1,720,996 research outputs found
Stochasticity in transcriptional expression of a negative regulator of Arabidopsis ABA network
No full textPEHLIVAN, NECLA/0000-0002-2045-8380Stably heritable spatiotemporal co/over-expression of distinct transcriptional regulators across generations is a desired target as they signal traffic in the cell. Here, the stability and expression pattern of AtHB7 (Arabidopsis homeodomain-leucine zipper class I) cDNA was characterized in 220 random population of transformed tomato clones where no AtHB7 orthologous has been identified in to date. Integration of p35
Salt stress relief potency of whortleberry extract biopriming in maize
No full textPEHLIVAN, NECLA/0000-0002-2045-8380Berries have gained public attention for their presumed positive effects on cancer patients. in contrast, the potential of berries to mitigate damage caused by abiotic stress in plants has not received significant attention. This is the first quantitative analysis of the efficacy of Vaccinium arctostaphylos L. (Ericaceae) fruit extract (VAFE) used to bioprime maize to limit damage caused by salt stress. Salt stressed maize seedlings exhibit lower quantum efficiency of photosystem II (Fv/Fm) and photosynthetic pigment content relative to untreated controls however, Fv/Fm increase caused by VAFE was found marginal. VAFE biopriming limited pigment loss and increased levels of antioxidant enzymes. It improved the growth of salt stressed seedlings by reducing salt-induced biomass loss, damage to roots and shoots, lipid oxidation, proline synthesis and endogenous hydrogen peroxide concentrations. in sum, VAFE biopriming may provide a new approach to improve yields in soils containing high salt levels as an alternative to traditional agricultural practice.Recep Tayyip Erdogan UniversityRecep Tayyip Erdogan University [FBA-2017-673]I acknowledge Dr. Vagif Atamov for the authentication of the Vaccinium arctostaphylos L. (Ericaceae) and Dr. Serdar Ulker for providing the extract. I am also grateful to Michael L. Mishkind, Neslihan S. Guler and Muhammed Yesilyurt for their valuable help. This study was supported by the research fund of Recep Tayyip Erdogan University, project No: FBA-2017-673
Protective effect of a natural ally on simultaneous mild heat and salt episodes in maize seedlings
No full textPEHLIVAN, NECLA/0000-0002-2045-8380Abiotic stresses occur together in several combinations in nature and do not usually act alone. However, studies on plants mainly are limited to a single stress type. Yet, atmospheric trends make it indispensable to expand approaches to investigate physiological consequences under multiple abiotic stresses. the potential of Melatonin (Mel) hydropriming on photosynthetic machinery and antioxidant system was investigated in this study. Mel hydropriming (0.1mmol/mL) resulted in leaf photochemistry protection, which is characterized by maximum photochemical efficiency of PSII, photosynthetic pigments intactness, reactive oxygen species (ROS) scavenging enzymes activation accompanying depressed levels of endogenous hydrogen peroxide (H2O2) and membrane oxidation in maize seedlings at early vegetative stage under combination of 150mM NaCl and 37 +/- 3 degrees C mild heat. Mimicking nature by combining stresses is more realistic to study abiotic stress responses. High antioxidant capacity of melatonin can serve as a hydropriming substance to withstand simultaneous heat and salt stress.Research Fund of Recep Tayyip Erdogan UniversityRecep Tayyip Erdogan University [645]This work was conducted with the grant provided by the Research Fund of Recep Tayyip Erdogan University (Project ID: 645)
Evaluation of genetic diversity of cultivated tea clones (Camellia sinensis (L.) Kuntze) in the eastern black sea coast by inter-simple sequence repeats (ISSRS)
