Targeted Next Generation Sequencing data for European Green Crab

In the northeast Pacific Ocean there is high interest in developing eDNA-based survey methods to aid management of invasive populations of European green crab (Carcinus maenas). Expected benefits are improved sensitivity for early detection of secondary spread and to assess the outcome of eradication efforts. A new eDNA-based approach we term ‘Targeted Next Generation Sequencing (tNGS)’ is introduced here and shown to improve detection relative to qPCR at sites with lower green crab CPUE values measured by trapping. DNA standards (gBlock) with starting molecule copies that were 10- to 100- times lower than the qPCR limit of detection returned significant numbers of sequencing reads, which in our field assessments translated to a 7% - 10% increase in detection probability from tNGS relative to qPCR at sites with lower CPUE. We also found the number of sequencing reads from tNGS was significantly correlated with green crab CPUE whereas Ct values from qPCR were not. When sources of variati...东北太平洋海域对于开发基于环境DNA（environmental DNA, eDNA）的调查方法以助力欧洲绿蟹（Carcinus maenas）入侵种群的管理具有极高关注度。该方法的预期收益包括提升对二次扩散的早期检测灵敏度，以及评估根除行动的实施效果。本文介绍了一种我们命名为“靶向下一代测序（Targeted Next Generation Sequencing, tNGS）”的新型eDNA检测方法，相较于实时定量聚合酶链反应（quantitative Polymerase Chain Reaction, qPCR），该方法在通过诱捕测得绿蟹单位捕获努力量渔获量（Catch Per Unit Effort, CPUE）较低的采样点中，可提升检测效能。起始分子拷贝数较qPCR检测下限低10至100倍的DNA标准品（gBlock）可产出大量测序读段；在我们的野外评估中，这一结果意味着在CPUE较低的采样点，tNGS的检测概率较qPCR提升了7%至10%。此外我们发现，tNGS产出的测序读段数量与绿蟹CPUE呈显著相关，而qPCR得到的循环阈值（Cycle Threshold, Ct）则无此相关性。当变异的来源