INHIBITORY EFFECT OF EMPTY PALM FRUIT BUNCHES’ BIO-OILS AGAINST SEED GERMINATION AND SEEDLING GROWTH OF THREE SELECTED SEEDS

Abstract

In a search for effective methods for controlling seed germination and growth, bio-oils were produced from pyrolysis of bunches of empty palm fruit at different temperatures. Physicochemical chemical characteristics of the bio-oils were evaluated using standard analytical procedures. Allelopathic activities of the bio-oils were evaluated against three selected seeds (tomatoes, okra and Amaranthus). The percentage germination inhibition was calculated for each seed after 72 h of germination. The yields of the bio-oils are 22.07%, 35.13% and 37.47% at 400 °C, 500 °C, and 600 °C, respectively. The bio-oils are acidic and contain compounds such as phenols, phenol derivatives, alkanes, and organic acids. The results revealed that the empty palm fruit bunches’ bio-oils have inhibitory effects on the three selected seeds. The percentage seed germination decreased with increasing concentration of the bio-oils while the inhibitory effect of the bio-oils on seedling growth increased significantly with increasing concentration of the empty palm fruit bunches’ bio-oils. The bio-oils obtained at different pyrolytic temperatures showed appreciable allelopathic activities.