The synthesis of silver, zinc and calcium nanoparticles from antarctic bacterium and effects of these nanoparticles against plant pathogens
Tez Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Yıldız Teknik Üniversitesi, Fen Bilimleri Enstitüsü, Türkiye
Tez Danışmanı: Prof. Dr. Sevgi Maraklı
Tezin Onay Tarihi: 2025
Tezin Dili: İngilizce
Desteklendiği Program: Diğer
Özet:
Psychrophiles are cold resistant microorganisms, belonging to the extremophile group. These creatures have frequently used in every field. In recent years, nanoparticles (NPs) have been extensively researched in different industries. The aim of this thesis was to examine the effect of green synthesized NPs on important Fusarium species that cause significant losses in agriculture. For this purpose, silver (Ag), zinc oxide (ZnO) and calcium oxide (CaO) NPs were produced from Psychrobacter sp. TaeBurcu001 bacterium by green synthesis method and the antifungal effects of these NPs on Fusarium verticillioides, F. oxysporum, F. equiseti, and F. acuminatum pathogens were investigated by morphological and molecular analyses. The produced NPs were characterized by techniques appropriate to the literature. The antifungal effects of NPs against Fusarium species were tested at different concentrations and chemical fungicide (Talendo®) was added as a positive control. The most effective inhibition was observed in 1mg/ml concentrations, except CaO NP. The expressions of Mgv1 and Pod genes were also examined in each group. Mgv1 gene did not increase in any of the four species. On the other hand, the expression of Mgv1 gene decreased in Ag NP (12.5 fold, p<0.0001) and ZnO NP (100 fold, p<0.0001) groups in F. oxysporum. Similarly, in F. equiseti species, the expression was reduced in Ag NP by 6.25 fold (p<0.0001) and ZnO NP by 100 fold (p<0.0001). However, Pod gene expression was increased in Ag NP (17.8 fold, p<0.0332) treated groups in F. verticillioides. However, Ag NP decreased by 1.6 fold change (p<0.0021) and ZnO NP decreased by 10 fold (p<0.0002) in F. oxysporum. In F. equiseti species, both Ag NP (6.25 fold) and ZnO NP (100 fold) decreased (p<0.0001). No significant change was observed in F. acuminatum. The findings will provide a new perspective on how these NPs can be used as alternatives to commonly used pesticides in agriculture. However, detailed in vitro and also in planta analyses should be performed.