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Background: Many genotoxicity tests allow us to understand the mechanism of damages on genetic material occurring in living organisms against various physical and chemical agents. One of them is the Comet test. The current study aimed to evaluate genotoxic caused by picloram and dicamba to root meristems of Allium cepa utilizing comet assay. Methods: Two different protocols were used for rooting and auxin/pesticide application. (i) A. cepa bulbs were rooted in MS medium and then treated with Murashige and Skoog (MS) medium (control) and 0.67, 1.34, 2.01, 2.68, 3.35, 4.02, and 8.04 mg/L of picloram and dicamba using aseptic tissue culture techniques. (ii) A. cepa bulbs were then rooted in bidistilled water and treated with 0 (control), 0.67, 1.34, 2.01, 2.68, 3.35, 4.02, and 8.04 mg/L of picloram and dicamba in distilled water. The A. cepa root tip cells in both treatment groups were examined using comet test to find the possible DNA damaging effects of picloram and dicamba. Results The results obtained at all the concentrations were statistically compared with their control groups. Almost at all the concentrations of Picloram and dicamba increased comet tail intensity (%) and tail moment in roots treated in MS medium. Two highest concentrations revealed toxic effect. On the other hand, DNA damaging effect of both auxins was only noted on the highest (> 4.02 mg/L) in roots treated in distilled water. Conclusions This study approve and confirm genotoxic effects of how growth regulators on plants. These findings give an evidence of DNA damage in A. cepa. Therefore, both picloram and dicamba should only be used in appropriate and recommended concentrations in agriculture to conserve ecosystem and to pose minimum threat to life.

Quality in education is one of the main concerns for governments in order to make sure the students will be able to meet the work power needs of the sector, and be able to get a job that meets their expectations in career when they graduate. In other words, it can be summarized with two words; input quality and output equality. The study aimed to investigate Turkish academics’ perceptions about the quality in higher education in Turkey. The study adopted survey method based on quantitative data. The participants comprised 53 academics from different universities in Turkey, and they were selected randomly on voluntary basis. The data were collected in distance using “The Questionnaire of Academics’ Perceptions of Quality in Higher Education” adapted from Rossner (2008) as a Google Form. The data were analyzed using descriptive statistics such as frequency and percentage. The results revealed that majority of academics in Turkey were in favor for accreditation, they were in the opinion that the curricula content should be designed in accordance with the 21st century skills and market needs, and certified programs should be offered to students in an educational environment where even academics should be observed by field experts to make sure about the quality of educational practices.

Geophytes are widely used for perfume and in the pharmaceutical industry as well as for ornamental flowers. Two million dollars is earned annually through the export of geophytes in Turkey. Because of their economic importance bulbs are frequently collected from their natural habitats. Their collection from the wild has resulted in some problems for many plant species. Iris stenophylla Hausskn & Siehe ex Baker subsp. allisonii B. Mathew is a critically endangered geophyte. In vitro production is an alternative method for the protection of this plant. In this study immature embryo and bulb scale explants were isolated and cultured on Murashige-Skoog (MS) medium supplemented with various combinations of 6-benzylaminopurin (BA) and alpha- naphthaleneacetic acid (NAA). The best result were obtained from MS medium supplemented with 1 mg/L BA and 0.25 mg/L NAA.

Habitat destruction has resulted in the extinction of many plant species from the earth, and many more face extinction. Likely, the annual endemic Mediterranean knapweed (Centaurea tchihatcheffii) growing in the Golbasi district of Ankara, Turkey is facing extinction and needs urgent conservation. Plant tissue culture, a potentially useful technique for ex situ multiplication, was used for the restoration of this ill-fated plant through seed germination, micropropagation from stem nodes, and adventitious shoot regeneration from immature zygotic embryos. The seeds were highly dormant and very difficult to germinate. No results were obtained from the micropropagation of stem nodes. However, immature zygotic embryos showed the highest adventitious shoot regeneration on Murashige and Skoog (MS) medium, containing 1 mg l(-1) kinetin and 0.25 mg l(-1) NAA. Regenerated shoots were best rooted on MS medium containing 1 mg l(-1) IBA and transferred to the greenhouse for flowering and seed set. As such, the present work is the first record of in vitro propagation of critically endangered C. tchihatcheffii, using immature zygotic embryos, and is a step forward towards conservation of this indigenous species.

Sternbergia fischeriana is an endangered geophyte and therefore in vitro micropropagation of this plant will have great importance for germplasm conservation and commercial production. Bulb scale and immature embryo explants of S. fischeriana were cultured on different nutrient media supplemented with various concentrations of plant growth regulators. Immature embryos produced higher number of bulblets than bulb scales. Large numbers of bulblets were regenerated (over 80 bulblets/explants) from immature embryos on Murashige and Skoog (MS) medium supplemented with 4 mg l−1 6-benzylaminopurine (BA) and 0.25 mg l−1α-naphthaleneacetic (NAA) or 2 mg l−12,4-dichlorophenoxyacetic acid (2,4-D) after 14 months of culture initiation. Regenerated bulblets were kept at 5 °C for 5 weeks and then transplanted to a potting mixture.

