Changes in Fatty acids of alfalfa roots during cold hardening.

The fatty acid composition of nonhardy Caliverde and hardy Vernal alfalfa roots as a function of the hardening process was determined by gas-liquid chromatography.The fatty acid contents of nonhardy Caliverde and hardy Vernal alfalfa root tissue increased approximately 2-fold during hardening. This increase was associated with hardening but could not be used to distinguish between varieties. The fatty acid composition of the alfalfa root changed during hardening due to the preferential accumulation of polyunsaturated fatty acids. The preferential deposition of linoleic and linolenic fatty acids caused an increase in the average number of unsaturated bonds in the fatty acids. Apparently, lipid metabolism of the roots was altered during hardening.