The role of the secondary attachment disc in the vegetative propagation of Chondracanthus chamissoi (Gigartinales; Rhodophyta)

The reattachment and vegetative growth of tetrasporophytic and cystocarpic fronds of Chondracanthus chamissoi by means of secondary attachment discs was evaluated in vitro. Our results show that both the reattachment of fronds and sprouting of new shoots from secondary attachment discs, occurred in both life cycle phases. We did not observe statistical differences between cystocarpic and tetrasporophytic fronds, which have a similar ability to reattach and produce new shoots. Reattachment was observed after 5 d and reached 54 ± 9% (mean ± S.D.). The new shoots started sprouting 20 d after reattachment, with a growth rate of 5 ± 1% d^-1 (mean ± DS). Our results show that the formation of secondary attachment discs is not only an effective form of reattachment for drifting fronds but also an important strategy to generate new individuals.