Full text linkSANDALLI, Cemal/0000-0002-1298-3687; PEHLIVAN, NECLA/0000-0002-2045-8380Tea is the most globally consumed drink after spring water and an important breeding plant with high economical value in Turkey. in half a century, various kinds of tea cultivars have been bred in Turkey to improve the quality and yield of tea plants. Since tea reproduces sexually, tea fields vary in quality. Thus, determining the genetic diversity and relationship of the plants to support breeding and cultivation is important. in this study we aimed to determine the genetic diversity of tea cultivars breeding in the Eastern Black Sea coast of Turkey and the genetic relationship between them, to verify whether the qualitative morphological designations of the clones are genetically true by the ISSR markers. Herein, the genetic diversity and relationships of 18 Turkish tea cultivars were determined using 15 ISSR markers with sizes ranging from 250 to 3000 base pairs. the similarity indices among these cultivars were between 0.456 and 0.743. Based on cluster analysis using UPGMA, some of tea cultivars originating from the same geographical position were found to be clustered closely. Our data provide valuable information and a useful basis to assist selection and cloning experiments of tea cultivars and also help farmers to find elite parental clones for tea breeding in the Eastern Black Sea coast of Turkey.Recep Tayyip Erdogan UniversityRecep Tayyip Erdogan University [BAP_2013.102.03.4]This work was supported by Recep Tayyip Erdogan University Research Fund Grants BAP_2013.102.03.4
Co-overexpressing a plasma membrane and a vacuolar membrane sodium/proton antiporter significantly improves salt tolerance in transgenic arabidopsis plants
Full text linkKADIOGLU, Asim/0000-0002-4781-6264; PEHLIVAN, NECLA/0000-0002-2045-8380The Arabidopsis gene AtNHX1 encodes a vacuolar membranebound sodium/proton (Na+/H+) antiporter that transports Na+ into the vacuole and exports H+ into the cytoplasm. the Arabidopsis gene SOS1 encodes a plasma membranebound Na+/H+ antiporter that exports Na + to the extracellular space and imports H + into the plant cell. Plants rely on these enzymes either to keep Na + out of the cell or to sequester Na + into vacuoles to avoid the toxic level of Na + in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration > 200mM would kill AtNHX1-overexpressing or SOS1-overexpressing plants. Here it is shown that co-overexpressing AtNHX1 and SOS1 could further improve salt tolerance in transgenic Arabidopsis plants, making transgenic Arabidopsis able to tolerate up to 250mM NaCl treatment. Furthermore, co-overexpression of AtNHX1 and SOS1 could significantly reduce yield loss caused by the combined stresses of heat and salt, confirming the hypothesis that stacked overexpression of two genes could substantially improve tolerance against multiple stresses. This research serves as a proof of concept for improving salt tolerance in other plants including crops.Howard Hughes Medical InstituteHoward Hughes Medical InstituteThis research was supported by a Howard Hughes Medical Institute grant through the Undergraduate Science Education Program to Texas Tech University
Trichoderma atroviride ID20G inoculation ameliorates drought stress-induced damages by improving antioxidant defence in maize seedlings
No full textPEHLIVAN, NECLA/0000-0002-2045-8380; BOZDEVECI, ARIF/0000-0002-0729-9143Maize is an agro-economically important crop and its global scale cultivation dates back to ancient times. It is vital to find organic solutions for the agricultural sustainability of maize. Trichoderma spp. is a cheap bio-control candidate having favorable effects on plant growth and enhances resistance to abiotic stresses. Herein, the effect of the endophytic fungus Trichoderma atroviride, our local isolate named ID20G (TaID20G), was evaluated in maize (Zea mays L.) seedlings under drought stress. the fungal strain was characterized based on the internal transcribed spacer (ITS) sequence of 5.8S rDNA. Relative water content, phenotypic characters of roots, antioxidant enzyme activity, hydrogen peroxide content, lipid peroxidation and chlorophyll fluorescence (Fv/Fm ratio) were recorded. Root colonization of TaID20G increased fresh and dry weight of maize roots under drought stress. Chlorophyll and carotenoid contents of seedlings were reduced by drought stress and membrane damage was high in uninoculated plants. Root colonization of TaID20G almost totally prevented increase in lipid peroxidation and reversed the changes caused by drought in pigment contents and photosystem efficiency. Antioxidant enzyme activity was induced and hydrogen peroxide (H2O2) content was less in response to drought stress in inoculated plants. Taken together, these data indicate that TaID20G inoculation could diminish the injurious effects of drought and might have a function in arranging resilience against stress by inducing antioxidant machinery. Low cost and effortless nature of Trichoderma-based formulas might be developed as crop protectors in drought-affected lands around the world, leading to an eco-friendly insight into the plant stress tolerance
