Lipid changes in winter wheat seedlings (Triticum aestivum) at temperatures inducing cold hardiness

Abstract

The changes in total lipid, fatty acid, and lipid phosphorus contents were followed during germination and early growth of Rideau wheat seedlings at 24° for 72 h and 2° for 5 weeks. At both temperatures the changes in total lipids and total fatty acids were similar for seedlings at comparable stages of morphological development. In contrast, the phospholipid content of seedlings grown at 2° was considerably higher than that of seedlings grown at 24°. A marked increase in linolenic acid was also observed during growth at 2°, and this change occurred entirely in the embryo. The results indicate an increased synthesis and unsaturation of membranes in seedlings grown at 2°. The changes may contribute to the increased resistance to freezing temperatures exhibited by seedlings grown at 2°.