Fusarium species are among the most important fungal pathogens of cereals able to synthetize harmful mycotoxins. The most important cereal diseases are caused by co-occurrence of multiple Fusarium species, mainly F. graminearum, producer of deoxynivalenol, and F. proliferatum, producer of fumonisins. Nowadays, the increasing interest in reducing chemicals in agriculture prompts researchers to select new eco-friendly strategies against fungal diseases. This study aimed to select potential bacterial bio-control agents to control Fusarium species. Thirty-three Bacillus strains belonging to Bacillus velezensis, B. amiloliquefaciens, B. subtilis, B. licheniformis, B. mojavensis, B. simplex, B. megaterium, B. oleronius, B. pumilus and B. safensis, isolated from wheat grains and flours, were considered. The antagonistic activity against F. graminearum and F. proliferatum species, by co-colture assay, and the antimicrobial effect of bacteria filtrates were evaluated. Twenty-three strains, including all B. velezensis and B. amyloliquefaciens strains, showed a good antagonistic activity, with mycelial growth inhibition values up to 70%. Moreover, 14 strains produced active compounds inhibiting mycelial growth up to 60%. To elucidate the molecular mechanisms associated with the activity against Fusarium species, all Bacillus strains were screened for the presence of genes involved in the synthesis of active biomolecules, including surfactin, fengycin, iturin, bacillomycin, bacilysin, difficidin and mycosubtilin. Furthermore, to have comprehensive information on the potential antimicrobial metabolites produced by strains showing marked antifungal activity, we performed a genome analysis of secondary metabolite biosynthetic gene clusters. In addition, the effect of Bacillus strains on deoxynivalenol and fumonisin production when co-cultured with Fusarium strains, was also studied. Although any effect was observed in fumonisin production, half of Bacillus strains inhibited completely deoxynivalenol production.
Selection of Bacillus strains as potential biocontrol agents against mycotoxigenic Fusarium species occurring on cereals.
Masiello M.;Touati R.;Somma S.;Haidukowski M.;Pentimone I.;Moretti A.;De Bellis P.
2025
Abstract
Fusarium species are among the most important fungal pathogens of cereals able to synthetize harmful mycotoxins. The most important cereal diseases are caused by co-occurrence of multiple Fusarium species, mainly F. graminearum, producer of deoxynivalenol, and F. proliferatum, producer of fumonisins. Nowadays, the increasing interest in reducing chemicals in agriculture prompts researchers to select new eco-friendly strategies against fungal diseases. This study aimed to select potential bacterial bio-control agents to control Fusarium species. Thirty-three Bacillus strains belonging to Bacillus velezensis, B. amiloliquefaciens, B. subtilis, B. licheniformis, B. mojavensis, B. simplex, B. megaterium, B. oleronius, B. pumilus and B. safensis, isolated from wheat grains and flours, were considered. The antagonistic activity against F. graminearum and F. proliferatum species, by co-colture assay, and the antimicrobial effect of bacteria filtrates were evaluated. Twenty-three strains, including all B. velezensis and B. amyloliquefaciens strains, showed a good antagonistic activity, with mycelial growth inhibition values up to 70%. Moreover, 14 strains produced active compounds inhibiting mycelial growth up to 60%. To elucidate the molecular mechanisms associated with the activity against Fusarium species, all Bacillus strains were screened for the presence of genes involved in the synthesis of active biomolecules, including surfactin, fengycin, iturin, bacillomycin, bacilysin, difficidin and mycosubtilin. Furthermore, to have comprehensive information on the potential antimicrobial metabolites produced by strains showing marked antifungal activity, we performed a genome analysis of secondary metabolite biosynthetic gene clusters. In addition, the effect of Bacillus strains on deoxynivalenol and fumonisin production when co-cultured with Fusarium strains, was also studied. Although any effect was observed in fumonisin production, half of Bacillus strains inhibited completely deoxynivalenol production.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