Salt stress resilience potential of a fungal inoculant isolated from tea cultivation area in maize
No full textPEHLIVAN, NECLA/0000-0002-2045-8380Agriculture needs to be sustained by organic processes in current era as population explosion energy and the number of individuals undernourished are raising public concerns. Global warming poses additional threat by lifting the damage of salt stress especially in agro-economically vital crops like maize whose cultivation dates back to Mayans. To that end, cost-effective and organic fungal agents may be great candidates in stress resilience. We isolated the fungal strain from the soil of tea plants and characterized that via 5.8 S rDNA gene with internal transcribed spacer ITS-1 and ITS-2 regions, then named the target strain as TA. Reduced maximum quantum efficiency of PS II (Fv/Fm), the effective quantum yield of PS2 (Phi FPS2), electron transport rate (ETR), photochemical quenching (qP) and increased non-photochemical quenching (NPQ) were detected in maize plants stressed with dose dependent salt. Enhanced Fv/Fm, Phi FPS2, ETR, qP and decreased NPQ was observed in TA primed plus NaCl treated plants. TA biopriming significantly increased the lengths, fresh and dry weights of root/shoots and decreased the lipid peroxidation. Maize seedlings bioprimed with TA had less MDA and higher soluble protein, proline, total chlorophyll, carotenoid and RWC under NaCl. Furthermore, SOD, GPX and GR activities were much more increased in root and leaves of TA primed seedlings, however CAT activity did not significantly change. This is the first report to our knowledge that TA reverses the damage of NaCl stress on maize growth through improving water status, antioxidant machinery and especially photosynthetic capacity.Research Fund of Recep Tayyip Erdogan UniversityRecep Tayyip Erdogan University [2012.102.03.3, 2015.53001.102.03.07]This work was supported by the Research Fund of Recep Tayyip Erdogan University (project numbers: 2012.102.03.3 and 2015.53001.102.03.07)
Trichoderma lixii ID11D seed biopriming mitigates dose dependent salt toxicity in maize
No full textPEHLIVAN, NECLA/0000-0002-2045-8380Certain number of commercial products has been developed to grow stress resistant plants for the sustainability of agriculture in current era with full of energy dependency and hunger besides global warming. Given the risk of these products on the microbial environment in the rhizosphere and food security of mankind due to the accumulated chemical pollution through the food web, organic fungal plant growth promoting agents might be used. Hence, effects of Trichoderma lixii ID11D (TXD), our local fungal isolate on Zea mays L. cv. Samada 07 as a seed biopriming agent was investigated under dose dependent NaCl stress in this study. Fungus was characterized based on ITS (internal transcribed spacer) regions via clustering approach after isolated from tea plantation area. the higher the NaCl concentration, the more effective the TXD was observed. Improved electron transport rate (ETR), maximum quantum efficiency of PS II (Fv/Fm), the effective quantum yield of PS2 (Phi PS2), photochemical quenching (qP) and decreased non-photochemical quenching (NPQ) was detected in TXD primed plants after NaCl expose. TXD seed biopriming increased the lengths, fresh and dry weights of root/shoots and decreased the lipid peroxidation (MDA) remarkably. Non-enzymatic pathway was found to be more effective than enzymatic one for seed bioprimed plants proven by higher RWC, soluble protein, proline, chlorophyll, carotenoid, and less H2O2 and MDA levels under each dose of NaCl. Detected phenotypic and biochemical improvements pave the way of the potential usage of the formulated fungus biopreperations as a pre-harvest agent in agriculturally important cereals in the future and going beyond lab-based level.Recep Tayyip Erdogan University Research FundRecep Tayyip Erdogan University [2012.102.03.3, 2015.53001.102.03.07]This work was financed by the Recep Tayyip Erdogan University Research Fund (Project Numbers: 2012.102.03.3 and 2015.53001.102.03.07). We thank PhD candidate Sule Guzel for her valuable help
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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