Bakterijski izolati iz roda Pseudomonas kao inhibitori rasta micelija slatkovodnih patogenih mikroorganizama iz skupine Oomycota

undergraduate thesis

• Title (english): Bacterial isolates from the genus Pseudomonas as inhibitors of mycelial growth of freshwater oomycete pathogens
• Author: Matilda Majerčak-Škorlić
• Mentor: Ana Bielen (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biology and Microbial Genetics); Zagreb
• Defense date and country: 2023-06-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Patogeni mikroorganizmi Aphanomyces astaci i Saprolegnia parasitica uzrokuju gubitke u slatkovodnoj akvakulturi rakova i riba te je potrebno razviti ekološki prihvatljive metode njihove kontrole. Cilj ovog rada bio je istražiti inhibicijski potencijal 25 izolata roda Pseudomonas prema rastu micelija ovih patogena. Najprije je filogenetskom analizom gena koji kodira za 16S rRNA izvršena identifikacija izolata, i to 7/25 izolata (28 %) do vrste, 4/25 izolata (16 %) do podgrupe te 11/25 (44 %) do grupe unutar roda Pseudomonas. Nadalje, in vitro testovima inhibicije je utvrđeno da je čak 44 % izolata snažno inhibiralo rast micelija A. astaci te su se najjačima istaknuli izolati grupe fluorescens. Inhibicija patogena S. parasitica bila je znatno slabija, ali ipak primjetna kod nekih izolata iz grupa fluorescens i lutea. Zaključno, rezultati ovog rada ukazuju na moguću primjenu bakterija iz roda Pseudomonas u svrhu biokontrole patogena A. astaci i S. parasitica u akvakulturi.

Abstract (english)

The pathogenic microorganisms Aphanomyces astaci and Saprolegnia parasitica cause losses in freshwater aquaculture and it is necessary to develop environmentally acceptable methods of their control. The aim of this study was to investigate the inhibitory potential of 25 isolates of the genus Pseudomonas against their mycelial growth. First, the phylogenetic analysis of the gene that encodes 16S rRNA was applied to identify the isolates, namely 7/25 isolates (28%) were classified to the species level, 4/25 isolates (16%) to the subgroup, and 11/25 (44%) to the group within the genus Pseudomonas. Furthermore, in vitro inhibition tests showed that 44% of the isolates strongly inhibited the growth of A. astaci mycelia, mostly the isolates from the fluorescens group. Inhibition of the pathogen S. parasitica was significantly weaker but still noticeable for some isolates from the fluorescens and lutea groups. In conclusion, the results of this work indicate the possible use of bacteria of the genus Pseudomonas for A. astaci and S. parasitica biocontrol in aquaculture.

• Keywords: akvakultura; biokontrola; 16S rRNA; testovi inhibicije; filogenetsko stablo
• Keywords (english): aquaculture; biocontrol; 16S rRNA; inhibition tests; phylogenetic tree
• Language: croatian
• URN:NBN: urn:nbn:hr:159:413069
• Study programme: Title: Biotechnology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-04-19 11:31:44