Data for: Environmental DNA storage and extraction method affects detectability for multiple aquatic invasive species

Environmental DNA (eDNA) refers to genetic material released by organisms
into their surrounding environment. Collecting and identifying eDNA has
gained popularity for monitoring and surveillance of aquatic invasive
species. Invasive species management is most successful when an invasion
is identified early while population size is likely to be low,
highlighting the importance of eDNA detection sensitivity. Various factors
influence DNA yield recovered from environmental samples. Environmental
DNA storage and extraction methods, for example, can be adjusted to
maximize DNA yield, thereby improving detectability. In this study, we
compared the performance of two eDNA storage and extraction methods in
detecting three common aquatic invasive species (Bythotrephes longimanus,
Dreissena polymorpha, and Faxonius rusticus) across five natural
ecosystems of Minnesota, United States. One method involved storing
filters in 95% ethanol (EtOH) and extracting DNA using a DNeasy PowerSoil
Pro Kit (Qiagen, Hilden, Germany), whereas the other method used cetyl
trimethylammonium bromide (CTAB) for storage and a
phenol–chloroform–isoamyl (PCI) procedure for DNA extraction. We also
investigated the effect of DNA extract volume (1 μL relative to 3 μL) in
qPCR reactions on eDNA detections for the commercial kit method. The
CTAB‐PCI method yielded significantly more positive detections, across all
three species, compared to the EtOH‐Qiagen method. Moreover, we found that
using 1 μL of DNA extract in qPCR reactions was equally effective as using
3 μL. To improve detections of aquatic invasive species, we recommend that
researchers store eDNA sample filters in CTAB or a similar lysis buffer
such as Longmire's solution and extract with PCI when feasible, but
note that lower extract volumes might be used without negative effect when
either increasing technical replicates or repurposing samples for the
detection of multiple species.