Abstract

The cultivation of bivalve molluscs in controlled systems requires an adequate control of mortalities in larval stages due to bacterial infections. In this work, the activity of marine bacteria from coastal area of the Arauco Province, Chile to be used as a potential biocontroller in hatchery was investigated. Sampling of different matrices commonly associated with bivalve molluscs in their natural state was carried out and marine bacteria were isolated. The ability of these bacteria to inhibit three pathogenic bacteria normally associated with the culture of bivalve molluscs, Vibrio anguillarum, Vibrio splendidus and Vibrio parahaemolyticus was evaluated. In addition, a phenotypic characterization of the inhibitory strains was carried out, considering their properties of innocuousness and growth, for the practical use of these strains in culture systems. Of the 70 isolated bacteria, three strains were able to inhibit at least one bacterial pathogen and they were able to growth in seawater. The phenotypic characterization of these strains made it possible to identify them as belonging to the genus Vibrio and Pseudomonas. One strain was totally innocuous according to the characteristics evaluated in vitro. In conclusion the selection of bacteria with inhibitory and innocuous properties for a potential biocontrol in bivalve mollusc cultures is feasible in Arauco Province.