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Specific mechanisms contributing to the antifungal activity of α-thujone, one of the main compounds of essential oils in herbs, against Fusarium graminearum, which causes various diseases of cereals, were studied for the first time. Minimum inhibitory concentration (MIC) value of α-thujone was 3.2 μg μL−1 for F. graminearum. Its toxigenic effect was confirmed by WST-1-based cytotoxicity assay. Due to α-thujone treatment, changes in genomic template stability (GTS), type II and III methylation profiles were detected. GTS rates were calculated as 89.33 and 94% according to random amplified polymorphic DNA (RAPD) and inter-retrotransposon amplified polymorphism (IRAP) assays, respectively. Mean values of polymorphisms were 28.92 and 36.42% by evaluating digestion profiles. Gene expression analysis showed α-thujone caused upregulation of mgv1, mst20 and cat genes but downregulation of tri5. Fold change values were 1.86 ± 0.14, 3.10 ± 0.03, 2.56 ± 0.078 and 0.43 ± 0.15 respectively. The acridine orange-ethidium bromide (Ao/Eb) and 2′,7′-dichlorodihydrofluorescein diacetate (DCF-DA) staining assays revealed that α-thujone treatment triggers apoptosis and oxidative stress in F. graminearum at cellular level. Additionally, 6.51-fold increase in catalase activity in comparison with the control was detected. There were no statistically significant changes in water loss rates (WLRs) when Hordeum vulgare L. cv. Akhisar seedlings were treated with α-thujone. According to the water loss rate values, α-thujone is not a potential abiotic stress factor that negatively affects the physiological development of barley plantlets. Outcomes showed that α-thujone leads to serious morphological, genetic, epigenetic, cellular alterations on F. graminearum, so could be a candidate as an alternative herbal antifungal compound.

In this study, the phylogenetic relationship among Fusarium graminearum Schwabe isolates was established for the first time based on mitochondrial cox3 and rnl gene variations. The genes were amplified from 45 isolates purified from Türkiye and Iran together with 2 Korean strains by polymerase chain reaction. The amplicons were sequenced and nucleotide polymorphisms were detected by alignment. The phylogenetic relationship was constructed by using PAUP 4.0a with the maximum parsimony method. Fragments with 477 bp length, belonging to cox3, were obtained from 46 samples; 1547 bp-amplicons of rnl were produced from 45 samples. Sequence similarities were calculated as 30-100 % and 17-94 % for cox3 and rnl, respectively. Nucleotide variations within the rnl was found higher than within cox3. It was shown that SNPs and in-dels, found in coding regions, cause a codon change and may alter more than one codon by causing frame shift without affect gene functions. Bootstrap values belonging to cox3 and rnl dataset was found ranging from 57 to 84 %, and 54 to 100 %, respectively. Parsimony analysis revealed that Korean isolates were in monophyletic relationship with Turkish and Iranian isolates. It is proposed that the methodology can be applied to other fungal species because the phylogenetic relationships at the intraspecific level are able to establish among Fusarium species based on mitochondrial gene variation., Bu çalışmada, mitokondriyal cox3 ve rnl genlerinin varyasyonlarına dayalı olarak Fusarium graminearum izolatları arasındaki filogenetik ilişki ilk kez ortaya kondu. cox3 ve rnl genleri polimeraz zincir reaksiyonu ile 2 Kore suşu ile Türkiye ve İran'dan saflaştırılan 45 izolattan çoğaltıldı. Amplikonlar dizilendi ve hizalama analizleri ile nükleotid polimorfizmleri tespit edildi. Filogenetik ilişki, maksimum tutumluluk yöntemiyle PAUP 4.0a programı kullanılarak oluşturuldu. 46 örnekten cox3'e ait 477 bp uzunluğunda fragmentler çoğaltılırken; rnl genine ait 1547 bp-amplikon 45 örnekten çoğaltıldı. cox3 ve rnl için dizi benzerlikleri sırasıyla %30-100 ve %17-94 aralığında hesaplandı. rnl gen bölgesinde, cox3’e kıyasla nukleotid varyasyonlarının daha yüksek oranda taşındığı belirlendi. Kodlama bölgelerinde bulunan SNP'lerin ve in-del'lerin gen fonksiyonlarını etkilemeden çerçeve kaymasına neden olduğu ve bu varyasyonların birden fazla kodonu değiştirebildiği belirlendi. Filogenetik analizlerle hesaplanan cox3 ve rnl veri setine ait bootstrap değerleri sırasıyla %57 ile %84 ve %54 ile %100 arasında hesaplandı. Parsimoni analizi, Kore izolatlarının Türk ve İran izolatları ile monofiletik ilişki içinde olduğunu ortaya koydu. Fusarium’da tür içi filogenetik ilişkilerin mitokondriyal gen varyasyonuna dayalı olarak belirlenebilmesi nedeniyle yöntemin diğer mantar türlerine de uygulanabileceği önerilmektedir.

