Effect of different carbon and nitrogen sources combination in medium for production of biocontrol agent Trichoderma harzianum

Abstract

The increasing usage of chemicals for plant protection in recent years has become a serious problem. One of the possible solutions is use of beneficial microorganisms instead of synthetic fungicides, which will contribute to the protection of the environment and human health. Since the fungi Aspergillus flavus and Fusarium graminearum are the most important pathogens that cause maize diseases and produce mycotoxins, the potential of Trichoderma harzianum for biocontrol of both phytopathogens was examined in this paper. The aim of this paper was to study the influence of different carbon and nitrogen combinations in the medium for T. harzianum production. T. harzianum was cultivated in Erlenmeyer flasks and the effect of cultivation broth against selected maize pathogens was tested using well diffusion method. The results of this study showed that the combination of different carbon and nitrogen sources in the T. harzianum cultivation medium statistically significantly affects the production of Trichoderma cultivation broth effective on two tested phytopathogens. Dextrose as a carbon source and soybean flour as a nitrogen source proved to be the best combination in the medium for production of T. harzianum cultivation broth effective on A. flavus and F. graminearum. Maximal inhibition zone diameters of 31 mm and 56.33 mm were registered in those medium formulations for A. flavus and F. graminearum, respectively. These researches represent an important step for further research in which a medium of low market value would be selected. This would reduce the price of the production process but also the final product.

Sve veća upotreba hemijskih sredstava za zaštitu bilja poslednjih godina postala je ozbiljan problem. Upotreba korisnih mikroorganizama umesto sintetičkih fungicida u biološkoj zaštiti sigurno je jedno od rešenja koje doprinose zaštiti životne sredine i ljudskog zdravlja. S obzirom na to da se gljive Aspergillus flavus i Fusarium graminearum pominju kao najvažniji prouzrokovači bolesti kukuruza, proizvođači mikotoksina, u ovom radu ispitan je antifungalni efekat Trichoderma harzianum na obe fitopatogene gljive. Cilj ovog rada je ispitati uticaj različitih kombinacija ugljenika i azota u podlozi za proizvodnju T. harzianum. Kultivacija T. harzianum izvedena je u erlenmajerima na rotacionoj tresilici, a aktivnost dobijene kultivacione tečnosti na odabrane fitopatogene kukuruza ispitana je difuzionom metodom sa bunarima. Rezultati ovog rada pokazali su da kombinacija različitih izvora ugljenika i azota u podlozi statistički značajno utiče na proizvodnju Trichoderma kultivacione tečnosti efikasne na dve testirane fitopatogene gljive. Kombinacija koja sadrži dekstrozu kao izvor ugljenika i sojino brašno kao izvor azota pokazala se najboljom za formulaciju podloge za proizvodnju T. harzianum kultivacione tečnosti efikasne na patogene kukuruza, A. flavus i F. graminearum, formirajući maksimalne prečnike zona inhibicije od 31 mm, odnosno 56,33 mm.