Yazar "Ozer, Goksel" seçeneğine göre listele

Listeleniyor 1 - 8 / 8
  • Küçük Resim Yok
    Öğe
    Characterisation of Cryphonectria hypovirus 1 strains in Turkey and their transmission to various vegetative compatibility types of Cryphonectria parasitica
    (Springer, 2024) Cakar, Deniz; Ozer, Goksel; Simsek, Secil Akilli; Maden, Salih
    Characterization of the Cryphonectria parasitica population was initially done by a phenotypical assessment of 40 in vitro grown isolates obtained from 52 healing cankers collected from eight important chestnut-growing provinces of Turkey. The results of Bavendamm test, often correlated indirectly to hypovirulence, suggested 31 possibly hypovirulent and 9 virulent isolates. PCR tests amplified two regions of ORFs A and B of Cryphonectria hypovirus 1 (CHV-1) from 36 of 40 isolates. The PCR test confirmation was more sensitive than the Bavendamm test. Partial ORFA sequencing revealed 36 CHV-1 haplotypes belonging to Italian subtype (I), with all hypovirulent isolates being of EU-1 vc type. The CHV-1 from 10 native EU-1 isolates were first transferred to six European vc type testers, EU-2, EU-3, EU-5, EU-7, EU-26, and EU-44, having heteroallelism at one vic locus. The presence of the vic locus difference generally reduces virus transmission. The easiest and highest frequency virus transfer was obtained by vic4 and vic6 allelic differences, while the differences vic2 and vic7 made the transfer more challenging. Finally, in this study we successfully transferred CHV-1 to an EU-1 isolate obtained from the Bursa province to an EU-12 European tester isolate.
  • Küçük Resim Yok
    Öğe
    CRISPR/Cas9-mediated Immunity in Plants Against Pathogens
    (Mdpi, 2018) Sameeullah, Muhammad; Khan, Faheem Ahmed; Ozer, Goksel; Aslam, Noreen; Gurel, Ekrem; Waheed, Mohammad Tahir; Karadeniz, Turan
    Global crop production is highly threatened due to pathogen invasion. The huge quantity of pesticides application, although harmful to the environment and human health, is carried out to prevent the crop losses worldwide, every year. Therefore, understanding the molecular mechanisms of pathogenicity and plant resistance against pathogens is important. The resistance against pathogens is regulated by three important phytohormones, viz. salicylic acid (SA), jasmonic acid (JA) and ethylene (ET). Here we review the possible role of CRISPR technology to understand the plant pathogenicity by mutating genes responsible for pathogen invasion or up-regulating the phytohormones genes or resistant genes. Thus hormone biosynthesis genes, receptor and feeding genes of pathogens could be important targets for modifications using CRISPR/Cas9 following multiplexing tool box strategy in order to edit multiple genes simultaneously to produce super plants. Here we put forward our idea that the genes would be either mutated in case of plant receptor protein targets of pathogens or up-regulation of resistant genes or hormone biosynthesis genes will be better choice for resistance against pathogens.
  • Küçük Resim Yok
    Öğe
    Exploring differentially expressed genes in Phaseolus vulgaris L. during BCMV infection
    (Academic Press Ltd- Elsevier Science Ltd, 2024) Yeken, Mehmet Zahit; Celik, Ali; Emiralioglu, Orkun; Ciftci, Vahdettin; Baloch, Faheem Shehzad; Ozer, Goksel
    Bean common mosaic virus (BCMV) is a significant pathogen that affects common bean, leading to substantial yield losses and reduced crop quality. To mitigate BCMV attacks, certain genes, including diacylglycerol kinases genes (PvDGKs), genes associated with defense and stress responses (PvGST, PvPAL, PvLOX, and PvPOD), as well as genes related to plant defense (PvPR1, PvPR2, and PvPR3) play an essential functional role in various stress responses in common bean. In this study, the expression levels of PvDGK1, PvDGK2, PvDGK3, PvDGK5a, PvDGK5b, PvDGK6, PvGST, PvPAL, PvLOX, PvPOD, PvPR1, PvPR2, and PvPR3 genes were investigated in the leaves of different common bean genotypes under BCMV infection conditions. Through quantitative real -time PCR analysis, we observed varying expression patterns for all these genes at different time points during viral infection. The tolerant genotype exhibited higher expression levels of all PvDGKs, PvGST, PvPAL, PvPOD, PvPR1, and PvPR2 genes compared to the susceptible genotype, with the PvPR1 gene showing the highest transcript levels. These findings provide the initial evidence of the potential roles of PvDGKs, PvGST, PvPAL, PvLOX, PvPOD, PvPR1, PvPR2, and PvPR3 in responding to the stress induced by BCMV in common bean. The results presented herein will serve as a valuable resource for guiding future breeding studies aimed at addressing BCMV-induced stress in common bean cultivation.
