Yurtsever, Selcuk; Tezcan, SerdarParallel colour/pattern polymorphism has been reported in the three sympatric spittlebug species Philaenus spumarius, P. signatus and Mesoptyelus impictifrons in the Mediterranean region of Turkiye. In our study, the colour phenotypes POP (populi) and TYP (typicus) are shared by all three species, whereas the phenotypes MEL (melanocephalus), PRA (praeustus) and LCE (leucocephalus) were found only in M. impictifrons. MAR (marginellus), FLA (flavicollis) and LOP (leucophthalmus) were found only in P. signatus, and TRI (trilineatus) and LAT (lateralis) were found only in P. spumarius. In combination with previous results, we show that P. spumarius and P. signatus share all eight common phenotypes except for LAT. The genetic basis of this polymorphism is well understood only for P. spumarius, yet the evolutionary strategies governing this phenomenon found in both sympatric and allopatric populations of the three species remain unknown. As the same visible elytral colour/pattern morphs occur in all three species, it will be interesting to investigate the genetic bases of these polymorphisms with further laboratory crossbreeding experiments.Öğe Some aspects of the moth (Lepidoptera, Heterocera) species diversity in Western Black Sea Region of Turkey(Univ Oradea Publ House, 2009) Okyar, Zuhal; Yurtsever, Selcuk; Aktac, Nihat; Cakan, GoekhanThe moth species were investigated in the four distinct types of habitat coniferous, beech, oak forests and shrubs including 57 different sites - of Western Black Sea Region in Turkey between the years of 2001 and 2004. A total of 207 Lepidoptera species belonging to 164 genera and 11 families was determined. Results showed that the index of diversity in the coniferous habitats (H=0.5592) was significantly higher than those of beech (H=0.3561) and oak forests (H=0.4238), but was not significantly different than those of shrubs (H=0.4921). The pooled species numbers of the coniferous habitats were the highest among the four types of habitat (P < 0.001). Moreover, the pooled number of species in the Noctuidae and Geometridae families were significantly higher (P < 0.001) than those found in the other Lepidoptera families in the study area. The pooled numbers of the species tended to decrease from June to September during the study months.Öğe What colour of flowers do Lepidoptera prefer for foraging?(Versita, 2010) Yurtsever, Selcuk; Okyar, Zuhal; Guler, NecmettinFood plant preferences of some Lepidoptera species associated with particular colour of the flowers were investigated. Based on 1,329 field observations of 43 Lepidoptera and 66 plant species, Lepidoptera showed a high tendency (G-test, G (adj) = 698.6, df = 6, P < 0.001) to use the yellow (29%) and pink (28%) coloured flowers for foraging. Compared to the other colours it was evident that plants with red flowers (2%) were not preferred. Moreover, the plants with red (H = 0.435) and yellow-white (H = 0.543) flowers were not visited by diverse Lepidoptera species. Although yellow and pink flowers were most frequently visited, the highest degrees of the Lepidoptera diversity values were associated with the plants having blue (H = 0.647) and purple (H = 0.634) flowers. Species of Nymphalidae were most numerous (14 spp.) in the study area and the members of this family were observed 430 times on 39 different plant species, but never on plants with red flowers. Pieris rapae was the most abundant species that occurred 136 times on a total of 21 different plant species of which eight had yellow flowers. But, this species has never been seen while feeding on red flowers.
