The fish egg microbiome: diversity and activity against the oomycete pathogen Saprolegnia

Promotie

The fish egg microbiome: diversity and activity against the oomycete pathogen Saprolegnia

Promovendus ms. Y (Yiying) Liu
Promotor prof.dr.ir. FPM (Francine) Govers
Copromotor prof.dr JM Raaijmakers
dr. I de Bruijn
Organisatie Laboratorium voor Fytopathologie
Datum

ma 13 juni 2016 13:30 tot 15:00

Locatie Aula, gebouwnummer 362
Generaal Foulkesweg 1
362
6703 BG Wageningen
0317-483592

Samenvatting

Atlantic salmon (Salmo salar L.) is threatened by Saprolegniosis, a disease caused by the water mould (oomycete) Saprolegnia. Introduction of beneficial microbes is proposed as a sustainable measure to control Saprolegniosis. Analyses of the microbial community of Atlantic salmon eggs revealed that these eggs house a variety of oomycetes, fungi and bacteria. Two bacteria that were isolated, a Frondihabitans species and a Pseudomonas species, inhibited growth of Saprolegnia and infection of salmon eggs, and growth-inhibiting chemical compounds produced by these bacteria were identified. Among the fungal community, both a quantitative and qualitative difference in the Trichoderma population between Saprolegnia infected and healthy salmon eggs was observed, which suggested that mycoparasitic Trichoderma species could also play a role in Saprolegnia suppression in aquaculture. In conclusion, Frondihabitans, Pseudomonas and Trichoderma species and/or their active chemicals, may be exploited to control Saprolegniosis and probably also other diseases in aquaculture and natural environments.