Nine lactococcal adhesin and two pneumococcal virulence genes were characterized in twenty Lactococcus garvieae strains obtained from rainbow trout, and also one human isolate by PCR. Findings showed that all strains carried adhPsaA (522 bp), LPxTG-1 (947 bp), adhCI (490 bp), and purB (864 bp) while some of the strains had adhPav (1048 bp), LPxTG-2 (767 bp), LPxTG-3 (231 bp), adhCII (732 bp), adh (398 bp) and SP_0121 (966 bp). High nucleotide homologies (85-99%) of adhCI, adhCII, adh, adhPav, adhPsaA, LPxTG-1, LPxTG-3 involved in bacterial adhesion were determined between L. garvieae strains and reference Lg2. Genes containing polymorphisms among strains were not considered to be directly involved in bacterial pathogenesis. The amplification of LPxTG-3 only in fish isolates showed that it might be responsible for coding the host-specific virulence factor. However, undetermined amplicons demonstrated that LPxTG-4 could not be used as a host-specific gene marker. Pneumococcal purB and SP_0121 have been experimentally detected in L. garvieae genome for the first time. Consequently, both purB and SP_0121 can be used as a virulence marker for L. garvieae. Findings provided valuable knowledge about L. garvieae pathogenesis and, will contribute to identify the appropriate genomic targets to develop new therapeutics against the lactococcosis.

Objective: Fusarium spp. cause Fusarium head blight (FHB) and crown rot (CR) diseases. They also have harmful effects on animal and human health through their mycotoxins. Within the scope of this study, F. graminearum and F. culmorum isolates were purified from wheat ears and stalks contaminated with phytopathogens, which had been collected from various regions of Turkey, were identified and characterized by conventional and molecular methods. Materials and Methods: Sixty-eight Fusarium samples were isolated by single spore analysis and classified according to their macroconidia shape and size. Morphologically characterized samples were verified by amplification of SCAR markers. Their mating types (MAT) and chemotypes were also determined through polymerase chain reaction (PCR). Results: Thirty-eight F. graminearum and 30 F. culmorum isolates were identified via amplification of UBC85 and OPT18 SCAR markers, respectively. All isolates were determined as trichothecene producers by amplification of the tri5 gene. All F. graminarum isolates carry both MAT-1 and MAT-2 loci, whereas 7 of F. culmorum isolates were also determined as MAT-1 and 23 of them as MAT-2 mating types. Deoxynivalenol production capacity of all isolates was identified by tri13 amplification for chemotype determination. Conclusion: Routine monitoring of phytopathogens and their mycotoxin levels is a requirement since their annual levels may vary depending on environmental factors. This work provides knowledge about the distribution of Fusarium spp. leading to FHB and CR in different regions of Turkey between 2010 and 2020. Also, their chemotypes were demonstrated. Our studies will contribute to disease profiling and it is the first step in disease management.

