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Öğe On the polymorphic meadow spittebug, Philaenus spumarius (L.) (Homoptera: Cercopidae)(2000) Yurtsever, SelçukDue to its interesting biological aspects, the meadow spittlebug Philaenus spumarius has received great attention from biologists for decades. It has been one of the extensively studied species in ecology and genetics. This homopteran insect shows very high habitat diversity and therefore has a wide global distribution. Adults exhibit a heritable colour/pattern polymorphism on the dorsal surface throughout its range. A similar colour/pattern variation also occurs in certain ventral parts. Recent laboratory studies have dealt with its polyandrous aspect that is, females may mate several times with different males and the offspring of a single female may be fathered, therefore, by several males. Although the effects of multiple mating on natural populations of P. spumariusare not well known, it may have great evolutionary importance through increased genetic heterogeneity and high fitness.Öğe Somatic mutations and recombination test in Drosophila melanogaster used for investigating the genotoxicity of some food additives(2021) Çetinkaya, Aylin Yılmaz; Yurtsever, SelçukIn the present study, the effects of several food colorings, namely (Ponceau 4R (E 124), Tartrazine (E 102), and Peagreen (E 102-E 133), were investigated in vivo using the wing spot test, SMART (somatic mutation and recombinationtest), in Drosophila melanogaster. Food colorings are the food additives, which are used for improving the appearanceof food and beverages. In SMART, multiple wing hair (mwh), flare (flr3), and beaded serrate (BdS) marker genes onthe third-largest chromosome of Drosophila are used. The genotoxic effects of the food colorings on the imaginal disccells that will develop into the wing spot cells during the embryonic development of Drosophila heterozygous larvaeand the genotypic changes caused by mutation or recombination in somatic cells also play a role in the formationof mutant spots in the wings. Classes by mutant clones are as follows: small single spots containing 1-2 mwh, largesingle spots containing ?3 mwh or ?4 flr3, and twin spots containing adjacent mwh and flr3 cells (GRAF et al., 1984).Negative control medium was prepared with distilled water, while positive control medium was prepared with 1 mMEMS (ethyl methane sulfonate). According to results obtained from SMART, Ponceau 4R, Tartrazine, and Pea greendemonstrated significant results in trans-heterozygous flies (mwh/flr3) for inducing the mutant wing spots comparedto control groups at 25 mg/ml, 50 mg/ml, and 75 mg/ml exposure concentrations. On the other hand, Ponceau 4R,Tartrazine, and Pea green yielded significant results for inducing the mutant wing spots in balancer-heterozygousflies (mwh/TM3) at 25 mg/ml, 50 mg/ml, and 75 mg/ml exposure concentrations. The numbers of mutant wing spotswere increased by all three colorings depending on the concentration (X2= df=3, P<0.001). It was also determined thatthese numbers were significantly higher than the flies in the negative control medium and it suggests that these foodcolorings have genotoxic effects. However, the numbers of mutant wing spot were less than the flies in the positivecontrol medium; this finding indicates that genotoxic effects of the food colorings were not as much as the EMS.Öğe Trakya Bölgesi Istranca dağları kuş (aves) türleri(Trakya Üniversitesi, 1991) Yurtsever, Selçuk; Kurtonur, CengizÖZET Bu çalısma Istranca Dağları kuş türlerini araştırmak amacıyla yapılmıştır. Bu amaçla Vize-Saka Gölü hattı çalışma alanı olarak seçilmiş ve bu alanda Mart 1989 ve Temmuz 1990 tarihleri arasında 10 günlük aralarla toplam 79 gün gözlem yapılmıştır. Sonuç olarak 18 takım, 48 familya ve 90 cinse ait 149 kuş türü gözlenmiştir. Bunların 52 'si yerli, l'i Sonbahar göçmeni, 8» i Kış göçmeni, 7* si İlkbahar göçmeni, 2' si Yaz göçmeni, 2 'si Sonbahar- îlkbahar göçmeni, 6'sı Sonbahar-Kış göçmeni, 5* i Kış-îlkbahar göç meni, 35* i İlkbahar-Yaz göçmeni, 8' i İlkbahar-Yaz-Sonbahar göçmeni, 2' si Sonbahar-Kış-îlkbahar göçmenidir. 21 tür ise çalışma alanında arasıra gözlenmiştir. 54 türün çalışma bölgesinde kuluçkaya yattığı tespit edilmiştir.Öğe Trakya ornito - faunası üzerine Araştırmalar: I(1999) Kaya, Mustafa; Yurtsever, Selçuk; Kurtonur, CengizBu çalışmada, önemli bir kuş potansiyeline sahip olan Trakya bölgesinin çeşitli lokalitelerinde (Edirne ve çevresi, Istranca Dağlan, Iğneada ve çevresi) 1987 - 1996 yılları arasında gerçekleştirilen toplam 228 günlük kuş gözlem sonuçları değerlendirilmiştir. Bu gözlemler sonucu elde edilen bilgiler, literatür bilgileriyle karşılaştırılarak tartışılmıştır. Gözlemler sonucu, Trakya bölgesinde 50 Familyaya ait 179 kuş türü tespit edilmiş ve bu kuş türleri çeşitli bilgileri de içeren bir tablo halinde verilmiştir. Ayrıca bölgenin ornitolojik önemi üzerinde durulmuş ve bölgeyi tehdit eden sorunlar tespit edilmeye çalışılmıştır.