  • Küçük Resim Yok
    Öğe
    Genetic and pathogenic characterization of Rhizoctonia solani AG-4 isolates obtained from common bean
    (Academic Press Ltd- Elsevier Science Ltd, 2024) Palacioglu, Gulsum; Cankara, Beyza; Bayraktar, Harun; Ozer, Goksel
    Common bean (Phaseolus vulgaris L.) is the most important grain legume. Crop production of common bean is affected by a number of diseases, such as Rhizoctonia root rot, being detected worldwide. Herein, we aimed to genetically and pathologically characterize Rhizoctonia solani isolates obtained from different provinces in Turkey. Anastomosis groups (AG) and subgroups of isolates were identified based on the sequence analysis of the rDNA-ITS region. The most prevalent subgroup was AG-4 HGIII, according to BLAST analysis and the phylogeny of resultant sequences, followed by AG-4 HGI and AG-4 HGII, respectively. iPBS retrotransposons highly supported the phylogenetic tree and provided a high level of genetic variability among isolates to discriminate AG subgroups. The results indicated that the iPBS DNA marker system based on retrotransposons could be used to discriminate Rhizoctonia isolates relying on AG grouping. The virulence of the pathogen isolates changed from 3.67 to 5 based on the agar-plate assay on the susceptible cv. Gina. The reactions of thirty common bean cultivars were also evaluated against the most aggressive isolate in each subgroup. The reaction assay showed significant differences among both isolates and cultivars; the highest disease severity among cultivars was observed to AG-4 HGI, followed by AG-4 HGIII and AG-4 HGII, respectively. None of the cultivars showed resistance to all AG subgroups. Screening of AGs among the isolates and selecting cultivars are critical to managing Rhizoctonia disease due to the range of host suitability according to AG subgroups.
  • Küçük Resim Yok
    Öğe
    Molecular characterisation and efficacy of entomopathogenic fungi against the Green shield bug Palomena prasina (L.) (Hemiptera: Pentatomidae) under laboratory conditions
    (Taylor and Francis Ltd., 2021) Ozdemir, Ismail Oguz; Tuncer, Celal; Ozer, Goksel
    Green shield bug (GSB) Palomena prasina (L.) causes significant yield and quality losses in hazelnut production of Turkey. Alive and dead adults of GSB were collected from the main hazelnut cultivation areas of Turkey during 2018 and 2019. The entomopathogenic fungi (EPF) were isolated from GSB individuals and identified by DNA sequencing of the internal transcribed spacer of the rRNA. Phylogenetic analysis based on the maximum likelihood method of these sequences with reference sequences retrieved from GenBank revealed that 20 native isolates were Beauveria bassiana (6), B. pseudobassiana (1), Cordyceps confragosa (5), Akanthomyces muscarius (4), Purpureocillium lilacinum (2), Isaria fumosorosea (1), and Bionectria sp. (1). Furthermore, the isolates were tested for their efficacy against GSB adults at 1 × 108 spores mL?1 concentration under laboratory conditions. Registered bio-insecticides were applied at the same concentration to compare the efficacy of the isolates. Beauveria spp. isolates were most effective among the tested isolates with LT50 and LT90 values ranging between 3.65–6.14 and 5.26–8.25 days, respectively. These isolates caused 100% mortality in GSB adults within 6–10 days. The isolates of A. muscarius (TR-OR-1) and P. lilacinum (TR-SM-7) were highly effective and caused 100% mortality 10 and 11 days after the treatment, respectively. These results indicated that some EPF isolates obtained in this study are more promising as an alternative control agent against GSB. © 2021 Informa UK Limited, trading as Taylor & Francis Group.
  • Küçük Resim Yok
    Öğe
    Morphological, physiological, molecular, and pathogenic insights into the characterization of Phytophthora polonica from a novel host, hazelnut (Corylus avellana)
    (Academic Press Ltd- Elsevier Science Ltd, 2024) Turkkan, Muharrem; Ozer, Goksel; Dervis, Sibel
    Hazelnuts, constituting a significant global crop, hold paramount importance in Turkiye, contributing to approximately 71.14 % of the world's hazelnut cultivation area. In the summer of 2023, hazelnut trees in two orchards situated in the Altinordu district of Ordu province, within the Black Sea region of Turkiye, the largest producer and exporter of hazelnuts, exhibited symptoms of decline associated with root rot. Phytophthora sp. was consistently isolated from necrotic taproots, initiating an in-depth study to discern the causal agent behind the observed hazelnut decline. The species was identified as P. polonica by its distinctive morphological traits, including homothallic characteristics, amphigynous or paragynous antheridia, long nonbranching sporangiophores, and nonpapillate sporangia with internal proliferation. Multiple genetic markers (ITS, tub2, and COI) facilitated a clear differentiation of P. polonica from other Phytophthora species within Clade 9, supporting its classification within Subclade 9b. This investigation also evaluated the impact of diverse nutrient media (CA, V8A, and CMA), temperatures, and pH levels on the mycelial growth of P. polonica HPp-1 and HPp-2 isolates. The optimal conditions for maximal mycelial growth were determined through the D-optimal design of the Response Surface Method, revealing the significant influence of all factors on mycelial growth. The identified optimal conditions were at 26.09 degrees C, pH 5.12, with CMA as the nutrient medium. Validation experiments conducted under these optimal conditions unveiled mycelial growth of 7.24 +/- 0.15 mm day(-1) and 6.81 +/- 0.09 mm day(-1) for P. polonica HPp-1 and HPp-2 isolates, respectively, with an error of less than 5 %. Pathogenicity assessments confirmed P. polonica's virulence on hazelnuts, with distinct lesion development observed in twig inoculation, cut stem segments, and foliar tests. While no statistically significant difference was noted in lesion areas between HPp-1 and HPp-2 isolates in twig and stem segment assays, a statistical difference in leaf lesion areas (19.96 +/- 2.04 cm(2) and 9.16 +/- 3.43 cm(2)) emerged in foliar tests after only a 5-day incubation period, indicating their high susceptibility to the pathogen. This study is the first to report P. polonica as a hazelnut pathogen in Turkiye and around the world, highlighting the previously non-existent threat of Phytophthora root rot in hazelnuts, given the substantial lack of scientifically documented cases related to hazelnut root rot diseases. The quadratic model design employed in physiological analyses is reliable for optimizing mycelial growth and can serve as a guiding framework for similar investigations.
