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    Benchmarking of the Effects of Salinity on Antioxidant Enzymes Activities, Lipid Peroxidation and H2O2 Levels in the Leaves of Two Zinnia Species
    (Kahramanmaras Sutcu Imam Univ Rektorlugu, 2021) Yasemin, Sara; Deger, Aysin Guzel; Cevik, Sertan; Koksal, Nezihe
    In this study, it was aimed to investigate the effects of salinity, which is an important environmental problem, in the cultivation of ornamental plants (such as zinnia) and irrigation with high salt water, especially on the antioxidant defense mechanism. For this purpose, the two Zinnia species were irrigated by different concentrations of saline water (50, 100, 150, 200 mM NaCl); effects of salinity on superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) lipid peroxidation (MDA) and hydrogen peroxide (H2O2) in the leaves were determined. The results showed that salinity conspicuously increased SOD, CAT, GR, H2O2 and MDA content at two Zinnia species compared to the control groups. It was found that SOD and CAT enzyme activities increased remarkably with 150 mM NaCl in both Zinnia species, but decreased with 200 mM NaCl.The highest GR enzyme activity was observed in 200 mM salt concentration at Zinnia marylandica 'Double Zahara Fire Improved'. MDA and H2O2 levels were observed higher in Zinnia elegans 'Zinnita Scarlet'.To conclude; it may be said that these two Zinnia varieties can tolerate salt concentration up to 150 mM.
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    Öğe
    Comparative Analysis of Morphological, Physiological, Anatomic and Biochemical Responses in Relatively Sensitive Zinnia elegans 'Zinnita Scarlet' and Relatively Tolerant Zinnia marylandica 'Double Zahara Fire Improved' under Saline Conditions
    (Mdpi, 2023) Yasemin, Sara; Koksal, Nezihe
    Salinity is one of the major abiotic stresses in plants. The aim of the present study was to determine the effects of salinity on relatively sensitive Zinnia elegans Jacq. 'Zinnita Scarlet' and relatively tolerant Zinnia marylandica D.M. Spooner et al. 'Double Zahara Fire Improved' through a comparative analysis of morphological, physiological, anatomic, and biochemical traits. Plants were irrigated at five levels of salt concentrations (0 [control], 50, 100, 150, 200 mM NaCl) for three weeks at one-day intervals in pots under greenhouse conditions. The effects of salinity stress on plant growth parameters, ion leakage, the loss of turgidity, minimum fluorescence (F-O'), plant nutrient elements, leaf anatomic parameters, stoma response to the application of light and abscisic acid perfusion, proline content, chlorophyll a, b and total chlorophyll, and carotenoid content were investigated. Differences in the stages and levels of plant response in the relatively sensitive and relatively tolerant cultivar were determined. Proline accumulation appeared to be higher in Double Zahara Fire Improved (D.Za.F.I.) than Zinnita Scarlet (Zi.S.) in the low concentration of salinity. After the application of abscsic acid perfusion to intact leaf surfaces, the stomata of the relatively tolerant cultivar D.Za.F.I. closed earlier (7 min) than Zi.S. (29 min). Ion leakage (32.3%) and Na accumulation (0.9%) in the aerial parts increased dramatically for Zi.S in the 50 mM NaCl treatment. Moreover, values of plant growth parameters, minimum fluorescence (F-O'), photosynthetic pigments, and plant nutrient elements all showed a greater decreasing percentage in Zi.S. compared to D.Za.F.I. Stomatal densities for both the abaxial and adaxial surfaces of the leaf decreased in parallel with the increase in salt stress. Palisade parenchyma cell height and leaf thickness values decreased in Zi.S. as salinity increased. In D.Za.F.I., leaf thickness increased by up to 100 mM NaCl while the height of palisade parenchyma cells decreased under high salt stress conditions (100 mM and above). Recommendations for future research include molecular-level evaluations and the study of how to increase salt tolerance in these potentially valuable ornamental cultivars.
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    Öğe
    Indirect organogenesis and in vitro bulb formation of Pancratium maritimum
    (Springer, 2023) Yasemin, Sara; Koksal, Nezihe; Buyukalaca, Saadet
    Sea daffodil (Pancratium maritimum L.), which belongs to the Amaryllidaceae family, grows in sandy areas along coastal regions and its population is at risk due to the exploitation of its natural resources for medicinal purposes, tourism, and urbanization. Micropropagation is employed to conserve and sustain endangered plant species like P. maritimum. In this investigation, different types of explants (leaf, root, and mature zygotic embryos) from P. maritimum were cultured on Murashige-Skoog (MS) medium supplemented with 2,4-Dichlorophenoxyacetic acid (2,4-D) (1, 2, 4 mg l(-1)) and 6-Benzyladenine (BA) (0 and 1 mg l(-1)) for callus induction. The callus formation rate, callus growth rate, embryogenic callus rate, and callus type were evaluated. The induced calli were further tested for shoot formation on MS medium supplemented with 2 mg l(-1) BA and 0.2 and 0.5 mg l(-1) 2,4-D. The results showed that the highest callus induction was achieved using zygotic embryo explants and the medium containing both 2,4-D and BA. Successful shoot formation from callus was determined using both MS media supplemented with 2 mg l(-1) BA and 0.5 or 0.2 mg l(-1) 2,4-D, with a success rate of 90%. To induce in vitro bulb formation of P. maritimum plantlets, MS medium containing varying concentrations of sucrose (20, 40, and 80 g l(-1)), BA (0, 1, and 2 mg l(-1)), and 2,4-D (0, 0.1, and 0.2 mg l(-1)) was utilized. The bulb formation rate of P. maritimum was successful in all growth media, ranging from 60 to 82%. The diameter of the bulb was found to increase with higher sucrose concentration (80 g l(-1)) in the growth medium. The impact of plant growth regulators on bulb weight was more pronounced in nutrient medium containing low sucrose concentration (20 g l(-1)). Efficient protocols for embryogenic callus induction, organogenesis, regeneration, bulb formation, and acclimatization were developed for P. maritimum, providing valuable insights for future studies. Key messagePancratium maritimum is an endangered plant with medicinal and decorative value. We have successfully developed a comprehensive protocol for its micropropagation, including callus induction, regeneration, bulb formation, and acclimatization.