Identificaton of red tide phytoplankton during the winter season in the lagoon of Youngrang, Korea

Abstract

To identify hibernal red tide species in the Youngrang Lake, the present study was carried out quantity / quality analysis of species composition using light- and scanning electron-microscopy as well as molecular analysis using denaturing gradient gel electrophoresis (DGGE). Phytoplankton abundance was 4.2 x 104 cells mL-1, where Cryptomonas sp. was the pre-dominant species (54.5%) and the sub-dominant species were Paulinella sp. (32.3%) and Heterocapsa rotundata (10.7%). In fluorescens for primulin staining, chloroplasts in Cryptomonas sp. and Heterocapsa rotundata were colored in the red indicated by autotrophic, whereas that in Paulinella sp. was in the green by heterotrophic. In DGGE analysis, three bands were amplified and obtained sequences in the DGGE were same with microscopy as mentioned above. Cryptomonas and Heterocapsa rotundata were well known as red tide taxa in coastal, brackish and fresh water. In this study, there was firstly reported that Paulinella sp. was harmful algal blooming species. In Korea, red tide in the lagoon, Youngrang Lake, is not reported. Therefore, studies of red tide species in the lagoon were studied in various focuses, such as outbreak mechanisms, ecology, and physiology, etc.