Isolation and Identification of Antifungal Compounds from Bacillus subtilis Inhibiting the Growth of Fusarium incarnatum (Desm.) Sacc. incitant of Crossandra Wilt

摘要

Antagonistic microorganisms Bacillus spp against Fusarium incarnatum were isolated and their antifungal activities were investigated. Thirty Bacillus subtilis isolates were isolated from various soil samples and all the isolates were found to antagonize the pathogen with varying degree ranging from 37.59% to 74.96%. Crude culture filtrates from nine effective Bacillus spp were extracted and tested for their efficacy against test pathogen F.incarnatum Among them, isolate Bs-10 found to be most effective isolate with mycelia inhibition of 47.6 per cent and based on dual culture and antibiotic assay Bs-10 selected as an antagonistic microorganism with potential for use in further studies. Crude antibiotics were analyzed for noval metabolites through GC-MS analysis revealed the presence of antifungal volatile compounds from isolate Bs-10. The promising volatile compounds observed through GC-MS, included dedeconal, trideconol, tetradecanoic acid, pentadecinoic acid, octodeconoic acid, 9-octodeconoic acid, hexadeconoic acid, 1-2-benzenedicarboxylic acid, n-pyrrolidine, ipconazole, heptadeconoic acid, Docosane, nonacosane, and cyclohexane. These compounds may play an important role in the inhibition of mycelial growth and reducing disease level. Studiesare underway to understand this phenomenon under glass house and field conditions.