Another bacterial disease is also caused by Macrocystis pyrifera and Micrococcus generally absorb the cultivation of Laminaria. In addition to ice-ice disease, seaweed can also bacterial and fungal disease. Diseases caused by a fungus that attacks the Hydra thalassiiae air bubbles seaweed Sargassum sp. Disease “ice-ice” (some people call it a white spot) is a major constraint Eucheuma seaweed cultivation, primarily due to environmental changes such as currents, temperature and brightness.
Water transparency is very high and the low solubility of nutrients Nitrates in water are also a cause of the disease. Some researchers have reported that some strains of bacteria have been isolated on the thallus where the bacteria is only a secondary cause (secondary impact). Some abiotic factors have been reported to be the cause of the ice-ice disease in Eucheuma farming in the Philippines is the lack of light density, salinity less than 20 ‰, and the temperature reaches 33-35 ° C (Largo et al., 1995).
Diseases of the seaweed is the case in areas with high brightness and is known as the ice-ice with symptom onset spots on the thallus, over time will lose the color to be white and unbroken. This condition is caused due to extreme environmental changes and can not be tolerated, so the plants become weak (unhealthy). If this situation continues, it will lead to crop failure.
White patches (ice-ice) is a disease that arises on the season and the calm sea followed by a weak flow of summer. This disease can damage the crop area until it reaches 60-80% and a duration of 1-2 months (Sulistijo, 2002). From some research on ice-ice disease, the failure of the harvest season in the suspect may be due;
1) Fishermen do not suspend the cultivation activities during disease outbreak
2) The number of herbivore predator fish whose size is relatively small (5-10 cm) such as fish Siganus sp. and Pomacentris sp. when kelp experience stress. These fish eat the shoots that grow on thalli and takes part thalli, the damage done is not significant, but on the wound on the season unfavorable easily infected by bacteria ice-ice.
3) environmental sanitation were not clean (a lot of trash) is also a contribution of the abundance of bacteria around the cultivation.
4) The lack of anticipation of the change of seasons can trigger disease outbreaks ice-ice.
5) Seeds used for many years is not replaced with fresh seed from outside the area, so that the bacteria can easily adapt to physiological conditions seaweed