Background: Prasiola japonica is a freshwater green algae species that can only be seen in Korea and Japan. The various conditions necessary for its growth and reproduction have not been fully elucidated. Therefore, in this study, we aimed to investigate conditions related to the growth and reproduction of P. japonica for the purpose of conserving and producing this species. We first examined differences in growth according to various conditions in different habitats to understand the growth environment of P. japonica.
Results: The experimental results revealed that the optimal temperature for growth and reproduction of P. japonica was between 10°C–15°C, and the optimal light intensity was 1,000–1,500 lux. Furthermore, when Provasoli enriched seawater with iodine (PESI) agar was used, the growth of P. japonica was found to be at least 1.5–8 times greater than that of the general Sohan Valley water sample, and it also showed 2–4.5 faster growth rate to reach 30 µm. These results emphasize the importance of PESI agar in the culture of P. japonica, and are expected to be helpful in suggesting ways to utilize and conserve P. japonica resources.
Conclusions: Through these research findings, we suggest new methods for conserving and producing P. japonica, highlight the importance of preserving the P. japonica ecosystem, and explore ways to utilize P. japonica resources. This research promotes the under- standing and protection of P. japonica resources in Korea and beyond, and underscores the need for further research and conservation efforts.

Keywords: cultivation method; life cycle; mass production; Prasiola japonica; species conservation