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The Cytogenetical Comparisons Of Spalax (Rodentia: Spalacidae) Populations From Middle Kızılırmak Basin, Turkey, Eşref Yüksel, Mehmet Doğan Gülkaç Jan 2001

The Cytogenetical Comparisons Of Spalax (Rodentia: Spalacidae) Populations From Middle Kızılırmak Basin, Turkey, Eşref Yüksel, Mehmet Doğan Gülkaç

Turkish Journal of Biology

Chromosomal polymorphism and speciation problem in genus Spalax has been investigated. All the specimens were identified as Spalax leucodon cilicicus Mehely, 1909. In according to karyotype analysis, two different populations were described from the field. The diploid number of Population A from south ant northwest of the field were found to be 60 and number of fundamental numbers were 80. The corresponding numbers in the Population B from northeast of the field were 54 and 74 respectively. In the result, the possibility of inversions in the Population B was discussed from evolutionary point of view and also the evolutionary background …


Effect Of Some Organophosphorus Insecticides On Soil Microorganisms, Meti̇n Diğrak, Ferdağ Kazanici Jan 2001

Effect Of Some Organophosphorus Insecticides On Soil Microorganisms, Meti̇n Diğrak, Ferdağ Kazanici

Turkish Journal of Biology

The effect of some organophosphorus insecticides [Isofenphos (=Oftanol DS 40), Phorate (=Thimet 10G and Foratox 10-G) and Fonofos] were investigated on soil microbiota (total viable bacteria, actinomycetes, anaerobic bacteria, aerobic endospores, proteolytic bacteria, cellülolytic microorganisms and yeast-mold). In the isofenphos-treated soil sample, the total viable bacteria number was found to be higher than that of the control groups during incubation. Moreover, it was observed that this treatment had no inhibitory effect on the development of the other microorganism groups. It was determined that the fonofos and phorate pesticides were had no inhibitory effect on the devel- opment of the soil …


Purification Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Meti̇n Yildirim Jan 2001

Purification Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Meti̇n Yildirim

Turkish Journal of Biology

Buchnericin LB produced by Lactobacillus buchneri LB was purified to homogeneity by a rapid and simple three-step purification procedure including freeze drying, silicic acid adsorption/desorption and cation-exchange chromatography. After the silicic acid and cation-exchange chromatography steps, the activity of buchnericin LB was recovered by 85 and 25%, and its purity increased about 111 and 2,500 fold, respectively. It was determined that the adsorption of buchnericin LB to silicic acid and cation-exchange chromatography was dependent on the pH of the suspending environment. The molecular weight of buchnericin LB was determined to be about 4.0 kDa by tricine SDS-PAGE.


Characterization Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Zeli̇ha Yildirim, Meti̇n Yildirim Jan 2001

Characterization Of Buchnericin Lb Produced By Lactobacillus Buchneri Lb, Zeli̇ha Yildirim, Meti̇n Yildirim

Turkish Journal of Biology

Lactobacillus buchneri LB isolated from a commercially fermented vegetable product produced a bacteriocin-designated buchnericin LB. It was found that buchnericin LB was heat-stable (90-121^oC for 15 min) and hydrolyzed by proteases, \alpha-chymotrypsin, trypsin, papain, proteinase K and pepsin. However, it was observed that it was resistant to catalase, peroxidase, lipase, amylases and organic solvents. Also, it was found that it retained its biological activity after exposure to pH 2.0-9.0 and after storage at -20^o and -70^oC. It was determined that buchnericin LB had a wide inhibitory spectrum, being inhibitory to the Listeria, Bacillus, Enterococcus, Micrococcus, Lactobacillus, Leuconostoc, Pediococcus, and Streptococcus …


Blood Serum Proteins Of Apodemus Flavicollis And Apodemus Hermonensis (Mammalia: Rodentia) In Turkey, Reyhan Çolak, Ercüment Çolak, Nuri̇ Yi̇ği̇t, Mustafa Sözen, Şaki̇r Özkurt Jan 2001

