Fat Utilization and Composition in Germinating Cotton Seeds.

Abstract

Cotton seedlings (Gossyplum hirsutum L.) were grown in solution culture at 30[degree]C in continuous light and in complete darkness. Measurements of the development of the cotyledons, hypocotyls and roots were made. The rate of disappearance and composition of the fat reserve of the cotyledons was determined. Fat utilization was more rapid in the light than in the dark. From 2 through 5 days the rate of depletion of linoleic acid, oleic acid, and the saturated acids followed the equation for a first-order chemical reaction. The iodine value and the percentage of linoleic acid decreased, the percentage of oleic acid increased, and the percentage of saturated fatty acids remained steady during the 1st 4 days and then dropped. Other seedlings were allowed to develop in the dark in temperatures ranging from 21[degree] to 39[degree]C. Under all germination conditions tested, the fat composition was the same function of the total amount of fatty acids remaining in the fat reserve; it was independent of the rate or type of seedling development.