Membrane Lipid Changes During Cold Acclimation of Spring Rape

Abstract

Summary Brassica napus L. (spring rape) is capable of a moderate degree of cold acclimation. An increase in the content of complex lipids and lipid phosphorus during cold acclimation indicates membrane augmentation, and a decrease in lipid galactose during cold acclimation suggests a qualitative membrane change. In the complex lipid fraction the fatty acids 16 : 0, 18 : 1 and 18 : 2 increased, and the fatty acids 16 : 2 and 18 : 3 decreased. The mole percent unsaturation of the fatty acids decreased slightly during cold acclimation. Thus fatty acid unsaturation is not directly related to the cold hardiness increase that occurs during cold acclimation. Spring rape is similar to hardy trees in that the unsaturated fatty acid content does not increase during cold acclimation; therefore, of the herbaceous plants studied to date, spring rape is unique.