THE RELATION OF THE CHARACTERISTICS AND YIELD OF WAX TO PLANT AGE

Abstract

Young and old leaves and stems of 11 spp. native to Arizona, and several ages of leaves of Phoenix dactylifera and Sorghum halepense, were studied. The waxes were separated from the petroleum ether plant extract as an acetone-insoluble fraction. The yields and characteristics (m.p., iodine no., acid no., saponification no.) of the wax and non-wax fractions were detd. The yield of wax varied directly with cuticle thickness and generally increased with plant age. The wax m.p. increased with age as a result of increased saturation. The inter-relationships as a function of age of wax and non-wax acid and ester content are discussed. The cellular fatty acids appear to be used in the formation of fatty esters and wax acids. No relationship was found between carbohydrate and lipid content of the leaves. The results of one dioecious species indicate that sex may have a strong influence upon plant lipid metabolism.