Repozitorij Univerze v Novi Gorici

Izpis gradiva
A+ | A- | Pomoč | SLO | ENG

Naslov:Exploration of yeast biodiversity potential for development of alternative biofungicides in viticulture : dissertation
Avtorji:ID Adesida, Rowland (Avtor)
ID Sternad Lemut, Melita (Mentor) Več o mentorju... Novo okno
ID Butinar, Lorena (Mentor) Več o mentorju... Novo okno
Datoteke:URL http://repozitorij.ung.si/IzpisGradiva.php?id=7369
 
.pdf Rowland_Adetayo_Adesida.pdf (4,17 MB)
MD5: F1682A05E6B8AC0C243F2DBF088BA989
 
Jezik:Angleški jezik
Vrsta gradiva:Doktorsko delo/naloga
Tipologija:2.08 - Doktorska disertacija
Organizacija:FPŠ - Fakulteta za podiplomski študij
Opis:Botrytis cinerea Pers., the fungal plant pathogen and the causal agent of gray mould diseases in grapevine, is vastly responsible for substantial economic losses in table and wine grapes production worldwide by negatively affecting plant growth and causing the reduction of grape and wine quality. The conventional approach for pathogen control has been up to date based on synthetic fungicides with good effectiveness against pathogens but a negative impact on the environment. The growing level of harmful residues in the environment and some also detected in wines have led the European Union and many winemakers to limit the application of synthetic fungicides to earlier season. However, with a high risk of disease also late in the season, the need for other solutions is clear. Consequently, more and more research is focused on finding potential alternatives in the form of effective biological control agents. Although there are several reports of yeast’s biocontrol activity, they are up to date still poorly commercialized for such purposes. As the yeasts represent an important part of the grape microflora, competing with other microorganisms (including pathogens) for nutrients and space, we decided to examine the potential of autochthonous yeasts as "green" alternatives in fighting against phytopathogens such as B. cinerea in viticulture. With this aim, we tested the biocontrol activity of 119 different indigenous yeasts belonging to 30 different species of 17 genera against filamentous fungus B. cinerea, the causal agent of grey mould or botrytis bunch rot in grape. The yeasts were screened for putative multidimensional modes of action such as antifungal volatiles (VOC), in vitro inhibition of fungal mycelial growth, competition for nutrients, hydrolytic enzyme activities, and yeast tolerance to fungicides like copper, iprodione and cyprodinil/fludioxonil combination. With a qualitative detection of the hydrolysis activity by using screening methods based on solid medium with chitin or βD-glucosides as substrates, we found that many tested yeasts were capable of producing lytic enzymes with the ability to degrade the cell wall of phytopathogenic fungi and are potentially also able to produce VOCs via hydrolysis of grape glycosides as a result of β-glucosidase presence. Furthermore, we observed the capability of tested yeast to inhibit fungal mycelia growth on plate and assimilation of a wide variety of carbon sources; however, no siderophore producers were detected. In general, the yeasts under observation were tolerant to the tested fungicides. Their fungicide resistance can indeed be regarded as a beneficial trait for potential biofungicide agent (PBA) candidates due to open possibilities of applications and combinations within low input pest management strategies in the vineyard. Finally, a field experiment in Pinot noir and Pinot gris vineyards was designed to study different combinations of optimized canopy microclimate manipulation (CMM) techniques and potential biocontrol agent (PBA) application. In experimental conditions, the ability of PBA’s to maintain appropriate population density for disease prevention was observed. In addition, the grape and wine quality parameters were analysed to observe the possible impact of implemented biocontrol yeast on final products. The biocontrol yeast Pichia guilliermondii ZIM 624 was selected and applied in experimental vineyards based on yeast testing results. We were able to detect and confirm PBA yeast’s suitable density on grapes until harvest. In the case of early defoliation for both varieties lower grape compactness was observed together with lower yield/ plant, regardless of PBA yeast/ no yeast application. Among grape basic quality parameters, the optimized techniques showed a positive effect on sugar content. Still, unexpectedly, in the treatments with biocontrol yeasts some trends toward higher acidity were noticed in Pinot gris.
Ključne besede:sustainable viticulture, Botrytis cinerea, gray mould, yeasts, biocontrol, canopy microclimate manipulation, grapevine metabolite, dissertations
Kraj izida:Nova Gorica
Kraj izvedbe:Nova Gorica
Založnik:R. A. Adesida
Leto izida:2022
Leto izvedbe:2022
Št. strani:VII, 198 str.
PID:20.500.12556/RUNG-7369 Novo okno
COBISS.SI-ID:114217475 Novo okno
UDK:54
NUK URN:URN:SI:UNG:REP:IFPZPZYF
Datum objave v RUNG:07.07.2022
Število ogledov:1714
Število prenosov:132
Metapodatki:XML RDF-CHPDL DC-XML DC-RDF
:
Kopiraj citat
  
Skupna ocena:(0 glasov)
Vaša ocena:Ocenjevanje je dovoljeno samo prijavljenim uporabnikom.
Objavi na:Bookmark and Share


Postavite miškin kazalec na naslov za izpis povzetka. Klik na naslov izpiše podrobnosti ali sproži prenos.

Sekundarni jezik

Jezik:Slovenski jezik
Naslov:Proučevanje potenciala biotske raznovrstnosti kvasovk za razvoj alternativnih biofungicidov v vinogradništvu : disertacija
Ključne besede:trajnostno vinogradništvo, Botrytis cinerea, siva plesen, kvasovke, biokontrola, manipulacija mikroklime grma, metaboliti vinske trte, disertacije


Nazaj