Blood Serum Proteins Of Apodemus Flavicollis And Apodemus Hermonensis (Mammalia: Rodentia) In Turkey, Reyhan Çolak, Ercüment Çolak, Nuri̇ Yi̇ği̇t, Mustafa Sözen, Şaki̇r Özkurt

Turkish Journal of Biology

The globulin, albumin, postalbumin, and prealbumin proteins of Apodemus flavicollis and Apodemus hermonensiswere examined by SDS-PAGE. In A. flavicollis and A. hermonensis respectively, 6-9 and 7-9 electrophoretic bands were determined in the globulin region, respectively. Both species have one band in the postalbumin zone, and two bands in the prealbumin zone. A. flavicollis differs from A. hermonensisin terms of postalbumin.


Effects Of Sewage Pollution The Structure Of The Community Of Ulva Lactuca, Enteremorpha Linza And Rocky Macrofauna In Dışliman Of Sinop, Levent Bat, Mehmet Akbulut, Murat Sezgi̇n, Mehmet Çulha Jan 2001

Effects Of Sewage Pollution The Structure Of The Community Of Ulva Lactuca, Enteremorpha Linza And Rocky Macrofauna In Dışliman Of Sinop, Levent Bat, Mehmet Akbulut, Murat Sezgi̇n, Mehmet Çulha

Turkish Journal of Biology

Untreated sewage and domestic wastes from the Sinop outfall enter the Dışliman region. The effect of this on the distribution of Ulva lactuca, Enteromorpha linza and benthic macrofauna and on enviromental parameters was determined. Increases in the growth of opportunistic green algae such as Ulva lactuca and Enteromorpha linzain response to increased nutrient supply in the Dışliman coastal ecosystems in Sinop are reported in the present study. The results of this study show that organic enrichment also increases, with Mytilus galloprovincialis (Mollusca), Erichthonius brasiliensis, Echinogammarus olivii and Amphitoes ramondi, Idotea baltica and Sphaeroma serratum(Crustacea) being the most abundant species.


Cover And Contents Jan 2001

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Identification And Evaluation Of Clinically Significant Nocardia Brasiliensis, Nocardia Farcinica And Nocardia Otitidiscaviarum Strains Using Pyrolysis Mass Spectrometry (Pyms), Kami̇l Işik, Ergi̇n Kari̇ptaş, Nevzat Şahi̇n, Alan C. Ward, Micheal Goodfellow Jan 2001

Identification And Evaluation Of Clinically Significant Nocardia Brasiliensis, Nocardia Farcinica And Nocardia Otitidiscaviarum Strains Using Pyrolysis Mass Spectrometry (Pyms), Kami̇l Işik, Ergi̇n Kari̇ptaş, Nevzat Şahi̇n, Alan C. Ward, Micheal Goodfellow

Turkish Journal of Biology

Out of a total of thirty-nine Nocardia strains, eight species of N. brasiliensis, seventeen species of N. farcinica and fourteen species of N. otitidiscaviarum were identified using Pyrolysis mass spectrometry. N428, N477 N. brasiliensis; N669, N233 N. farcinica; and N231, N232 N. otitidiscaviarum duplicated strains were clustered in their own groups. Strains belonging to Nocardia brasiliensis, Nocardia farcinica and Nocardia otitidiscaviarum formed distinct pyrogroups corresponding to clusters defined in the numerical study. It can be concluded that PyMS provides a rapid and reproducible method of evaluating the taxonomic significance of Nocadia species.


