Biocontrol of Fusarium spp. in vitro and in vine cuttings using Bacillus sp. F62

Abstract

Fusarium spp., the causal agent of Fusarium wilt, cause substantial economic losses in viticulture, mainly in tropical regions. This study aimed to assess the biocontrol potential of Bacillus sp. F62 against Fusarium spp., both in vitro and in rootstock cuttings of the SO4 variety. To this end, the in vitro antagonism was evaluated through diffusible and volatile compounds synthesized by Bacillus sp. F62 on three Fusarium spp. isolates. Subsequently, the isolate FusA06-18 was selected for a rootstock cutting experiment. The vine cuttings underwent the following treatments: control, pathogen inoculation (Fus), bacterial inoculation (Bac), and bacterial followed by pathogen inoculation (Bac + Fus). Our findings revealed an average reduction of 39.1% in the mycelial growth of the pathogen through dual culture assay and a decrease of 11.6% in the Fusarium spp. radial growth due to the effects of volatile compounds. In the experiment with vine cuttings, applying Bacillus sp. F62 reduced the pathogen re-isolation frequency from 81.7% (Fus) to 63.3% (Bac + Fus). Therefore, Bacillus sp. F62 effectively suppressed the mycelial growth of Fusarium spp. and reduced the Fusarium wilt incidence in vine cuttings of the rootstock ‘SO4’.

Keywords

• Antagonism
• bioagent
• Fusarium wilt
• vine rootstock