Secondary attachment discs: a new alternative for restoring populations of Chondracanthus chamissoi (Gigartinales, Rhodophyta)
When facing the growing, international demand for the species Chondracanthus chamissoi as a source of carrageenan and for human food consumption, it is very important to generate new aquaculture techniques that allow for its repopulation, maximizing biomass yield whilst reducing the pressures on existing small, natural populations. This paper describes the use of secondary attachment discs (SAD) as a new vegetative propagation technique. It involves the following two stages: i) Tying the tetrasporophytic and cystocarpic fronds to natural substrates (shells and rocks), the conditions generated in the tanks allowed for quick SAD formation (12 days of experimentation), and ii) The maintenance of SAD under normal conditions (at sea for 83 days). The results indicated a quick formation of SAD, a high capacity of persistence (40%), the growth of new apices (4% d-1), quick substrate colonization through colonization discs (SADc), and the formation of reproductive structures. As a result, SAD is therefore proposed as both an innovative way to achieve the recovery of the now reduced natural beds of C. chamissoi and as an alternative to traditional methods of vegetative culturing for a species of high commercial interest.