Effect of Gibberillic Acid and Cycocel on Majorana Hortensis Mnch1 II. The essential oil

Abstract

Two growth regulators GA and CCC were used in this experiment to study their effect on sweet marjoram plants. The concentrations, used were 25, 50, and 100 ppm for GA and 500, 1,000, 1,500. 2,000 and 4.000 for CCC. The study of the effect of the growth regulators comprised the total fresh weight, the fresh weight of the plant organs, the total dry weight, the dry weight of the plant organs, percentage of essential oil in fresh plant organs, percentage of essential oil in dry plant organsand the physical and chemical properties of fresh leaves and racemes essential oils.
The results of the study showed that the total fresh weight was significantly increased with GA treatments, while it was significantly decreased with CCC treatments. The same result was obtained with the fresh weight of the plant organs except that the racemes were not affected. The total dry weight of the plant as well as that of the plant organs were higher in GA treatments than the control and CCC treatments in all cases. Percentage of essential oil of fresh plant organs was higher in GA 25 ppm and CCC 1500 ppm than the other treatments while in GA 100 ppm it was the lowest. No essential oil was found in the stems. Percentage of essential oil of dry plant organs was almost the same in all treatments. Physical and chemical properties of leaves and raceme oil were almost similar to those reported except the ester number of the raceme oil which was found to be higher than that of the leaf oil.