Studies on the Metabolism of Lipids in Plants

Citation

Kurtz, Edwin B. (1952) Studies on the Metabolism of Lipids in Plants. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/RPCV-Y418. https://resolver.caltech.edu/CaltechTHESIS:02062018-154306942

Abstract

This work is concerned with some physiological and biochemical studies of the lipids of higher plants, a subject in which only an extremely limited number of studies have previously been made.

From a study of plants grown under controlled conditions, it was found that both character and amount of fat and wax produced by a plant may be affected by a factor of two or three by day and night temperatures and soil moisture. The effect of increased day or night temperature on the yield of fat was different for different species. Plants generally responded to increased temperature by producing less wax. The fats and waxes from plants at high temperatures were of a higher melting point than those from plants at low temperatures. Water stress plants also produced large amounts of fat, or in Larrea, resin. Although the wax content was only slightly affected by low soil moisture, in Nicotiana glauca an abundant formation of cuticle occurred under this condition. These and other effects of climate on lipids were discussed.

Whereas changes in climate effect up to three-fold changes in lipid yield, a series of recessive genes in corn was found to control ten-fold changes in wax yield. The genetic factors also affect the character and yield of the fats.

A system was obtained for studying the synthesis of fats in a higher plant. Preliminary results show that short chain compounds (ethyl alcohol, acetate, acetone, acetoacetate) may be rapidly utilized in the synthesis of fat. These substrates are readily used only when an energy source such as sugar and the vitamin biotin are supplied. The effects of other substrates and vitamins on fat synthesis were also studied and found to be small or altogether absent.

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