Synthetic antifungal peptides for controlling brown spot of pear caused by Stemphylium vesicarium. Activity, mode of action and field evaluation

Brown spot of pear is a fungal disease caused by Stemphylium vesicarium. Currently, the disease control efficacy is limited, due to the characteristics of disease and the reduction of the allowed fungicides. Therefore, this thesis is focused on finding new compounds to be applied alternatively or as...

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Detalles Bibliográficos
Autor: Puig Garcia, Mireia
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2015
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/387564
Acceso en línea:http://hdl.handle.net/10803/387564
Access Level:acceso abierto
Palabra clave:Antimicrobial peptides
Pèptids antimicrobians
Péptidos antimicrobianos
Perera
Pear
Peral
Brown spot
Estemfiliosi
Estemfiliosis
Stemphylium vesicarium
Fungicides
Fungicidas
Integrated pest management
Gestió de plagues integral
Gestión integral de plagas
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631/635
Descripción
Sumario:Brown spot of pear is a fungal disease caused by Stemphylium vesicarium. Currently, the disease control efficacy is limited, due to the characteristics of disease and the reduction of the allowed fungicides. Therefore, this thesis is focused on finding new compounds to be applied alternatively or as a complement to the existing fungicides. Thus, twelve synthetic antifungal peptides selected from CECMEL11 library were evaluated in vitro against S. vesicarium. The most effective peptide was BP15 with a minimum inhibitory concentration (MIC) of 10 µM. Moreover, the peptide reduced significantly the disease severity in both ex vivo assays and under field conditions. The mechanisms of action of BP15 were studied. It was determined that the peptide permeabilizes the fungal cell membrane and it is internalized by the cells of germ tubes and hyphae of S. vesicarium.