The Republic of Korea Institute of Ocean Science and Technology (KIOST) (President: Hong Gi-Hoon) announced that it is the first to discover the resting cysts of Cochlodinium polykrikoides  (C. polykrikoides), the main culprit behind the generation of dense Harmful algal blooms  (red tides) along the coast of Republic of Korea. 

Marine dinoflagellates are a major component of plankton communities and produce resting cysts during their life cycle  and The resting cysts can act as the main contributor for the initiation of red tide.  C. polykrikoides  is one of the dinoflagellates responsible for the red tides that cause tremendous economic losses to the aquaculture industry along the coast of Republic of Korea and in other coastal areas around the world. Before the resting cysts of C. polykrikoides had been discovered, it was difficult to determine the exact mechanism of red tide generation. 

However, a research team led by Dr. Shin Hyeon Ho (senior researcher of KIOST),  detected  various types of resting cysts from sediment samples collected in a coastal area near Tongyeong, where dense algal blooms occurred in 2013, and identified the resting cysts of C. polykrikoides by analyzing the morphology and phylogenetic data of the germinated motile cells. Currently, the motile cells germinated from the resting cysts are carefully preserved and managed at Library of Marine Samples of KIOST.  

Until this discovery, motile cells transported by the Tsushima Warm Current, which is the brach of Kuroshio Current, had been believed to be the main cause of the initiation  of C. polykrikoides red tides in the coastal areas of Republic of Korea, rather than motile germinated from resting cysts. However, this research found that resting cysts play a crucial role for the initiation and diffusion of red tides along the coast of Republic of Korea. 

Dr. Shin said, “The research on the origin of red tide generation can be applied to a variety of areas to reduce economic damages to the aquaculture industry. Also, we have focused our research on the physiology and ecology of motile cells  in order to uncover the mechanism behind the generation of C. polykrikoides red tides, but from now on, we should try to find out where and in what amounts resting spores are diffused near the coastal areas of Republic of Korea, as well as to what extent it contributes to the early generation and diffusion of physiological and ecological traits.”  

This research achievement is significant in that it has given Republic of Korea the opportunity to be a frontrunner in research and development related to the forecasting, prevention, and extermination of C. polykrikoides red tides. Based on these findings, Dr. Shin’s research team plans to thoroughly redefine the mechanism of C. polykrikoides red tide generation and develop technology to prevent and exterminate red tides, which is expected to make a significant contribution to reducing the economic losses that red tides cause to the aquaculture industry.

The related research was conducted by KIOST with the support of the Ministry of Science, ICT, and Future Planning as part of the project titled “Automatic Differentiation System of Red Tides and their Detrimental Effects on Marine Life and the Validity of Control-Applied Technology.” The study was featured in the Journal of Phycology, a world-renowned journal on red tides, under the title “Identification of the resting cysts of Cochlodinium polykrikoides Margalef (Gymnodiniale, Dinophyceae) in Korean coastal sediments.”