Intraspecific and interspecific diversity between Phoenix theophrasti individuals (92 from Turkey and 70 from Crete, Greece) and P. dactylifera specimens (28 from Turkey) were investigated by inter-simple sequence repeat (ISSR) analysis. A total of 45 polymorphic fragments, 360–3454 bps long, were produced. Intraspecific diversity for P. dactylifera was 26.63% and similarities ranged between 0.5 and 1. In the constructed dendrogram, P. dactylifera specimens clustered together in the first main group, outside branches consisting of P. theophrasti samples that generated the second main group. The intraspecific diversity for Turkish P. theophrasti populations was found to be 18.60% and for Cretan populations 13.45%. Antalya–Kumluca–Karaöz samples were grouped outside the branches of the remaining P. theophrasti samples. All three Cretan populations formed their own, separate branch. Datça–Eksera Stream samples together with two Datça–Hurmalıbük specimens constituted a group excluding Datça–Hurmalıbük and Bodrum–Gölköy specimens. Five Bodrum–Gölköy genotypes were clustered separately. Gene flow (Nm) values among populations were estimated from 0.157 to 59.615. AMOVA analysis revealed the percentages of variance among and within Phoenix populations: 73% and 27%, respectively. The first three principal coordinate components accounted for 37.60, 29.32 and 20.04%, respectively, thus the total variance obtained from the first three principal coordinate components was 86.96%. A positive correlation between geographic and genetic distances of populations was detected by Mantel tests (Rx,y = 0.44, p = 0.04). The populations were classified into four clusters by STRUCTURE analysis, supported the PCoA data. To conclude, ISSR results support that P. dactylifera and P. theophrasti are different species. Moreover, the findings not only revealed relationships between natural Phoenix theophrasti populations but also supported the identification of the P. theophrasti individuals that are phenotypically differentiated in the divided Bodrum–Gölköy population (P. theophrasti subsp. golkoyana). This work was supported by the Scientific Research Projects Coordination Unit of Isik University, Project No. 16A401. Publisher's Version

Since ancient times the importance of food in human health has been known and their relationship was highlighted by Hippocrates in the 5th Century BC...

To characterize the isolates of F. graminearum and F. culmorum fungi from Turkey and Iran, we performed ISSR analysis with 18 non-anchored and 23 anchored (including ten novel) primers. Amplification product sizes were 0.2-3.5 kb. In total, 405 bands were scored, 24 of which (5.92%) were polymorphic. The similarities among F. graminearum isolates were calculated as 62.3-99%, and among F. culmorum as 65.7-94.3%. Moderate genetic variation at intra- and inter-specific levels was determined, and the average intraspecific genetic diversity values were 80.65% for F. graminearum, and 80% for F. culmorum. Cluster analysis separated the isolates into two main clades. Group I consisted of F. culmorum isolates from Turkey that produced DON mycotoxin. Group II contained all F. graminearum isolates that were deoxynivalenol (DON) and nivalenol (NIV) chemotypes from Turkey and Iran. Both groups I and II were divided into two subgroups including their divisions. Phenons in group II included isolates distributed in the same geographic region. ISSR markers clustered isolates within a definite order according to their species. Isolates from the same agro-ecological locations were also kept together in subdivisions. The novel ISSR markers developed for the first time in this study contribute to differentiating between Fusarium isolates according to their species and geographic regions.

Background Identification and quantification of mycotoxins produced by Fusarium species are important in controlling fungal diseases. Objectives Potential of zearalenone, butenolide and fusarin C production was investigated in five Fusarium graminearum and five F. culmorum isolates at molecular level. Materials and methods Presence of PKS13, FG08079.1 and PKS10 genes, associated with production of zearalenone, butenolide and fusarin C, respectively, were confirmed by PCR. In addition, expression levels of them together with housekeeping gene (β-tubulin) were detected by real time PCR. Results PKS13 and FG08079.1 transcripts were determined in all isolates, while PKS10 specific primers failed to amplify any product, indicative of no expression. ΔΔCTCT of PKS13 was ranged between 1.79E-03-3.97E-03 and for FG08079.1 was between 0.25E-03 and 6.02E-03. The highest PKS13 expressions were 3.86E-03 in F. graminearum F9 and 3.97E-03 in F. culmorum F16. Maximum FG08079.1 expressions were calculated as 6.02E-03 and 3.81E-03 in F. graminearum 2F and F. culmorum F2, respectively. Conclusions We revealed that ten Fusarium isolates produced zearalenone and butenolide under culture conditions. However, fusarin C was not generated by them in these conditions.