Physiological Studies On The Plant Cell Wall Degrading Enzymes Of The Rumen Bacterium Ruminococcus Flavefaciens, Emi̇n Özköse, Mehmet Sai̇t Eki̇nci̇, Numan Özcan Jan 2001

Physiological Studies On The Plant Cell Wall Degrading Enzymes Of The Rumen Bacterium Ruminococcus Flavefaciens, Emi̇n Özköse, Mehmet Sai̇t Eki̇nci̇, Numan Özcan

Turkish Journal of Biology

Two forms of Ruminococcus flavefaciens, the wild type and a trained culture of strain 17 were compared for their cellulose and xylan degradative ability when then were grown in ryegrass, cellobiose and xylan for different incubation times. No cell-associated corboxymethylcellulase (CMCase) activity was observed after 1-day incubation in cellobiose, as no supernatant activity was detected after 1 and 3 days incubation in xylan and 2 days incubation in cellobiose grown culture. Both CMCase and xylanase activities of trained culture were higher than those of wild type culture when they were grown in ryegrass. Wild type cultures, however, showed higher levels …


Application Of Green Fluorescent Protein As A Marker For Selection Of Transgenic Mouse Embryos Before Implantation, Haydar Bağiş, Levent Keski̇ntepe Jan 2001

Application Of Green Fluorescent Protein As A Marker For Selection Of Transgenic Mouse Embryos Before Implantation, Haydar Bağiş, Levent Keski̇ntepe

Turkish Journal of Biology

In this study, we evaluated the application of green fluorescent protein (GFP) from the jellyfish Aequorea victoria, for efficient selection of possible transgenic and non-mosaic mouse embryos after microinjection. We injected 353 one-cell mouse zygotes with a DNA fragment carrying Gfp gene under the control of \beta-actin gene promoter. Eighty-seven per cent (307 embryos) of the injected embryos survived after microinjection. The surviving embryos were cultured for an additional day and then analysed for detection of GFP expression using a standard fluorescein isothiocyanate (FITC) filter set attached to a microscope. In this analysis, 34 % of the two-cell stage embryos …


Availability Of Use Of Total Extracellular Proteins In Sds-Page For Typing Staphylococcus Aureus And Coagulase-Negative Staphylococci, Sefa Can Saçilik, Özlem Osmanağaoğlu, A. Hakki Sayar, Cumhur Çökmüş Jan 2001

Availability Of Use Of Total Extracellular Proteins In Sds-Page For Typing Staphylococcus Aureus And Coagulase-Negative Staphylococci, Sefa Can Saçilik, Özlem Osmanağaoğlu, A. Hakki Sayar, Cumhur Çökmüş

Turkish Journal of Biology

A total of nineteen Staphylococcus references, nine of which are Staphylococcus aureus and ten coagulase-negative Staphylococci (CNS), were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Whole-cell protein (WCP) profiles obtained by SDS-PAGE were compared with banding patterns produced by SDS-PAGE of total extracellular proteins (TEP). No report has yet been issued which explains Staphylococcus typing by SDS-PAGE of extracellular proteins. SDS-PAGE of whole-cell extracts did not usefully distinguish different isolates of Staphylococci. Our preliminary results suggest that SDS-PAGE of total extracellular proteins provides additional criteria and characteristic banding patterns for the study of the epidemiology and characterization of Staphylococci. …


Nitric Oxide Synthase In The Skeletal Muscle And Arterioles Of Rats With Streptozotosin-Induced Diabetes Mellitus, Ci̇han Demi̇rci̇, Kadri̇ye Akgün Dar, İlhan Uyaner Jan 2001

Nitric Oxide Synthase In The Skeletal Muscle And Arterioles Of Rats With Streptozotosin-Induced Diabetes Mellitus, Ci̇han Demi̇rci̇, Kadri̇ye Akgün Dar, İlhan Uyaner

Turkish Journal of Biology

Nitric oxide synthase (NOS) that uses NADPH as a cofactor is an enzyme which produces nitric oxide (NO) from L-arginine. Endothelial-derived (eNOS), inducible (iNOS) and neuronal (nNOS) nitric oxide synthase are 3 known isoforms. Endothelial NO regulates the vascular tonus and causes the dilatation of vessels, while NOS localized in the sarcolemma of striated muscle plays a role in the regulation of muscle hemodynamics. Many authors have found differences in NO production in some pathological conditions such as diabetes mellitus (DM), hypertension and atherosclerosis. In this study, NADPH-diaphorase (NADPH-d) was histochemically employed to explore any changes in NO production associated …


