Sino-German Cooperative Projects in Marine and Polar Science

Diversity and abundances of marine Vibrio species and their phages in aquaculture systems and dispersal in coastal ecosystems in Hainan Island

Aquaculture is one of the most important economic industries in China. The rapid development of aquaculture would pose a huge influence on coastal environments by water exchange with the surrounding coastal system. Vibrios are natural components of marine microbial communities. The composition and abundances of these natural communities will be changed within the aquaculture system. Some of them may become pathogens for aquaculture populations and cause remarkable economic losses. Antibiotics are the main therapeutic tool to control bacterial diseases in marine aquaculture. However, this might increase the risk for the development and distribution of antibiotic resistance within the microbial community. By their connection with the coastal marine environment, potential pathogenic Vibrios may be dispersed and change the natural composition of the Vibrio community in the coastal environment. Some of these species are also known to be pathogenic for humans. This potential negative effect seems of special importance because of the importance of beaches for human recreation. Bacteriophages were suggested to be an attractive alternative to antibiotics for biological control of bacterial diseases in marine aquaculture. Phage therapy has some unique advantages over antibiotics to control infectious diseases caused by bacteria, including high host specificity, self-replication, and low environmental impact. This project aims to investigate the diversity and abundance of marine Vibrio species and their phages in aquaculture systems and dispersal in coastal ecosystems in Hainan Island.

The project includes the four following topics:
1) Diversity and abundances of Vibrio species in coastal environments.
2) Influence of aquaculture systems on the community structures and   distribution of Vibrios in the coastal environment.
3) Diversity of phages specific to Vibrios and their distribution in aquaculture and coastal environments.
4) Biological characteristics of phages specific to Vibrios and their application potential in aquaculture systems.