Fusarium graminearum and F. culmorum are phytopathogenic species causing scab and root rot diseases in all small grain cereals worldwide including Turkey. In this study, resistance levels to geneticin (G418) of 14 F. graminearum and 24 F. culmorum isolates collected from cereals were determined. Fungal cultures were grown on potato dextrose agar medium supplemented with 0, 25, 50, 75 and 100 µg/mL of G418. Minimum inhibitory concentration was determined as 25 µg/mL. As a result, it was concluded that all isolates were highly sensitive to G418. Plasmid pFA6-kanmx4 containing geneticin resistance gene (kanmx) was introduced singly or co-electroporated with pEGFP75 plasmid, containing GFP gene, into fungal protoplast cultures obtained with lytic enzyme. Transformants were grown in media including 25 µg/mL G418. Transformation frequencies were 2.8 and 1.8 transformant per µg plasmid for F. graminearum and F. culmorum isolates, respectively. Transformation process was also confirmed by spectrofluorimetric assay. Relative fluorescence unit values in co-transformants were calculated as 1.87 ± 0.04 for F. graminearum and 2.26 ± 0.08 for F. culmorum. The results obtained from the study gave information about antibiotic resistance levels of two Fusarium species in Turkey. Moreover, it was shown that pFA6-kanmx4 plasmid was a suitable vector, which can be used in genetic manipulation studies of these two fungal species in particular suppression of endogenous and/or the expression of exogenous genes.

This study aimed to determine the levels of various polycyclic aromatic hydrocarbon compounds in Mytilus galloprovincialis, seasonally obtained from nine stations in the Istanbul Strait, and their effects on antioxidant enzyme activities. Samples were sorted into two groups based on length as 3–5 cm and 5–7 cm, and all analyses were carried out separately for both groups. Salinity, dissolved oxygen, temperature and pH of sea-water at sampling stations were measured. Very high levels of PAHs were detected, especially in Spring and Summer, hence, the risk of consuming mussels in those seasons was indicated. Mean total PAH was highest in Summer (617,86 ng/g), followed by Spring, Winter and Autumn (536,77 ng/g, 293,34 ng/g, 203,70 ng/g, respectively). The level of Benzo(a)pyrene, potentially the most carcinogenic compound among PAHs, was four times higher than the allowed limits of the European Union. Also, the total level of four PAH compounds (Benzo(a)pyrene, Chrysene, Benz(a)anthracene, Benzo(b)fluoranthene), considered as an indicator of carcinogenic risk, was three times higher than the allowed limits. Catalase, peroxidase and superoxide dismutase enzyme activities were calculated. Mean values of catalase and peroxidase activities were highest in Autumn, followed by Summer, while superoxide dismutase activity was highest in Summer, followed by Autumn. The lowest level of enzyme activity for all three enzymes was in Spring. Positive correlations between enzyme activities and PAH compounds were observed only in Winter and Spring. Catalase was positively correlated with six different PAH compounds, peroxidase with five different and superoxide dismutase with two different PAH compounds. The highest number of negative correlations between enzyme activities and PAH compounds was detected for superoxide dismutase, which was negatively correlated with total PAH and seven different PAH compounds, most of which were observed in Autumn.

