Effect of NaCl and Polyamines on Plasma Membrane Lipids of Wheat Roots

Caryopses of a salt sensitive wheat cultivar (Triticum aestivum L. cv. Giza 163) were presoaked in 2.5 mM putrescine (Put), 5 mM spermidine (Spd) or 2.5 mM spermine (Spm) for 24 h and then subjected to 150 mM NaCl added to the growth medium for 15 d. Effects of NaCl and polyamines (PAs) on plasma membrane (PM) lipids, phospholipids, fatty acids, and free sterols were determined. NaCl treatment caused a decrease in total phospholipids, increase in saturated fatty acids and altered distribution of sterols and phospholipids. NaCl also induced increase in sterol/phospholipid ratio. PAs treatments (particularly Put and Spd) counterbalanced the NaCl deleterious effects on PM lipids.