Understanding the Organism: Insights from Chondrus crispus (Rhodophyta) for the Tropical Carrageenan Seaweed Industry

An exploration of the red alga Chondrus crispus was undertaken to demonstrate the importance of understanding the organism that is being studied and how that knowledge might be used in relation to tropical eucheumatoids grown for the carrageenan industry. C. crispus provides an excellent model for this because it is a carrageenophyte, and many aspects of its biology have been extremely well studied over many years. The paper covers differences in the isomorphic life history phases and characters that distinguish the gametophyte from the tetrasporophyte phase, including hypothesizing that the presence of structural colour in the gametophyte phase is a protective mechanism of the reproductive structures against damaging UV. It also considers the value of studying the composition of the holobiont (host and all associated prokaryotes and eukaryotes) in relation to morphology and phenology. Eukaryotic green algal endophytes are discussed, and how differences in the host vegetative morphology of C. crispus and eucheumatoids influence penetration by these endophytic algae is discussed. Resolving eucheumatoid life histories is proposed as a means of working towards new knowledge and strains to improve cultivation. Whether new UV protective materials can be engineered based on the multilayered lamellae that produce structural colour in C. crispus is contemplated. It is concluded that traditional approaches are valuable in understanding the organism and, in conjunction with state-of-the-art techniques, provide a potentially powerful tool with which to address the long-term future of the eucheumatoid seaweed industry.