Antagonistic Activity of Siderophore-Producing Bacteria from Black Rice Rhizosphere against Rice Blast Fungus <i>Pyricularia oryzae</i>

Rice blast caused by Pyricularia oryzae, which is a major threat to food security worldwide, markedly decreases the yield of rice. Some rhizobacteria called 'plant growth-promoting rhizobacteria' inhibit plant pathogens and improve growth secreting iron-chelating siderophores. The decreased availability iron adversely affects survival pathogens, especially fungal in rhizosphere. This study aimed determine morphological diversity siderophore-producing bacteria, analyze type siderophores produced examine their growth-inhibitory activity against oryzae. were isolated from rhizosphere Sembada Hitam variety black rice plants Pakem, Sleman, Yogyakarta, Indonesia. In total, 12 distinct isolates screened for production It was found that 9 out bacteria siderophore most them Gram positive bacteria. best with different used further studies. IS3 IS14 be producer hydroxamate mixed hydroxamate-carboxylate siderophore, respectively. dual culture assay, showed strong antagonistic effect oryzae 81.17% inhibition.