Identification of bacteria in seaweed (Kapapphycus alvarezii) affected by the ice-ice disease in Amal and Tanjung Tarakan waters, Indonesia

The ice-ice disease is caused by abiotic and biotic factors that appear macroscopically in the presence of white and soft parts of the infected seaweed. This disease is a major obstacle in the cultivation of seaweed (Kappaphycus alvarezii). The transmission is very fast and can cause the death of seaweed, resulting in considerable losses in cultivation. Ice-ice disease infection is seasonal, contagious and generally caused by a secondary bacterial infection. The purpose of this study was to identify bacteria that causes the ice-ice disease in K. alvarezii, during the growing season from August to October 2021. A total of five sampling points were used, including four stations in Amal waters and one in Tanjung Pasir Tarakan, Indonesia. Based on the results of the study, five genera of bacteria were identified in the infected samples collected from the five observation stations, namely Vibrio sp., Pasteurella sp., Edwardsiella sp., Plesiomonas sp., and Chromobacterium sp.