In vitro antifungal potential of surfactin isolated from rhizospheric Bacillus thuringiensis Berliner 1915 against maize (Zea mays L.) fungal phytopathogen Fusarium graminearum Schwabe | In vitro protiglivni potencial surfaktina, izoliranega iz bakterije Bacillus thuringiensis Berliner 1915 iz rizosfere koruze (Zea mays L.) proti patogeni glivi Fusarium graminearum Schwabe

anglais. 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.

slovène. Gliva Fusarium graminearum povzroča znantne izgube v pridelku koruze in drugih žit širom po svetu. Uporaba kemičnih sredstev za zatiranje povzroča resne okoljske probleme. Vrste iz rodu Bacillus in druge rast vzpodbujajoče bakterije (PGPR) igrajo ključno vlogo pri razvoju biopesticidov. Proizveden je bil že širok spekter okolju prijaznih antimikrobnih agensov. Raziskava se osredotoča na uporabo protiglivne aktivnosti lipopeptidnih surfaktinov iz bakterije Bacillus thuringiensis proti patogeni glivi Fusarium graminearum. Bakterija B. thuringensis je bila izolirana iz rizosfere posevka koruze in gojena za proizvodno lipopeptidov. Surfaktin je bil določen s tekočinsko kromatografijo visoke ločljivosti (HPLC) iz izvlečka pri 210 nm, retencijskim časom 3-5 minut, dobljeni višek je bil 3.990. Rast patogene glive je bila uspešno zavrta pri različnih koncentracijah surfaktina. 80 % koncentracija surfaktina je pokazala največjo sposobnost zaviranja v primerjavi s koncentracijami 60 %, 40 % in 20 % (p < 0,005). Na osnovi te raziskave lahko zaključimo, da ima lipopeptidni surfaktin iz bakterije B. thuringensis velik potencial za zaviranje rasti glive F. graminearum.