Research Publication Details

Abstract

Basal stem rot (BSR) is a serious oil palm disease caused by Ganoderma fungi resulting in severe yield losses in Southeast Asia. Conventional management strategies including chemical treatments, sanitation and cultural practices remain largely ineffective, necessitating the exploration of sustainable biological alternatives. This study aimed to evaluate the antagonistic potential oof selected entomopathogenic fungi (EPF) against G. boninense isolates from oil palm plantations in Sabah, Malaysia. Six G. boninense isolates were obtained from infected oil palm trees, while five EPF — Cordyceps jakajanicola, Cordyceps tenuipes, Blackwellomyces calendulinus, Purpureocillium lilacinum, and Simplicillium formicae — were newly isolated from Danum Valley Conservation Area, INFAPRO, Kinabalu Park, and Tawau Hills Park and identified using morphomolecular approaches. Antagonistic activity was evaluated using a dual culture assay, with nystatin (200 and 300 µL/mL) included as a positive control. Among EPF, C. jakajanicola and P. lilacinum exhibited strong antagonistic activity against G. boninense, with inhibition ranging from 38.6 – 70.37%, and 32.76 – 70.18%, respectively. Moderate inhibition was observed for C. tenuipes (23.81 – 64.41%) and B. calandulinus (13.64 – 45.54%), while S. formicae showed the lowest inhibitory effect (13.73 – 39.34%.). For comparison, the positive control nystatin showed the highest inhibition, ranging from 76.02–79.76% at 300 µL/mL and 67.86–75.57% at 200 µL/mL. All observed inhibitory effects were statistically significant (p ≤ 0.05). These findings illustrate that selected EPF, particularly, C. jakajanicola, and P. lilacinum, possess promising antagonistic potential against G. boninense and may serve as eco-friendly biocontrol agents for the management of basal stem rot in oil palm. Key words: antagonistic activity, dual culture, growth inhibition, pathogen and sustainable agriculture.