Transient Eexpression Of B-Glucuronidase Reporter Gene In Sainfoin (Onobrychis Viciifolia Scop.) Cotyledons Via Microprojectile Bombardmen, Sertaç Önde, Cengi̇z Sancak, Suzan Altinok, Melahat Bi̇rsi̇n, Murat Özgen Jan 2001

Transient Eexpression Of B-Glucuronidase Reporter Gene In Sainfoin (Onobrychis Viciifolia Scop.) Cotyledons Via Microprojectile Bombardmen, Sertaç Önde, Cengi̇z Sancak, Suzan Altinok, Melahat Bi̇rsi̇n, Murat Özgen

Turkish Journal of Biology

Transient \beta-glucuronidase reporter gene (GUS) expression was visualised in whole cotyledons of sainfoin (Onobrychis viciifolia Scop.) after microprojectile bombardment with pBI221.23 DNA. Optimum rupture disk pressure and sample plate distance were determined to be 1350 psi and 6 cm, respectively. Mean gold particle diameter of 1.0 µm and 48 h post-bombardment histochemical GUS assay was found to be superior to 1.6 µm gold particles and 120 h post-bombardment GUS assay. Microscopic analysis revealed the localisation of the gold particles predominantly in the epidermal cell layer, whereas less than 1% of the particles were localised in sub-epidermal cells, as deep as …


Determination Of Some Fungal Metabolite As Influenced By Temperature, Time, Ph And Sugars By Bioassay Method, Meti̇n Diğrak, Sami̇ Özçeli̇k Jan 2001

Determination Of Some Fungal Metabolite As Influenced By Temperature, Time, Ph And Sugars By Bioassay Method, Meti̇n Diğrak, Sami̇ Özçeli̇k

Turkish Journal of Biology

This study investigated the fungal biomass and inhibition of Bacillus megaterium DSM 32 with extracts of Fusarium equiseti, Penicillium italicum, Penicillium digitatum, Aspergillus candidus and Aspergillus parasiticus in modified Czapek Dox Broth (mCDB) as affected by temperature (6, 15, 25 °C), incubation time (up to 4 wk), pH (3.0, 5.0 and 8.0) and glucose the and fructose (4.0, 6.0 and 9.0%). The biomass production was greatest at 25 °C. In general, biomass production was greatest in media containing an addition of 4.0% glucose or 6.0% fructose; however, bacterial inhibition production was reduced by elevated sugars in mCDB over a 4-wk …


Nucleotypic Effects In Different Genotypes Of Vicia Sativa L., Serap Çeli̇kler, Rahmi̇ Bi̇laloğlu Jan 2001

Nucleotypic Effects In Different Genotypes Of Vicia Sativa L., Serap Çeli̇kler, Rahmi̇ Bi̇laloğlu

Turkish Journal of Biology

Seven cultivar varieties of Vicia sativa L. were used. Nucleotypic effects of telophase (2C) nuclear DNA amounts on seed weight, percent mitotic index, stomatal frequency/mm^2, chlorophyll a and b content, root growth and shoot growth were determined. No correlation was observed between the DNA contents and the percent mitotic index, chlorophyll a and b content, or root growth of the cultivar varieties. However a significant correlation was observed between DNA content and the seed weight, stomatal frequency and shoot growth of the cultivar varieties.


