Abstract

The purpose of this study was to identify endophytic fungi associated with Uncaria gambier (Hunter) Roxb. in Lima Puluh Kota, West Sumatra, Indonesia and to assess their antifungal properties. Fourteen endophytic fungi were identified from the leaf tissues of gambir. All the isolates were tested for their pathogenicity, and nine were found to be non-pathogenic. Using a dual culture assay in Petri dishes, the antagonistic activity of the nine non-pathogen isolates was assessed against F. oxysporum. After two isolates with the highest inhibitory activity were selected, the metabolite extracts of endophytic fungi were tested against F. oxysporum using antifungal assay extraction. Two endophytic fungal isolates namely DL22 and DP12 showed good activity as antifungal agents. Extracts of the metabolites of isolates DL22 (25%) and DP12 (25%) decreased the pathogenic fungal infection level by 32–34%. Among the tested endophytic fungi, isolate DL22 exhibited the strongest antagonistic activity, inhibiting F. oxysporum by 34% at a 25% concentration. This suggests its promising potential for further development as a natural biocontrol agent against F. oxysporum.