ANTIMICROBIAL ACTIVITY OF CIDTOSAN-INDUCED PHENOLIC ACIDS IN OIL-PALM ROOTS AGAINST GANODERMA BONINENSE

Abstract

This paper discusses the accumulation of phenolic acids in three different varieties of oil palm and in vitro antimicrobial activity against Ganoderma boninense after elicitation with chitosan. The phenolic acids detected in oil-palm root tissues were syringic acid (SA), caffeic acid (CA) and 4-hydroxybenzoic acid (4-HBA). The in planta accumulation were monitored for four weeks and the in vitro antimicrobial activities ofthe phenolics against the pathogen for eleven days. The radial growth of the pathogens on 10% PDA and on oil-palm root agar (OPRA), ameliorated with the three phenolics, with range concentration of50-110 ~g mL-1 were recorded daily. AVROS variety was reported to have the highest amount of the three phenolic acids compared to Ekona and Calabar varieties. SA was found to be the most active in inhibiting the pathogen, followed by CA and 4-HBA. The latter was virtually inactive, both in 10% PDA and OPRA. Antifungal activity of SA and CA was detected, which was consistent with those detected in oil-palm roots.