Quality Control Analysis of Eukaryotic Microalga Diversity Based on High-throughput Sequencing in Liaodong Bay

SONG Lun;WU Jing;LI Nan;SUN Ming;DU Jing;WANG Peng;State Key Laboratory of Urban Water Resource and Environment, School of Environment,Harbin Institute of Technology;Key Laboratory of Marine Biological Resources and Ecology,Liaoning province Liaoning Ocean and Fisheries Science Research Institute;

eukaryotic microalga;;high-throughput sequencing;;brown tide;;diversity;;quality analysis;;Liaodong Bay

In order to further optimize the molecular identification technology of eukaryotic microalgae, the quality control method of eukaryotic microalga diversity in Liaodong bay was discussed based on high-throughput sequencing data, such as the sequence clustering level, and the sequencing data volume. The results showed that the high-quality sequence number obtained from each sample was above 87% in Liaodong Bay, and the proportion of bases was above 97% in the sequence number which was used for annotation, indicating that the measured data was accurate and reliable. In the 97% sequence clustering level, the identification of species abundance was more accuracy, and also reduced the overestimation of species diversity. The reasonableness of sequencing data volume was evaluated by using dilution curve and hierarchical clustering curve. When the curve became flat, it indicated that the sequencing data volume was reasonable, so it was not nessary to increase the amount of sequencing data. Furthermore, the sequencing quantity of algae in Liaodong Bay reached a reasonable level no matter on station evaluation or group evaluation. According to the results of high-throughput sequencing, the study compiled the list, distribution and characteristics of phytoplankton in the Liaodong Bay. The list contained 90 kinds of algae, including 7 fish-kill algae, 25 red tidealgae or brown tidealgae, and 21 toxinalgae.