Fusarium isolates are divided into three chemotypes according to produce of class B trichothecenes; 3-acetyldeoxynivalenol (3ADON) 15-acetyldeoxynivalenol (15ADON) and nivalenol (NIV) and 4- acetyldeoxynivalenol (NIV) chemotypes. In this study, chemotyping of seventeen isolates from Turkey and Iran belonging to F. graminearum, F. culmorum, F. poae and F. pseudograminearum species were carried out by polymerase chain reaction (PCR) analysis. While all F. culmorum and F. poae isolates determined as 3ADON, remaining F. graminearum and F. pseudograminearum isolates were either 3ADON or 15ADON chemotypes. A common band of 583 bp long DNA fragment was amplified in all of F. culmorum and F. poae, one F. pseudograminearum (21F) and four F. graminearum (14F, sh14, sh15, sh7) isolates with 3ADON chemotype. However, remaining two F. pseudograminearum and four F. graminearum isolates with 15ADON chemotype, yielded amplicons that of 863 bp. It was shown that 3ADON was more predominant chemotype from other class B trichothecenes. This is the first report on chemotyping of F. poae and F. pseudograminearum isolates and also to show presence of 3ADON chemotype in F. graminearum isolate from Turkey.

Five Fusarium graminearum and 12 F. culmorum isolates, primarily pathogenic species of Fusarium head blight, were obtained from naturally infected wheat from various agro-ecological regions of Turkey. Genotyping of the isolates was carried out using random-amplified polymorphic DNA (RAPD). Sixty-five 10-mer oligonucleotide primers were used to amplify the RAPD markers. Among them, 50 primers produced strong and reproducible DNA amplicons. The remaining primers generated either insufficient or no amplification patterns. In total, 1200 fragments were scored, 311 of which were determined to be polymorphic and unique to the isolates. The produced RAPD markers ranged from 0.2 to 5 kb. The mean genetic similarity values of the F. graminearum and F. culmorum isolates were 61.5 and 65%, respectively. The similarity coefficient was 43 to 76.1% among F. graminearum isolates and 49 to 81.1% among F. culmorum isolates. Genetically, the most similar F. graminearum isolates were F6 and F7 (76.1%), which originated from the same agro-ecological region (Sakarya). The most similar F. culmorum isolates were F20 and F21 (81.1%), which were from different geographic regions (Bilecik and UÅŸak, respectively). Moreover, interspecific variation between the two species was determined to be 86.3 to 93.3%. Cluster analysis generated two branched groups, each containing isolates of one species, except F13 of F. culmorum. The sequencing of stable and reproducible monomorphic and polymorphic RAPD markers indicated that the Fusarium genome shared high similarity (105-625 bit scores) with the genomes of other organisms as well as with the F. graminearum reference genome.

Fusarium graminearum and F. culmorum are the major causal agents of Fusarium head blight in Turkey. They produce trichothecenes such as deoxynivalenol (DON), nivalenol (NIV) and their several acetylated derivatives, 3-acetyldeoxynivalenol (3-ADON) and 15-acetyldeoxynivalenol (15-ADON). In this study, a total of thirty-three isolates of F. graminearum and F. culmorum were collected from various regions and three different hosts. They were identified by amplification of tri5 gene cluster. Totally 32 isolates, 21 of F. culmorum and 11 of F. graminearum, were determined as DON chemotype, while only one F. graminearum isolate (1F) was detected as a NIV. A 282 base pair (bp) band for tri13 gene and also ranging from 458 to 535 bp bands for tri7 gene were amplified in all DON producers' genomes. Further analysis of DON chemotype based on tri3 gene amplification showed that all isolates of F. graminearum displayed 15-ADON sub-chemotype. They yielded a 863 bp amplicon. Similarly, 3-ADON sub-chemotype was identified in F. culmorum' isolates except F13. As a result of tri3 gene assay, it was produced a 583 bp fragment in these twenty isolates. It is the first report that a F. graminearum isolate depicts NIV chemotype in agricultural regions of Turkey. According to our findings, DON chemotype is predominating in our country. Also, it is presented that most of the F. graminearum isolates have 15-ADON sub-chemotype, while all F. culmorum's belong to 3-ADON which possess full length amplicon of tri7 gene.

