In vitro antifungal potential of surfactin isolated from rhizospheric Bacillus thuringiensis Berliner 1915 against maize (Zea mays L.) fungal phytopathogen Fusarium graminearum Schwabe

Abstract

Fusarium graminearum fungus cause significant loss in maize (Zea mays L.) and other cereal crops all over the world. The usage of chemical agents cause severe environmental problems. Bacillus species and other plant growth-promoting bacteria (PGPR) play key role in biopesticide development. A wide range of environmentally safe antimicrobial agents are already being manufactured. The current investigation was focused on exploring the antifungal activity of Bacillus thuringiensis lipopeptide surfactin against fungal phytopathogen Fusarium graminearum. B. thuringensis was isolated from the rhizosphere of maize crop and cultivated to produce lipopeptides. Surfactin was identified by high-performance liquid chromatography (HPLC) from the extract at 210 nm, retention time 3-5 minutes and the obtained peaks area was 3.990. The growth of F. graminearum was successfully inhibited by surfactin at different concentrations. Among these, 80 % concentration showed the highest zone of inhibition in comparison to 60 %, 40 % and 20 % concentrations (p < 0.005), respectively. The current study concludes B. thuringensis lipopeptide surfactin has a high potential to inhibit the growth of F. graminearum.