  • Küçük Resim Yok
    Öğe
    Neoscytalidium dimidiatum: A newly identified postharvest pathogen of pears and its implications for pome fruits
    (Wiley, 2024) Dervis, Sibel; Zholdoshbekova, Sezim; Guney, Inci Guler; Ozer, Goksel
    T & uuml;rkiye is a prominent contributor to pear and diverse pome fruit production. Pear fruit with unusual brown to black spots and rot symptoms observed in public marketplaces in Mardin province have raised concerns regarding postharvest fruit health. The consistent isolation of a fungus from these fruits revealed morphological features indicative of Neoscytalidium dimidiatum. Phylogenetic confirmation of its identity ensued through BLASTn searches targeting, the internal transcribed spacer (ITS) of ribosomal DNA, the partial translation elongation factor 1-alpha gene (tef1), and the partial beta-tubulin gene (tub2). Pathogenicity evaluations were conducted on common pome fruits, namely pears, apples, and quinces, unveiling the susceptibility of all examined fruits to postharvest infection by this emergent pathogen. Furthermore, an investigation was carried out to discern the pathogen's response to varying temperature ranges on pear fruits, revealing that the most pronounced lesions occurred at 30 degrees C, followed by 25 degrees C, 35 degrees C, and 20 degrees C. Conversely, no lesion development was observed at 10 degrees C, 15 degrees C, or 40 degrees C. To the best of our knowledge, this study represents the first report of N. dimidiatum as the etiological agent responsible for postharvest rot in pear fruit. The implications of these findings highlight the potential threat posed by this pathogen to pome fruits postharvest, especially in regions where cold storage facilities are not widely utilized, warranting increased vigilance and preventive measures.
  • Küçük Resim Yok
    Öğe
    New Detection Methods for Cryphonectria Hypovirus 1 (CHV1) through SYBR Green-Based Real-Time PCR and Loop-Mediated Isothermal Amplification (LAMP)
    (Mdpi, 2024) Celik, Ali; Cakar, Deniz; Dervis, Sibel; Morca, Ali Ferhan; Simsek, Secil Akilli; Romon-Ochoa, Pedro; Ozer, Goksel
    Some mycoviruses can be considered as effective biocontrol agents, mitigating the impact of phytopathogenic fungi and consequently reducing disease outbreaks while promoting plant health. Cryphonectria parasitica, the causal agent of chestnut blight and a highly destructive pathogen, experienced a notable decrease in its virulence with the identification of cryphonectria hypovirus 1 (CHV1), a naturally occurring biocontrol agent. In this study, two innovative diagnostic protocols designed for the accurate and efficient detection of CHV1 are introduced. The ORF A and ORF B regions of CHV1 are targeted by these techniques, which employ colorimetric loop-mediated isothermal amplification (LAMP) with 2 Colorimetric LAMP Master Mix and real-time quantitative PCR (qPCR) with SYBR Green chemistry, respectively. The LAMP assay presents a discernible color transition, changing from pink to yellow after a 35 min incubation period. Comparative analysis, when assessed against two established reverse transcription-PCR (RT-PCR) techniques, reveals a significant enhancement in sensitivity for both the LAMP approach, which offers a tenfold increase, and the qPCR method, which showcases a remarkable 100-fold sensitivity improvement. Throughout the comparison phase, it was evident that the RT-PCR, LAMP, and qPCR procedures displayed superior performance compared to the Bavendamm test, relying on phenol oxidase activity, effectively distinguishing hypovirulent strains. Consequently, this study introduces two pioneer diagnostic assays for highly sensitive CHV1 detection, representing a substantial advancement in the realm of CHV1 surveillance techniques. These methodologies hold significant promise for enhancing research endeavors in the domain of the biological control of C. parasitica.