A protocol for in vitro propagation of Muscari mirum Speta, an endangered geophyte of the family Hyacinthaceae, was developed. Bulb scale, scape, leaf, and immature embryo explants were cultured on different nutrient media compositions supplemented with various concentrations of plant growth regulators (BAP, NAA, TDZ, Picloram, 2,4-D). Scape explants produced callus only. Higher numbers of bulblets were obtained from bulb scale explants than embryo explants. The highest percentage of the bulb formation (23.50 per explant) were obtained from bulb scale explants consisting of 4 scale segments cultured on Murashige and Skoog (MS) medium supplemented with 4 mg L-1 6-benzylaminopurine (BAP) and 0.25 mg L-1 alpha- naphthaleneacetic acid (NAA) after 5 months of culture initiation. Rooted bulblets which were more than 5 mm in diameter were transplanted into potting mixture of soil, vermiculite and perlite (1:1:1). The chromosome number of the root cells of in vitro induced bulblets was diploid 2n = 18.

SUMMARYIn this study, mitotic effects of gamma rays on Ekiz 1 variety belonging to Helianthus annuus L. (2n= 34) in the M0 (first irradiated seeds), M1 and M2 generations have been investigated. Seeds (M0) were irradiated with gamma rays at 10, 20, 30, 40 and 50 kR doses. Percentage of total abnormalities in the M0, M1 and M2 generations increased parallel to the increasing dose of radiation. These abnormalites have been observed as C-metaphase, chromosome stickiness, laggards and bridges with or without fragment. Mitotic index (M.I.) in the M0, M1 and M2 generations has decreased parallel to the dose increase. When the generations are compared, both the amounts of decrease in mitotic index and in the percentage of mitotic abnormalities were mostly observed in M0.

Efficient and reproducible shoot regeneration has been established from immature cotyledons and embryo axes of Hungarian vetch. Immature embryo axes showed higher regeneration capacity than immature cotyledons in most media tested. Immature cotyledons appeared to produce the highest frequency of shoot regeneration on 20 μM 6-benzylaminopurine (BA) and 2.5 μM α-naphthaleneacetic acid (NAA)-containing medium; whereas, shoot regeneration on immature embryo axes was best achieved on a medium supplemented with 5 μM each of BA and NAA. Regenerated shoots were excised and rooted in half-strength MS medium supplemented with 5 μM indole-3-butyric acid (IBA). Rooted plantlets were acclimatized to ambient conditions and later established under greenhouse conditions.

An efficient in vitro bulblet production procedure from immature zygotic embryos of endemic and endangered Muscari muscarimi Medik. was described in the current study. Zygotic embryos were first isolated from immature seeds and cultured on different nutrient media compositions supplemented with various combinations of ?-naphthalene acetic acid (NAA), picloram, dicamba, 6-benzylaminopurine (BAP), and thidiazuron (TDZ). The best bulblet regeneration (59 bulblets per explant) was achieved in Murashige and Skoog (MS) medium containing 4 mg/L BAP and 0.5 mg/L NAA after 1 year of culture initiation. Regenerated bulblets were then transferred into MS medium without plant growth regulators for rooting. Bulblets produced well-developed root systems and increased their size on this medium after 2 months. All rooted bulblets were successfully transplanted into a potting mixture and acclimatized to ambient conditions. © TÜBİTAK.

Sternbergia candida is an important endemic bulbous plant with beautiful white flowers. It grows on the rock slopes of Baba mountains under Lebanon Cedars in the Mugla province of Turkey with Mediterranean climate. The plant is vulnerable and endangered due to illegal collection for local and foreign flower industry. Fast developing tourism industry and rapid urbanization has also shown negative implications on its population. The study reports three years successful adaptation results of S. candida in the continental climate of Ankara in the Central Anatolia. Four groups of bulbs based on diameter (>2.45, 2.15-2.44, 1.85-2.14 and

Bu araşt ı rmada sar ı 85 keten Linum usitatissimum L. tohumlar ı na 10, 20, 30, 40 ve 50 kRad dozlarda gamma radyasyonu verilmi ştir. Radyasyonun M igenerasyonuna ait bitki boyu, bin tohum a ğı rl ığı , yağ oran ı , bitki ba şı na kapsül say ı s ı ve kapsül içindeki tohum say ı s ı gibi verim ögeleri üzerindeki etkisi ara şt ı rı lm ışt ı r. Genellikle düşük radyasyon dozlar ı n ı n yüksek radyasyon dozlar ı na oranla daha çok etkili oldu ğ u bulunmuştur., Gamma radiation with different doses of 10, 20, 30, 40 and 50 kRad was applied on yellow 85 flax Linum usitatissimum L. seeds in this study. The effect of radiation on yield components of M igeneration such as plant height, weight per thousand seeds, oil percentage, number of capsules per plant and number of seeds in capsule was investigated. In general, the low doses of radiation were found to be much effective with respect to high radiation doses.

