Akademik Veri Yönetim Sistemi
9th International Entomopathogens and Microbial Control Congress, Trabzon, Türkiye, 28 - 31 Ekim 2024, ss.123
In this study, it was aimed to test the antimicrobial activity of secondary metabolites obtained from local fungal isolates KTU-51 (Beauvaria bassina) and 4-Güm-A (Metarhizium anisopliae) against plant pathogenic bacteria (Pseudomonas syringae pv. tomato, Erwinia amylovora) and fungi (Fusarium oxysporum and Alternaria alternata). For fungal secondary metabolite production, firstly, KTU-51 and 4-Güm-A were incubated at 28 °C for 1 week on potato dextrose agar (PDA) plates and sporulation was achieved. Then spores were collected by scraping and, dissolved in 5 ml of 1% Tween 80 solution to create a stock spore solution. 50 ml sabouraud dextrose broth (SDB) medium was inoculated at 1x 107 conidia/ml. Secondly, to understanding effect of light and dark the differenties on secondary metabolite production and its antimicrobial potency one flasks was tightly wrapped with aluminum foil to prevent light penetration, and called the dark phase. The unwrapped flask was named light phase and both flasks were incubated at SDB, in a 30℃,160 rpm for 14 days. At the end of the incubation period, the extract was obtained by filtration. Equal volumes of fungi culture extract and ethyl acetate (1:1 v/v) were mixed in 250 mL flasks for 1 hour at room temperature. Then the mixture was transferred to a large flask and allowed to stand for 30 min for phase separation. The ethyl acetate phase (upper phase) was separated with sterile pipette and concentrated at 42 ºC using an rotary evaporator. Lastly, concentrated ethyl acetat extracts were used at disk diffussion assay for determination of antimicrobial sensivity on plant pathogenic bacteria (Pseudomonas syringae pv. tomato and Erwinia amylovora) and fungi (Fusarium oxysporum and Alternaria alternata). As a result, a small zone formation was observed in plant pathogenic fungi and pathogenic bacteria.
Keywords: Entomopathogenic fungi, Secondary metabolite, Biological control, Pseudomonas syringae, pv. tomato, Erwinia amylovora, Fusarium oxysporum, Alternaria alternata