Study on the Biocontrol Potential of Antifungal Peptides Produced by against That Infects the Passion Fruit .

A bacterium identified as with a growth inhibitory effect against , a pathogen that caused basal stem rot in the passion fruit , was isolated in this study. From the fermentation broth of , a type of antifungal peptide (named BVAP) with a molecular weight of ca. 1.5 kDa was purified and found to be fengycin. BVAP suppressed mycelial growth in with an IC of 5.58 μg/mL, which was superior to those of the chemical fungicides thiram (41.24 μg/mL) and hymexazol (343.31 μg/mL). The antifungal activity remained stable after exposure to 50-100 °C or following incubation with solutions at pH 1-3. Further research revealed that BVAP increased the permeability of the mycelial membrane, brought about swelling at the tips of hyphae, and elicited abnormal accumulation of nucleic acids and chitin at the sites of swelling. These findings indicate that BVAP possessed a remarkable biocontrol potential toward .