Comparison Of 22 Taurus Cedar (Cedrus Libani A. Rich.) Origins By Seedling Morphological Distance, Zeki̇ Yahyaoğlu, Ali̇ Demi̇rci̇, Nebi̇ Bi̇li̇r, Musa Genç Jan 2001

Comparison Of 22 Taurus Cedar (Cedrus Libani A. Rich.) Origins By Seedling Morphological Distance, Zeki̇ Yahyaoğlu, Ali̇ Demi̇rci̇, Nebi̇ Bi̇li̇r, Musa Genç

Turkish Journal of Biology

In this study, seeds were collected from 22 seed stands of Taurus cedar (Cedrus libani A. Rich.), and these seeds were sown at the Black Sea Technical University Nursery in 1995. The main morphological characteristics of 2+0 year old seedlings were measured in 1997. Values of seedling morphological distance were calculated using the Penrose formula to compare the origins in terms of morphological characteristics. According to the Penrose formula, when the values of morphological distance (P_{ij}) approach zero, the similarity between origins increases. Consequently, the most similar origins were Mugla-Arpacik and Isparta-Belcegiz2 (P_{18,22}=0.040), while the most different origins were Mersin-Aslankoy …


Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner Jan 2001

Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner

Turkish Journal of Biology

Rainbow trout (Oncorhynchus mykiss) were fed diets containing three different concentrations of crude protein (56.3%, 51.7% and 45.8%) and digestible energy (21.3, 20.3 and 18.8 MJ/kg), and the effects of dietary protein and energy level on gastric evacuation and return of appetite times were investigated. Gastric evacuation determinations were achieved by slaughtering 8 fish every 6 hours until no residue was found in the cardiac stomach of fish. Return of appetite experiments were conducted by re-feeding groups of trout every 4 or 6 hours following the first feeding. The data obtained from each process was modelled by regression analysis and …


Cover And Contents Jan 2001

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2001

Cover And Contents

Turkish Journal of Biology

No abstract provided.


The Role Of P13-Kinase On Melanoma Cell Adhesion And Migration, Zerri̇n Seller, Ian R. Hart Jan 2001

The Role Of P13-Kinase On Melanoma Cell Adhesion And Migration, Zerri̇n Seller, Ian R. Hart

Turkish Journal of Biology

Integrins are responsible for anchoring cells to the extracellular matrix and also can initiate intracellular signal pathways. The interaction between integrins and the extracellular matrix results in activation of PKC, PTKs, p21Ras, MAPK and PI3-kinase. The \alpha4\beta1 integrins are expressed mainly on haematopoietic cells and also appear on several tumour types. The adhesion of \alpha4\beta1 to VCAM-1 is an essential step for lymphocyte extravasation during the inflammatory response. Furthermore, the interaction of \alpha4\beta1, expressed on tumour cells, with VCAM-1, might have a role in tumour cell extravasation. We examined the role of PI3-kinase activation in \alpha4\beta1-mediated melanoma cell adhesion and …


Production Of Ethanol From Beet Molasses By Ca-Alginate Immobilized Yeast Cells In A Packed-Bed Bioreactor, Yekta Göksungur, Neşe Zorlu Jan 2001

Production Of Ethanol From Beet Molasses By Ca-Alginate Immobilized Yeast Cells In A Packed-Bed Bioreactor, Yekta Göksungur, Neşe Zorlu

Turkish Journal of Biology

The continuous production of ethanol from beet molasses by Ca-alginate immobilized Saccharomyces cerevisiae in a packed-bed bioreactor was investigated. The temperature was maintained at 30°C and the dilution rate was 0.22 h^{-1}. Maximum ethanol (4.62%), theoretical yield (82.9%) and volumetric productivity (10.16 gl^{-1}h^{-1}) were obtained from the beet molasses medium containing 10.90% total sugar with 2.0-2.4 mm diameter beads prepared from 2% (w/v) sodium alginate solution. At higher substrate concentrations, substrate was recirculated through the packed-bed bioreactor to increase yields and to decrease residual sugar content. The bioreactor system was operated at a constant dilution rate of 0.22 h^{-1} for …


Effects Of Cd^{2+}, Zn^{2+}, Li^+ And Al^{3+} On The Fertilization-Induced Membrane Potential Changes In The Egg Of The Frog Rana Cameranoi, Şeref Erdoğan, Gülay Loğoğlu, Kerem Tuncay Özgünen, Tuncay Özgünen Jan 2001