In this study, induction of regenerable callus from mature embryos in eight Turkish barley varieties was analysed by using different plant growth regulators (PGRs). Varying concentrations (0.5-4 mg l -1 ) of 2,4-dichlorophenoxyacetic acid (2,4-D) and dicamba (3,6-dichloro-o-anisic acid) were tested for callus induction from mature embryos. Highest percent of callus induction was observed in Bornova 92 variety (98.3%) on MS medium supplemented with 4 mg l -1 dicamba. Calli were transferred to regeneration media with 0.5 mg l -1 dicamba, 0.5 mg l -1 zeatin riboside (ZR) and 2 mg l -1 thidiazuron (TDZ). Low concentrations of dicamba induced multiple shoots during callus regeneration. When the effect of precultivation with 2,4-D or dicamba on the shoot induction were evaluated, lower concentrations (4 mg l -1 ) of auxins have been found optimal. On the regeneration medium with 0.5 mg l -1 dicamba, shoots were able to elongate up to 20 cm and shoot numbers were between 1-23 per callus. The use of ZR led to formation of short shoot buds and somatic embryos in 2 weeks period. The effect of TDZ was different from other PGRs by inducing green solid sectors on calli surfaces (Total 51 sectors/20 callus/Akhisar variety). Five plantlets have been grown from these solid cell clumps and transferred to specific media for root formation. As a result, five varieties (Süleyman Bey, Bornova 92, Vamyk Hoca, Kaya and Akhisar) tested in our study showed the potential to produce regenerable callus by using low amounts of dicamba or TDZ. The optimization process starts from culturing embryos to plantlet formation took nearly 4 weeks.

In this manuscript, thirty yellow-pigmented Gram-positive bacteria were isolated from natural intestine microflora and from sea water around the marine cage of a rearing tank of common dentex (Dentex dentex), in the Aegean Sea on the Turkish coast and were characterized. Eighteen isolates were assigned to the species Micrococcus luteus, the other twelve to the species Bacillus marisflavi. Eight representative strains, six from B. marisflavi and two from M. luteus, were chosen for further 16S rDNA analyses. A pathogenicity assay for the isolated bacterial strains was carried out in rainbow trout and it evidenced absence of pathogenicity in the tested strains. The isolated strains were tested for in vitro antagonistic activity against Listonella anguillarum, a pathogen bacterium diffused in Mediterranean aquaculture and affecting various fish species. The isolated bacterial strains showed antagonistic activity against the pathogenic bacterium, suggesting a possible role of isolates as probiotics. In this study, for the first time, bacterial strains of the species B. marisflavi, known as an environmental species, were recovered in the gut microbiota of a healthy fish. The use of the isolates characterized in this study, mainly the yellow-pigmented bacterium, is suggested as possible probiotics to improve fish health, along with alternative methods of maintaining a healthy environment.

Reverse transcription polymerase chain reaction (RT-PCR) is a sensitive and powerful method for analyzing RNA. In this study, genes encoding polyphenol oxidase and glucanase enzymes were amplified by using RT-PCR technique in potato and chickpea, respectively. It was also determined that both of the genes were members of multigene family.

