Objective The study aims to explore the composition, sequence number and diversity of microbial community in Zhuhai Wailingding Marine Ranch, analyze the sensitivity and reducing power of eDNA technology, with a view to providing references for the management and maintenance of ecosystem in Zhuhai Wailingding Marine Ranch.

Method In September 2021, 9 stations were set up in Zhuhai Wailingding Marine Ranch to sample at 2 m below the surface water for pretreatment, DNA extraction, PCR amplification, and high-throughput sequencing to analyze the composition of microbial species, the density and abundance of microbial resources, and determine the dominant species.

Result A total of 30 species of microorganisms in Zhuhai Wailingding Marine Ranch were detected by eDNA technology, and 5 phyla, 7 classes, 14 orders, 19 families and 26 genera were identified, and a total of 779 706 Operational Taxonomic Units (OTUS) were detected. The Proteobacteria was the absolute dominant phylum accounting for 75.06%, followed by Bacteroidetes (11.35%), Firmicutes (5.28%), Planctomycetes (1.91%), and Actinobacteria (1.06%). There were 7 dominant species, which were Pseudoalteromonas, Marinobacter, Moraxella, Psychrobacter, Vibrio alginolyticus, Halomonas and Sphingobacterium. The dominance of Vibrio alginolyticus reached 0.19, which was the absolute dominant species, followed by Moraxella and Pseudoalteromonas reaching 0.134 and 0.127, respectively, which were the main dominant species.

Conclusion The study reveals the microbial community information of the Zhuhai Wailingding Marine Ranch, explores the application of eDNA technology in marine ranch, and verifies the efficiency and sensitivity of this technology, providing basic data and scientific reference for future research on marine ranching microorganisms.