Study on biomass evaluation method of Lutjanus erythropterus based on eDNA technology
Reliable abundance information is the foundation for managing aquatic resources.But it is full of challenges to capture the distribution of rare species through traditional methods.Environmental DNA(eDNA)can produce quantitative estimates of fish abundances,but the precision varies greatly depending on the species and system.Therefore,it is necessary to evaluate its performance and investigate how fish biomass affects eDNA dynamics on a case-by-case basis.Lutjanus erythropterus is an important marine economic fish in the South China Sea,and its wild resources have been declining greatly in recent years.Environmental DNA technology is a new technology for sensitive,low-cost and non-invasive species monitoring.It has great potential for applications in the detection of endangered and invasive species.In order to establish a real-time quantitative PCR(qPCR)method to detect Lutjanus erythropterus,eDNA primers and TaqMan probes were designed based on Cyt b gene sequence in mtDNA in this study.The qPCR method for detecting Lutjanus erythropterus was established by PCR amplifying Cyt b gene sequence and constructing standard plasmid with serial dilution of standard plasmid as template.Subsequently,the sensitivity,specificity and application of the method were evaluated.The results showed a strong linear relationship(R2=0.999 4)between the cycle threshold value(Ct)of the qPCR assay and the logarithm of standard plasmid concentration.The amplification specificity analysis showed that the method could specifically detect Lutjanus erythropterus.Then,a positive correlation(R2=0.56-0.87)was detected between eDNA concentration and biomass of Lutjanus erythropterus in water samples in aquariums with different biomass of Lutjanus erythropterus.In addition,after the removal of Lutjanus erythropterus,the copies of eDNA were negatively correlated with time,and its retention time in water environment was about 20.The results of water samples before and after the enhancement and release of Lutjanus erythropterus showed that the concentration of Lutjanus erythropterus eDNA in the water increased significantly after the release.In this study,we find that the DNA primer and Taqman probe can be applied to the qualitative detection of Lutjanus erythropterus in water with high specificity,and it is also accurate in applying eDNA technology for biomass assessment of Lutjanus erythropterus.These results demonstrate that the eDNA analysis method is a potential tool to reflect the biomass of Lutjanus erythropterus in the wild,which can provide a basis for assessment of artificial release effect and resource management of Lutjanus erythropterus in the future.
万方数据
维普
