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Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential
Thesis (MSc)--Stellenbosch University, 2023.
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| Format: | Thesis |
| Language: | English |
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Stellenbosch : Stellenbosch University
2023
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| _version_ | 1867613883865235456 |
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| access_status_str | Open Access |
| author | Prinsloo, Jared Reece |
| author2 | Jacobs, Karin |
| author_browse | Jacobs, Karin Prinsloo, Jared Reece |
| author_facet | Jacobs, Karin Prinsloo, Jared Reece |
| author_sort | Prinsloo, Jared Reece |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MSc)--Stellenbosch University, 2023. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/128386 |
| institution | Stellenbosch University (South Africa) |
| language | English |
| last_indexed | 2026-06-10T12:43:13.574Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2023 |
| publishDateRange | 2023 |
| publishDateSort | 2023 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/128386 Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential Prinsloo, Jared Reece Jacobs, Karin Brink, Casper Stellenbosch University. Faculty of Science. Dept. of Microbiology. Biofilms Soil microbiology -- South Africa -- Cape Floristic Region Fynbos ecology Biofertilizers Fungus-bacterium relationships UCTD Thesis (MSc)--Stellenbosch University, 2023. ENGLISH ABSTRACT: Increasing evidence has shown that conventional agriculture will not be able to supply enough food for the growing population. This increased demand has led to an increased dependency on synthetic, chemical fertilizers, as the soil itself cannot meet the nutritional requirements necessary for adequate crop production. Extensive chemical fertilizer usage has been shown to cause: loss of soil biodiversity, air pollution, and eutrophication. Biofertilizers are popular alternatives to chemical fertilizers as they are capable of restoring soil fertility and improving crop yield without the negative environmental impacts of chemical fertilisers. Biofertilizers are composed of single or mixed species microbial cultures which are beneficial for soil fertility and/or promote plant growth. Fungal-bacterial biofilms have become strong biofertilizer candidates, as they combine the resilience of a biofilm with the nutrient cycling abilities of both fungi and bacteria. This study’s first aim was to investigate the species specific interaction between Penicillium polonicum and Paenibacillus polymyxa, isolated from the oligotrophic soils of the Cape Floristic Region in South Africa. The study also aims to assess whether the biofilm of P. polonicum and Pa. polymyxa can function as a biofertilizer. Using confocal laser scanning microscopy and scanning electron microscopy, it was possible to study the morphology of the biofilm. The association between P. polonicum and Pa. polymyxa was found to be highly species specific, as neither organism would form a biofilm with a different fungal or bacterial species. The bacterial cells attach to the fungal hyphae in dense clusters toward the centre of fungal flocs. These clusters were found bound in an exopolysaccharide matrix, which may create a microaerophilic environment for Pa. polymyxa to fix nitrogen. cDNA amplified fragment length polymorphism analysis (cDNA-AFLP) was used to qualitatively observe changes in gene expression when P. polonicum and Pa. polymyxa were grown in co-culture versus when they were grown separately or with other microorganisms. Several changes in gene expression were observed, however, further research would be needed to determine the identity and function of these genes. This study performed both field and potting trials to examine the effects of the biofilm both under controlled conditions and in the field. Harvest analysis and soil chemical assays were performed to assess the ability of the biofilm to both improve crop yield and soil fertility, respectively. This study also used automated intergenic spacer region analysis to determine how the application of the biofilm would affect the diversity of fungal and bacterial communities in the soil. For both the field and potting trials, it was found that the application of the P. polonicum + Pa. polymyxa biofertilizer in the dosages used for this study, had no significant effect on both soil fertility and soil microbial diversity. This study found that current practices regarding the use of biofertilizers in agriculture require considerable research and optimisation before they can be considered as viable alternatives to chemical fertilizers. Furthermore, research into the genes involved in selective nature of the P. polonicum + Pa. polymyxa biofilm could provide greater insight into biofilm formation and may provide new tools, which could be used to further manipulate biofilms for biotechnological applications. AFRIKAANSE OPSOMMING: Toenemende bewyse het getoon dat konvensionele landbou nie genoeg voedsel