Çağımızda bilim; sosyal, kültürel ve ekonomik hayatımızın önemli bir parçası olmuştur. Bu yüzden günümüzde bilimin işleyişi ve bilimin ortaya koyduğu temel fikirler hakkında yeterli bilgiye sahip ve en önemlisi, bilimin ortaya koyduğu bilgi ve tartışmalara eleştirel yaklaşabilen bireylere, yani bilimsel okur-yazar bireylere ihtiyaç duyulmaktadır. Bu bireylerin yetiştirilmesinde önemli katkıları olan öğretmenlerin sahip oldukları bilim ve bilimin doğası anlayışının öğrencilerin düşüncelerini etkileyeceği ortadadır. Bu araştırmanın amacı; 9. sınıf biyoloji dersi müfredatına entegre edilen doğrudan yansıtıcı öğretim yaklaşımına göre hazırlanan, etkinliklerle gerçekleştirilen bilimin doğası öğretiminin; öğrencilerin ve öğretmenlerin bilimin doğasına ilişkin görüşlerine olan etkisinin belirlenmesidir. Ayrıca yine bu çalışmada öğretmenlerin bilimin doğası öğretimi konusunda uzaktan eğitim yoluyla eğitim almalarının bilimin doğasına ilişkin görüşlerine ve öz-yeterliliklerine olan etkisinin belirlenmesidir. Bu amaçla araştırmada ön test-son test kontrol gruplu yarı deneysel desen kullanılmıştır. Araştırmaya 2014-2015 Öğretim yılında Konya İli Merkez Meram İlçesinde bir Anadolu lisesinde görev yapan 2 öğretmen ve 114 Anadolu Lisesi 9. sınıf öğrencisi katılmış ve tüm öğretim yılı boyunca devam etmiştir. Araştırmada veri toplama aracı olarak BDHGA- Form C (Bilimin Doğası Hakkında Görüşler Anketi), Bilimin Doğası Öz Yeterlik İnanç Ölçeği ve YYG'nin (Yarı Yapılandırılmış Görüşme) yanında Dereceli Puanlama Anahtarı, kullanılmıştır. Araştırmanın nitel verileri içerik analizi, betimsel analiz ve doküman incelemesi ile nicel verileri ise ilişkili örneklemler için t-testi ve ANOVA kullanılarak SPSS 17 paket programı ile analiz edilmiştir. Araştırmadan elde edilen hem nitel hem de nicel bulgulara göre BDÖ konusunda uzaktan eğitim yoluyla eğitim almış öğretmenin sürece dayalı hazırlanan etkinliklerle öğretim yaptığı Deney Sınıfındaki öğrencilerin bilimin doğası anlayışlarının, araştırmaya katılan diğer sınıflardaki öğrencilere göre daha fazla geliştiği görülmüştür. Ayrıca öğretmenin bilimin doğası öğretimi konusunda uzaktan eğitim almasının tek başına bir katkısı olmadığı ancak bu öğretmenin öğretim programına entegre edilen doğrudan yansıtıcı etkinlikleri kullanmasının öğrencilerin bilimin doğası anlayışlarının gelişmesine daha fazla katkı sağladığı görülmüştür. Yine bilimin doğası öğretimi konusunda uzaktan eğitim yoluyla eğitim almanın ve sürece dayalı hazırlanan etkinliklerin öğretmenlerin bilimin doğası öğretimi öz yeterlilik inançlarının gelişmesine olumlu yönde katkı sağladığı belirlenmiştir. At present, science plays an important role in our social, cultural and financial lives. So today there is a need for the people who know the process of science and have enough knowledge about the basic principles of science and above all, people who can think critically about the information and arguments that science presents. That means there is a need for the people who are scientifically literate. The perception of science and the nature of science of the teachers, who have a great impact on the education of these people, will obviously affect the ideas of the students. The purpose of this research is to identify the effect of the education of the science nature, which is integrated with 9th grade biology lesson syllabus and prepared with the explicit reflective teaching approach, on teachers' and students' ideas related to nature of the science. Meanwhile, this research is about the identification of the effects on teachers' ideas and their self sufficiency when they get distant training about teaching of the nature of the science. For that purpose, in this research, quasi experimental design with pretest and posttest control group has been used. 2 teachers and 114 students in an Anatolian High School in Meram/Konya have participated in this research in the whole 2014-2015 academic year. In this project, BDHGA Form C (a survey on the ideas about nature of the science), Self-sufficiency belief scale and YYG (semi-structured interview) and Rubic are used as data collecting tools. The qualitative data of the research has been analyzed with content analysis, descriptive analysis and document review. The quantitative data has been analyzed with the SPSS 17 software using ANOVA and T-test for related samples. According to the both quantitative and qualitative data obtained from the research, the experiment class, in which the teacher educated in distant about nature of science and has taught the topic in process based way to the students, is observed to be more developed in this topic than the other class. Also it is seen that only being educated about science nature of the teachers is not adequate. However the usage of the explicit reflective activities integrated into syllabus has contributed to the perception of the students about the nature of science topic. Moreover thanks to getting educated about the topic and the activities prepared with process based, it is indicated that teachers feel more self sufficient about the topic.