ABSTRACT

Sugarcane (Saccharum officinarum L.) is a crucial crop contributing significantly to the economy and industries of the Philippines. However, its productivity is threatened by ringspot disease, caused by Epicoccum sorghinum, which negatively affects growth and yield. This study aims to evaluate the antagonistic potential of endophytic bacteria isolated from sugarcane against E. sorghinum using a Dual Culture Assay (DCA) and Volatile Compound Assay (VCA). The study also characterizes the bacterial species through morpho-cultural and Gram staining analysis and identifies them using Polymerase Chain Reaction and Phylogenetic Analysis (PCR-PA). The bacterial isolates, obtained from sugarcane stalks and maintained in the laboratory, were assessed for their inhibitory effects on the pathogen. The findings revealed that Burkholderia gladioli (Camingawan) exhibited the highest inhibition in the DCA (57.79%), followed by Stenotrophomonas rhizophila (Oringao) (16.55%). In the VCA, Bacillus pumilus (Binicuil) was the most effective, showing a 49.56% inhibition rate. Molecular characterization using 16S rRNA sequencing confirmed the identity of these endophytic bacteria. The results indicate that these bacterial strains possess strong antagonistic properties against E. sorghinum, demonstrating their potential as sustainable biocontrol agents. This study provides valuable insights into endophytic bacteria as an eco-friendly alternative to chemical pesticides for managing ringspot disease in sugarcane. Further research should explore field applications and formulation development to enhance the practical deployment of these biocontrol agents in sugarcane farms.