Endophytes are microorganisms that live inside the plant tissue without causing external symptoms. All plants in nature harbor endophytes. Some endophytes produce and secrete biologically active compounds, known as secondary metabolites, which can help the host plant cope with bacterial, fungal, and other pest pathogens. Endophytes are isolated from aquatic plants and algae. Diseases are detrimental in the aquaculture industry where chemical pesticides and antibiotics are widely used in an attempt to cope with fish pathogens. However, the ability to prevent disease outbreaks in aquaculture is currently extremely limited. Here, we isolated 173 bacterial and fungal endophytes from 16 Mediterranean seaweed and 4 algae from fresh or thermo-mineral water. We found 88 endophytes (51%) with biological activity against four common aquaculture pathogens. Fifty endophytes (29%) caused mortality of at least one of these four pathogens. We identified 23 bioactive endophytes, 18 of which are from the Bacilli class. Our findings suggest that macroalgae from different aquatic environments can serve as a good source of potential biocontrol agents against aquaculture diseases. To the best of our knowledge, there are no published studies demonstrating the use of algal endophytes to control aquaculture diseases. Our study may lead to finding new molecules for use as novel environmentally friendly products that will solve one of the most challenging problems for the growing aquaculture industry: pathogens and pests.
Bibliographical noteFunding Information:
This work was financed by the Chief Scientist of the Israeli Ministry of Agriculture and Rural Development (MOARD); grant number 20-02-0122 and Copia Agro Israel.
The authors would like to thank Mrs. Rita Smirnov and Mr. Tamir Ofek from The Central Laboratory for Fish Health, Nir David, Israel for providing the four-aquaculture pathogens, Dr. Gabi Banet from the Dead Sea-Arava Science Center, Israel for taxonomic identification of the cyanobacterium Leptolyngbya sp. and Ms. Bar Ezra for helping with the PCA analysis. Funding. This work was financed by the Chief Scientist of the Israeli Ministry of Agriculture and Rural Development (MOARD); grant number 20-02-0122 and Copia Agro Israel.
© Copyright © 2021 Deutsch, Gur, Berman Frank and Ezra.
- bacteria and fungi
- disease and pathogen
- environmentally friendly
ASJC Scopus subject areas
- Global and Planetary Change
- Aquatic Science
- Water Science and Technology
- Environmental Science (miscellaneous)
- Ocean Engineering