Effects Of Cd^{2+}, Zn^{2+}, Li^+ And Al^{3+} On The Fertilization-Induced Membrane Potential Changes In The Egg Of The Frog Rana Cameranoi, Şeref Erdoğan, Gülay Loğoğlu, Kerem Tuncay Özgünen, Tuncay Özgünen

Turkish Journal of Biology

The apparent change in the egg membrane potential at fertilization gives rise to fertilization potential (FP). FP is the initial, transient electrical block to polyspermy as shown in most species especially those exhibiting external fertilization, and it protects the egg from a second sperm entry until the permanent, mechanical block is set up. Polyspermy risk is increased when this effective electrical block cannot reach a certain peak value or when it is of short duration. On the other hand, metal accumulation in the external environment is potentially toxic to living beings, and we aimed in the present study to evaluate …


Assessment Of Polymorphic Aflp Markers In Triticum Durum And Aegilops Sp., Aytül İnci̇rli̇, Hati̇ce Bi̇lgi̇ç, Mahi̇nur S. Akkaya Jan 2001

Assessment Of Polymorphic Aflp Markers In Triticum Durum And Aegilops Sp., Aytül İnci̇rli̇, Hati̇ce Bi̇lgi̇ç, Mahi̇nur S. Akkaya

Turkish Journal of Biology

Compared to other Polymerase Chain Reaction (PCR) based molecular markers, the Amplified Fragment Length Polymorphism (AFLP) marker system probably requires more technical expertise for the sequential enzymatic reaction steps. In addition, the reproducibility of the AFLP marker patterns is much more dependent on the quality and the purity of the DNA samples to be processed. The present study describes the optimization of reaction conditions and determination of the most polymorphic selective amplification primer sets in a comparison of winter and spring type Turkish durum wheat varieties. AFLP products resulted in about 100 bands, and the number of polymorphic AFLP loci …


Effects Of Photoperiod And Melatonin Infusions On Body Weight In Pinealectomized Juvenile Siberian Hamsters (Phodopus Sungorus), Bülent Gündüz, Alper Karakaş Jan 2001

Effects Of Photoperiod And Melatonin Infusions On Body Weight In Pinealectomized Juvenile Siberian Hamsters (Phodopus Sungorus), Bülent Gündüz, Alper Karakaş

Turkish Journal of Biology

We examined the effects of daily melatonin (Mel) infusions in pinealectomized prepubertal male Siberian hamsters in three different conditions. In one study we investigated the body weight maturation response to one hour daily infusions of 10 ng, 25 ng, or 50 ng of Mel in pinealectomized hamsters. Animals received, at day 15 of life, programmed subcutaneous infusions of Mel or vehicle at one of five time points (1900-2000, 2000-2100, 2100-2200, 2400-0100, and 0300-0400 hours) for 30 days. In long-day-born (16L) animals, Mel infusion right after lights off (2000-2100 hours) significantly inhibited body growth; this dose was ineffective at other times. …


Antiviral And Cytotoxic Activities Of Extracts From The Cell Cultures And Respective Parts Of Some Turkish Medicinal Plants, Atalay Sökmen Jan 2001

Antiviral And Cytotoxic Activities Of Extracts From The Cell Cultures And Respective Parts Of Some Turkish Medicinal Plants, Atalay Sökmen

Turkish Journal of Biology

Extracts from respective parts and cell cultures of some Turkish medicinal plants have been assessed for their antiviral and cytotoxic properties. None of the extracts tested showed notable activity against herpes simplex viruses (HSV-I and II), but a slight antiretroviral activity against HIV-I was determined in an extract from Hypericum capitatum cell cultures. On the other hand, according to cytotoxic activity test results against brine shrimp (Artemia salina), an activity level of LD_{50} at 34.9 µg/ml was found on the extracts of Ecbalium elaterium cell cultures.


