Molecular Identification and Cold Storage of Ten Planktonic Diatoms Isolated from Port of Taichung

• Main Authors: Yi-Ting Wu, 吳宜庭
• Other Authors: Min-Ying Wang
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/65221259423550349478

碩士 === 國立中興大學 === 生物科技學研究所 === 102 === Diatom is the major group of unicellular algae with more than 200 genera and approximately 100,000 species. Identification of a diatom is generally based on their morphological features. However, due to limited morphological differentiation and similarity, unknown diatoms are very difficult to be identified. Recently, a DNA barcode, i.e., a short genetic marker inside 18S ribosomal DNA (named V4 region), has been shown to be a rapid and reliable marker for the identification of diatoms. In this study, 10 centric diatoms (TPC3, 4, 5, 6, 7, 8, 10, 11, 13, 14) isolated from Taichung Port were identified by comparing sequences of the full-length and the hypervariable V4 sub-region of the 18S rDNA gene as well as by characterizing their morphological features of the silica frustules obtained using scanning electron microscope (SEM). The identified diatoms included Rhizosolenia setigera (TPC3), Thalassiosira rotula (TPC4), Thalassiosira lundiana (TPC5), Thalassiosira tenera (TPC6), Thalassiosira minima (TPC10), Cyclotella meneghinana (TPC7), Skeletonema tropicum (TPC11) and Odontella sinensis (TPC14) and the 18S rDNA sequence of Chaetoceros sp.(TPC8 and 13) were first published in our study. Additionally, a simple and cost-effective way to preserve the isolated diatoms at 4°C in darkness (cold storage) was developed. The results demonstrated that all ten isolated diatoms can be preserved by this method for at least one month. In summary, ten centric diatoms isolated from Taichung Port were identified and the cold storage developed here can be applied for the long-term preservation of these diatoms for further investigation.