Are changes in membrane lipids and fatty acid composition related to salt‐stress resistance in wild and cultivated barley?. Issue 2 (27th March 2013)

• Record Type: Journal Article
• Authors: Chalbi, Najla; Hessini, Kamel; Gandour, Mhemmed; Mohamed, Salma Naeit; Smaoui, Abderrazek; Abdelly, Chedly; Youssef, Nabil Ben
• Is Part Of: Journal of plant nutrition and soil science. Volume 176:Issue 2(2013:Apr.)
• Page Start: 138
• Page End: 147
• Publication Date: 2013-03-27
• Subjects: Plants -- Nutrition -- Periodicals; Soil science -- Periodicals; 630
• DOI: 10.1002/jpln.201100413
• Languages: English
• ISSNs: 1436-8730

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The possibility to use membrane‐lipid measurements to screen barley genotypes for salt resistance was studied. The results showed that wild barley (<italic>Hordeum maritimum</italic>) displayed a typical halophytic response as compared to cultivated barley (<italic>Hordeum vulgare</italic> L. cv. Manel). Growth, tissue hydration, and photosynthetic activity were less affected by salinity in <italic>H. maritimum</italic> than in <italic>H. vulgare.</italic> The induced effects of long‐term NaCl treatment were reflected in root membrane lipids that remained relatively unchanged in wild barley, whilst they were significantly diminished with increasing salinity in <italic>H. vulgare.</italic> The levels of membrane‐lipid peroxidation and electrolyte leakage were changed only at high salt concentrations in <italic>H. maritimum</italic> whereas those of <italic>H. vulgare</italic> were considerably increased by lower salinity levels as a result of oxidative damage. These findings indicate that maintained membrane integrity (in <italic>H. Maritimum</italic>) may be considered a possible trait for salt resistance. However, membrane fluidity in <italic>H. vulgare</italic> was more increased than in <italic>H. maritimum.</italic> Thus, the unsaturated–to–saturated fatty acid ratio (UFAs : SFAs) and the double‐bond index (DBI), significantly increased in response to salt stress in cultivated barley while it did not change in <italic>H. maritimum.</italic> The changes in lipid unsaturation were predominantly due to increases in linolenic (C<sub>18:3</sub>), linoleic (C<sub>18:2</sub>), and oleic (C<sub>18:1</sub>) acids and decreases in stearic acid (C<sub>18:0</sub>). These results suggest that, in spite of being important for maintenance of membrane fluidity, the ability to increase unsaturation is not a determinant factor for salt resistance in barley species.</p> </abstract>