Ice-ice

Ice-ice is caused when changes in salinity, ocean temperature and light intensity cause stress to seaweeds, making them produce a "moist organic substance" that attracts bacteria in the water and induces the characteristic "whitening" and hardening of the seaweed's tissues.

[2] The disease is known from seaweeds including Kappaphycus alvarezii and Eucheuma denticulatum, economically important sources of carrageenan.

[4] Analysis has been performed to determine the pathogens affecting the Gracilaria verrucosa and Kappaphycus alvarezii seaweeds.

Morphologic and phenotypic characteristics (16s RNA analysis) showed that the isolates from diseased Gracilaria belong to various genera: Vibrio, Chromobacterium, Flavobacterium, Pseudomonas, and Achromobacter.

Some treatments have been investigated to cure these ice-ice infections, the green algae Caulerpa racemosa seems to inhibit the action of the most part of these pathogens.