In this study, gonadotropin-releasing hormone (GnRH), insulin-like growth factor receptor I (ILGFRI), and androgen receptor (AR) genes coding, were examined by polymerase chain reaction (PCR) analysis and DNA sequencing in three Eurasian sturgeon species: Huso huso, Acipenser stellatus and A. gueldenstaedtii. Amplicons of 190 bp for GnRH, 180 bp for ILGFRI, and 200 bp for AR genes were amplified with specific primer pairs in all species genome. All amplification products were sequenced and compared to reference H. huso genome retrieved from NCBI database by BLASTN analysis. The ILGFRI gene had the most similar sequences (75.96-96.15%) in all species. Gene sequence similarity calculated for AR gene ranged from 48.595.71%. The GnRH gene had more distant sequences (23.48-83.91%) between species. There was moderate similarity between H. huso and the reference H. huso samples. An unauthorized (a sample seized from poachers) sample was more closely related to A. stellatus. Partial coding region of AR gene was registered in NCBI database under Accession Number: KC172108. Five nucleotide changes were detected in this sequence, two of which resulted in changes in amino acid sequence. Also, a partial sequence consisted of two microsatellite regions of two and four nucleotide repeats. Three constructed dendrograms displayed the relationship among species according to certain genomic regions. These findings indicate a high level of diversity among and even within the same species. They also show that these three genes could be useful in species’ identification and characterization. The IJA appears exclusively as a peer-reviewed on-line open-access journal at http://www.siamb.org.il. To read papers free of charge, please register online at registration form. Sale of IJA papers is strictly forbidden.

In this study, we have found differences in chitinase gene expression between sensitive (Red chickpea) and resistant (Flip 91–4C) chickpea (Cicer arietinum L.) genotypes to Ascochyta blight using Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) technique. Total RNAs extracted from leaves of sensitive and resistant genotypes were used for RT-PCR analysis with chitinase gene specific primer (chi) and oligo dT15 primer. Expression of chitinase genes was found to be different in the leaves of sensitive and resistant genotypes using this technique.

The phenotypical, serological, and molecular identification of Vibrio ordalii isolates recovered from diseased gilthead sea bream (Sparus aurata) in the Mediterranean area were investigated. Most isolates had similar phenotypic characteristics, but some showed small differentiation in biochemical analysis. Both slide agglutination and enzyme linked immunosorbent assay (ELISA) showed that the isolates were antigenically homogeneous and no different serotypes were detected. SDS-PAGE analysis showed that the structure of lipopolysaccharide (LPS) was heterogeneous, that outer membrane proteins (OMP) display homogeneous grouping protein banding patterns, and that the LPS profile of the isolates had different banding patterns. However, random amplified polymorphic DNA (RAPD) analysis revealed genetic variation (up to 90.4%) among isolates of the same species.

Albayrak, Gulruh/0000-0002-4499-8912; WOS: 000276491700010 Fusarium culmorum is a pathogen of economically important grain crops. In this work, Rep-PCR was used to identify genetic diversity in F. culmorum isolates which have been collected from wheat fields in Turkey. Reproducible genomic fingerprints were amplified in each strain by PCRs of prokaryotic repetitive extragenic palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC) and BOX sequences. Totally 104 molecular markers were evaluated and similarity comparisons were shown as a dendrogram. The average genetic diversity was 52.3% ranging from 15.8% to 88.7% according to the Rep-PCR data. Cluster analysis showed agreement with the distance of sampling locations. The highest genetic similarity (84.2%) was determined between two F. culmorum isolates (F1 and F2) originated from the same agro-ecological region. Our results showed that Rep-PCR is convenient and rapid for genetic diversity analyses and strain differentiation in F. culmorum. Istanbul UniversityIstanbul University [T-719/30062005] This work was supported by Research Fund of the Istanbul University, project No.T-719/30062005.

Biochemical, pathogenical, antigenical, and molecular characteristics of Vibrio alginolyticus iso- lates from diseased cultured gilthead sea bream juveniles (4 and 20 g) were determined by lab- oratory challenge experiments. Intraperitonal challenge resulted in development of the disease but immersion did not. Electrophoresis of outer membrane protein (OMP) and lipopolysaccha- rides (LPS) was performed using sodium dodecyl sulphate poly-acrylamide gel electrophoresis (SDS-PAGE). Molecular typing of Vibrio isolates was conducted using random amplification of polymorphic DNA (RAPD). According to SDS-PAGE of surface antigens of the isolates, profiles of both OMP and LPS were heterogeneous. According to RAPD, isolated bacteria varied genet- ically. The findings reveal differences among V. alginolyticus isolates from diseased cultured gilt- head sea bream in Turkey.