Cover And Contents Jan 2001

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Molecular Characterization Of The Gene Encoding For The Salivaricin B Activity And Its Flanking Sequences, Osman Çataloluk Jan 2001

Molecular Characterization Of The Gene Encoding For The Salivaricin B Activity And Its Flanking Sequences, Osman Çataloluk

Turkish Journal of Biology

Lactic acid bacteria (LAB) produce many different antimicrobial proteins, some of which have potential in food preservation. The molecular analysis of bacteriocins has gained much attention and has advanced rapidly in recent years, and it became routine to analyze the way in which bacteriocins are expressed and translocated. Since they are associated with foods of plant and animal origins, the shared interest is that they can be utilized as a vector to deliver the active constituents at the target in the gastrointestinal tract after digestion and be used in therapy. In this respect, the molecular pattern of the expression and …


Pulsed-Field Gel Electrophoresis (Pfge) Technique And Its Use In Molecular Biology, Esi̇n Basim, Hüseyi̇n Basim Jan 2001

Pulsed-Field Gel Electrophoresis (Pfge) Technique And Its Use In Molecular Biology, Esi̇n Basim, Hüseyi̇n Basim

Turkish Journal of Biology

In recent years, the use of pulsed-field gel electrophoresis (PFGE) in the molecular biology area has been subject to much research. PFGE is a powerful tool for characterizing various strains at the DNA level, obtaining relevant information on genome size and constructing the physical and genetic map of the chromosome of bacteria that are poorly understood at the genetic level as well as in separating chromosomes in microorganisms, and in the long-range mapping of mammalian genes. PFGE also has advantage of examining the elongated and oriented configuration of large DNA molecules in agarose gels at finite field strengths. In this …


Callus Induction And Plant Regeneration From Mature Embryos Of Oat (Avena Sativa L.), Melahat A.Bi̇rsi̇n, Sertaç Önde, Murat Özgen Jan 2001

Callus Induction And Plant Regeneration From Mature Embryos Of Oat (Avena Sativa L.), Melahat A.Bi̇rsi̇n, Sertaç Önde, Murat Özgen

Turkish Journal of Biology

The aim of this study, which was conducted in Ankara University, Faculty of Agriculture, Department of Field Crops, biotechnology laboratory in 1998-1999, was to determine the callus induction and plant regeneration capacity of oat (Avena sativa L.). The mature embryos of 10 oat genotypes were utilised for callus induction. The statistical analysis of the results revealed that callus induction and plant regeneration capacity were dependent on the oat genotype. However, a significant relationship was not established between callus induction and regeneration capacity and, furthermore, the number of regenerated plants was determined to be directly related to the callus production capacity.


In Vitro Inhibition Of The Mycelial Growth Of Some Root Rot Fungi By Rhizobium Leguminosarum Biovar Phaseoli Isolates, İbrahi̇m Özkoç, Muhammet Hani̇fi̇ Deli̇veli̇ Jan 2001

In Vitro Inhibition Of The Mycelial Growth Of Some Root Rot Fungi By Rhizobium Leguminosarum Biovar Phaseoli Isolates, İbrahi̇m Özkoç, Muhammet Hani̇fi̇ Deli̇veli̇

Turkish Journal of Biology

In solid medium, the effects of twenty-three Rhizobium leguminosarum biovar phaseoli isolates on the mycelium development of the phytopathogenic fungi of three different genera (Fusarium oxysporum, Pythium ultimum and Rhizoctonia solani) were tested in vitro. The experiments were achieved by applying the superimpose dual culture technique. Most of the rhizobia tested inhibited the fungal development. The inhibition rates displayed differences in accordance with the bacteria and fungi isolates utilized. However, the inhibitory effect of the rhizobia occurred most on the isolates of Fusarium and Pythium species (up to 30.35% and 29.75% respectively) and least on those of Rhizoctonia species (16.03%). …