Changes in the fatty acid unsaturation after hardening in wheat chromosome substitution lines with different cold tolerance

Two wheat (Triticum aestivum L.) varieties, Cheyenne (Ch, winter wheat with excellent frost tolerance) and Chinese Spring (CS, spring wheat with weak frost tolerance), and chromosome substitution lines (CS/Ch 5A, CS/Ch 5D, CS/Ch 7A) created from Cheyenne and Chinese Spring were used to study the effect of chromosome substitutions on the membrane lipid composition in the leaves and crowns before and after cold hardening. The percentage of fatty acid unsaturation in phosphatidylethanolamine was greater in the crown of hardened Cheyenne than in Chinese Spring. The value of CS/Ch 5A was similar to Cheyenne and that of CS/Ch 5D to Chinese Spring, while the value of CS/Ch 7A was in between those of Cheyenne and Chinese Spring. A smaller difference was found between the unsaturation level in the phosphatidylcholine from Cheyenne and Chinese Spring after hardening, while the value obtained for the substitution line CS/Ch 7A was similar to Cheyenne. The percentage decrease in thetrans-Δ3-hexadecenoic acid content was found to be correlated with the frost tolerance of the wheat genotypes.