Total Phenolic Content of Oil Palm Roots (Elaeis Guineensis Jacq.) As Preliminary Health Indicators in Oil Palm Plantation

Abstract

Phenol and its derivatives are known as major phytochemical compound incorporated in plant defense or resistance. Oil palm (Elaeis guineensis Jacq.) is an important oil-producing species which prone to infection caused by Ganoderma boninense Pat., causing basal stem rot to the plant. Oil palm may accumulate or secrete related phenolic compounds into rhizospheric region as early mechanism in plant defense against G. boninense. This study investigated the role of total phenolic content in oil palm roots as an indicator to health status of plant in plantation. Oil palm roots were sampled from four representative plantations namely Kuala Bekala (KB), Medan Johor (MJ) from Medan city and Bilah Barat (BB), Kualuh Hulu (KH) from Labuhan Batu district. Phenol concentration was measured using Folin-Ciocalteau colorimetry method, expressed as μg GAE/mL from four different root macerates, using 100% MeOH, 100% MeOH with sonication, 80% MeOH and sterile distilled water (H2O). The results showed that phenolic compounds were higher in healthy than diseased plant. Solvent 80% MeOH was considered as the best solvent in extracting phenolic compounds both from diseased and healthy plants (P < 0.001) both quantitative and qualitatively. The differences of phenol content in oil palm roots may then reflect the fitness status of plant in the presence or absence of G. boninense.