eDNA detection of a cryptic insect species using a novel collection technique in crops
Dr Catriona Campbell1, Dr Dianne Gleeson1, Dr Elise Furlan1, Dr Kate Muirhead2, Dr Valerie Caron3
1Institute for Applied Ecology, University of Canberra, Bruce, 2617, 2South Australian Research and Development Institute, Urrbrae, 5064, 3Health and Biosecurity, CSIRO, Canberra, 2601
Abstract:
Sensitive detection techniques are key to inform management practices for invasive and pest species by identifying the pest species’ distribution or identifying the presence of biological control agents that may negate the need for chemical control. Environmental DNA (eDNA) can be used to detect rare, cryptic and invasive species. In this study, we provide a method that expands the application of eDNA within terrestrial systems, using a novel approach of vacuuming. Our study is focused on a cryptic biological control agent of the pointed snail Cochlicella acuta, the fly parasitoid Sarcophaga villeneuveana, which remains within the snail shell for most of its lifecycle, making it hard to detect. Three sites were sampled using traditional surveys and three types of eDNA sampling 1/ crushing live snails, 2/ water washing live snails, old snail shells or vegetation, and 3/ vacuuming live snails or vegetation. An assay was developed to amplify a 129bp fragment of S. villeneuveana, with positive detections recorded in crushed snail samples, water washed live snail, water washed vegetation and vacuumed live snails. Presence of the endoparasitoid was validated by traditional survey techniques conducted at the same time, indicating that both techniques are comparable for detection of the parasitoid. This new technique has great potential to be applied to other insects and environments, particularly cryptic species, pests and biological control agents in crops; making eDNA techniques even easier to use without the need for UV sterilized water and complex filtering systems in the field.
Biography:
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