利用环境DNA技术探测南海西沙鲸类物种多样性

本研究通过提取南海西沙海域水体样本的环境DNA,利用鲸类线粒体12S r RNA和16S r RNA通用引物进行扩增和高通量测序,并结合目视观测的结果探讨环境DNA技术在鲸类物种多样性研究中的应用前景。结果显示,4种通用引物在鲸类鉴定方面具有一定的有效性,利用4种通用引物在西沙海域19个站点的样品中检测到5种鲸类,分别为热带斑海豚(Stenella attenuata)、长吻飞旋海豚(Stenella longirostris)、弗氏海豚(Lagenodelphis hosei)、小布氏鲸(Balaenoptera edeni edeni)和短鳍领航鲸(Globicephala macrorhynchus),采样过程中观测到的3种鲸类分别为:热带斑海豚、长吻飞旋海豚和瑞氏海豚(Grampus griseus)。两种方法检获的优势物种一致,利用环境DNA技术检测到了未被观测到的物种。结合引物Cet-12S和Marver3的检测结果可以涵盖所有站点(n=17)和所有鲸类物种(n=5),表明针对不同基因片段的引物结合使用有利于检测效果的提高。对于检出的鲸类序列和物种数,4种引物之间不存在显著...

Preliminary investigation of cetacean species diversity in Xisha sea area of the South China Sea using environmental DNA technology

This study investigated the application prospects of environmental DNA (eDNA) technology for studying the species diversity of cetaceans. It involves extracting eDNA from water samples in the Xisha sea area using universal primers for amplification targeting cetacean mitochondrial 12S rRNA and 16S rRNA. High-throughput sequencing was conducted. The results were combined with visual observation data to discuss the potential of eDNA technology in cetacean species diversity studies. These results indicated that the 4 universal primers were effective for cetacean identification. Using these primers, 5 cetacean species were detected in samples from 19 stations in the Xisha sea area. The identified species included the pan-tropical spotted dolphin (Stenella attenuata), spinner dolphin (Stenella longirostris), Fraser''s dolphin (Lagenodelphis hosei), Eden''s whale (Balaenoptera edeni edeni), and short-finned pilot whale (Globicephala macrorhynchus). The cetaceans observed during sampling included the pantropical spotted dolphin, spinner dolphin, and Risso''s dolphin (Grampus griseus). The dominant species detected by both methods were consistent, and the environmental DNA (eDNA) technology identified species that were not visually observed. The detection results of primers Cet-12S and Marver3 covered 5 cetacean species and 17 sites where cetaceans were detected, indicating that the combined use of primers targeting different gene segments is advantageous for improving detection effectiveness. There were no significant differences among the 4 primers in terms of the detected cetacean sequences and number of species. Cet-12S exhibited the highest proportion of cetacean sequences and species, accounting for 33.0% and 21.1% of the total population, respectively. In contrast, the other primers detected much lower proportions of cetacean sequences and species, ranging from 0.2% to 0.6% and 2.0% to 4.1%, respectively. In addition, the number of nonspecifically amplified sequences and species detected by Cet-12S was significantly lower than that of the other 3 primers, indicating its high specificity as a universal primer for cetacean eDNA. Compared to visual observation, eDNA technology has advantages such as high sensitivity, efficiency, and cost-effectiveness, making it well suited for studying the species diversity of cetaceans. This study enhanced our understanding of cetacean species diversity in the Xisha Sea area, offering technical insights for cetacean conservation and research.