vir die groeiende bevolking sal kan voorsien nie. Hierdie verhoogde vraag het gelei tot 'n groter afhanklikheid van sintetiese, chemiese bemestingstowwe, aangesien die grond self nie genoeg voedingsvereistes vir voldoende gewasproduksie het nie. Uitgebreide gebruik van chemiese kunsmis veroorsaak: verlies aan grondbiodiversiteit, lugbesoedeling en eutrofikasie. Biobemesting is n’ gewilde alternatiewe vir chemiese bemestingstowwe aangesien dat dit grondvrugbaarheid kan herstel en oesopbrengs te verbeter sonder die negatiewe omgewingsimpakte van chemiese bemestingstowwe. Biobemestingstowwe is saamgestel uit enkel- of gemengde spesies mikrobiese culture, wat voordelig is vir grondvrugbaarheid en/of plantgroei bevorder. Swam-bakteriële biofilms is sterk kandidate vir biobemesting aangesien hulle die veerkragtigheid van 'n biofilm kombineer met die voedingstof-siklusvermoë van beide swamme en bakterieë. Hierdie studie se eerste doel is om die spesie-spesifieke interaksie tussen Penicillium polonicum en Paenibacillus polymyxa te ondersoek. Altwee mikroorganismes is geïsoleer uit die oligotrofiese gronde van die Kaapse Floristiese Streek in Suid-Afrika. Die studie het ook ten doel om te bepaal of die biofilm van P. polonicum en Pa. polymyxa as 'n biobemesting kan optree. Met behulp van konfokale laserskanderingsmikroskopie en skandeerelektronmikroskopie, was dit moontlik om die morfologie van die biofilm te bestudeer. Dit was ontdek dat die assosiasie tussen P. polonicum en Pa. polymyxa hoogs spesiespesifiek is, aangesien nie een van die organismes met 'n ander swam- of bakteriese spesie ‘n biofilm sal vorm nie. Die bakteriese selle heg aan die swamhifes in digte trosse na die middel van swamvlokkies. Hierdie trosse is gevind in 'n eksopolisakkariedmatriks gebind, wat 'n mikroaërofiele omgewing vir Pa. polymyxa kan skep om stikstof te bind. cDNA geamplifiseerde fragmentlengte polimorfisme-analise (cDNA-AFLP) is gebruik om veranderinge in geenuitdrukking kwalitatief waar te neem wanneer P. polonicum en Pa. polymyxa in ko-kultuur gekweek is teenoor wanneer hulle afsonderlik of met ander mikroörganismes gekweek is. Verskeie veranderinge in geenuitdrukking is waargeneem, maar verdere navorsing sal nodig wees om die identiteit en funksie van hierdie gene te bepaal. Hierdie studie het beide veld- en potproewe uitgevoer om die effekte van die biofilm beide onder gekontroleerde toestande en in die veld te ondersoek. Oesanalise en grondchemiese toetse is uitgevoer om die vermoë van die biofilm om beide oesopbrengs en grondvrugbaarheid onderskeidelik te verbeter, te bepaal. Hierdie studie het ook geoutomatiseerde intergeniese spasieerstreek-analise gebruik om te bepaal hoe die toepassing van die biofilm die diversiteit van swam- en bakteriese gemeenskappe in die grond sal beïnvloed. Vir beide die veld- en potproewe is gevind dat die toediening van die P. polonicum + Pa. polymyxa biofilm, in die dosisse wat vir hierdie studie gebruik is, geen betekenisvolle effek op beide grondvrugbaarheid en grondmikrobiese diversiteit gehad het nie. Hierdie studie het bevind dat huidige praktyke met betrekking tot die gebruik van biobemesting in die landbou aansienlike navorsing en optimalisering verg voordat dit as lewensvatbare alternatiewe vir chemiese bemesting beskou kan word. Verder kan navorsing oor die gene betrokke by selektiewe aard van die P. polonicum + Pa. polymyxa biofilm groter insig in biofilmvorming verskaf en kan nuwe gereedskap verskaf wat gebruik kan word om biofilms verder te manipuleer vir biotegnologiese toepassings. Masters 2023-02-23T10:54:43Z 2023-08-30T13:10:57Z 2023-02-23 2023-02-23T10:54:43Z 2023-08-31T09:18:33Z 2023-02-23T10:54:43Z 2023-08-31T09:18:33Z 2023-03 Thesis https://scholar.sun.ac.za/handle/10019.1/128386 en Stellenbosch University application/pdf 177 pages : illustrations, maps application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Biofilms Soil microbiology -- South Africa -- Cape Floristic Region Fynbos ecology Biofertilizers Fungus-bacterium relationships UCTD Prinsloo, Jared Reece Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential |
| title | Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential |
| title_full | Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential |
| title_fullStr | Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential |
| title_full_unstemmed | Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential |
| title_short | Investigating a species specific fungal-bacterial biofilm isolated from oligotrophic Fynbos soils and assessing its biofertilizer potential |
| title_sort | investigating a species specific fungal bacterial biofilm isolated from oligotrophic fynbos soils and assessing its biofertilizer potential |
| topic | Biofilms Soil microbiology -- South Africa -- Cape Floristic Region Fynbos ecology Biofertilizers Fungus-bacterium relationships UCTD |
| url | https://scholar.sun.ac.za/handle/10019.1/128386 |
| work_keys_str_mv | AT prinsloojaredreece investigatingaspeciesspecificfungalbacterialbiofilmisolatedfromoligotrophicfynbossoilsandassessingitsbiofertilizerpotential |