Effect of cold stress on antioxidant mechanism of winter and spring type barley (hordeum vulgare L.) cultivars

Afşar, Nilüfer
In this study, effect of cold stress on physiology and biochemistry of two Turkish barley cultivars, winter type Tarm-92 and spring type Zafer-160, was studied. For chilling stress treatment, cultivars were exposed to +4 ºC for 1, 3 and 7 days, and for freezing stress application acclimated cultivars (+4 ºC for 3 days) were treated with -3 ºC and -7 ºC. After freezing stress treatment, a recovery period was applied for 4 days at 4 ºC. Following analyses were performed on leaf and root tissues: growth parameters (length, wet-dry weights), malondialdehyde (MDA) content, proline content, hydrogen peroxide content (H2O2) electrolyte leakage, PS II fluorescence (Fv/Fm), antioxidant enzyme activities such as catalase (CAT: EC, ascorbate peroxidase (APX: EC and glutathione reductase (GR: EC It was observed that effect of cold was more at freezing temperatures than chilling temperature. Cold dependent damage was more obvious as the duration of chilling temperature increased. Growth retardation, membrane damage, leaf catalase deactivation were more apparent and leaf glutathione reductase activity increase was less in spring type cultivar Zafer than in winter type Tarm. These results indicated that winter type barley cultivar is more cold tolerant than spring type barley.


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Interactions of simvastatin with zwitterionic dipalmitoyl phosphotidylcholine (DPPC) multilamellar liposomes were investigated as a function of temperature and simvastatin concentration. And acyl chain length effect on the simvastatin-model membrane interactions was monitored with DPPC and dimyristoyl phosphotidylcholine (DMPC) lipids. All studies were carried out by two non-invasive techniques, namely Fourier transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). The results s...
Effects of Formaldehyde Inhalation on Zinc, Copper and Iron Concentrations in Liver and Kidney of Male Rats
ÖZEN, OĞUZ ASLAN; KUŞ, İLTER; Bakirdere, Sezgin; Sarsilmaz, Mustafa; YAMAN, MEHMET (Springer Science and Business Media LLC, 2011-05-01)
In the present study, adult Wistar albino male rats were exposed to formaldehyde at different periods (subacute and subchronic) and concentrations (5.0 and 10.0 ppm) in order to figure out the changes in the concentration of Zn, Cu and Fe. It was observed that the formaldehyde inhalation caused gradual decline of body weights in the experimental groups when compared with control groups. It was found that subacute (4-week) or subchronic (13-week) exposure to formaldehyde for rats may cause growth retardation...
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TURKOGLU, S; OZER, I (Elsevier BV, 1992-06-01)
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The purpose of this study was to observe the effects of different starvation conditions on the surface characteristics and adhesive properties of bacteria. Three pure culture xenobiotic degrading bacteria were used in this study: Pseudomonas sp. strain A, Pseudomonas sp. strain D and Rhodococcus corallinus strain 11. These microorganisms were selected for to their ability to degrade cyanuric acid, which is a derivative of s-Triazine, a common herbicide. These microorganisms were separately starved for carbo...
Citation Formats
N. Afşar, “Effect of cold stress on antioxidant mechanism of winter and spring type barley (hordeum vulgare L.) cultivars,” M.S. - Master of Science, Middle East Technical University, 2007.