Developing a non-destructive metabarcoding protocol for detection of pest insects in bulk trap catches

Area of Science:

• Entomology
• Molecular Biology
• Genomics

Background:

• Insect surveillance is crucial for managing invasive species.
• Metabarcoding offers high-throughput identification but requires validated protocols for regulatory compliance.
• Current methods face challenges in identifying all specimens in mixed catches.

Purpose of the Study:

• To develop and evaluate a multi-locus, non-destructive metabarcoding protocol for invasive insect detection.
• To ensure the protocol meets regulatory requirements for invasive species surveillance.
• To validate the protocol's efficacy using target pests and field samples.

Main Methods:

• Development of a multi-locus, non-destructive DNA metabarcoding protocol.
• Validation using mock communities and field-collected samples containing tomato potato psyllid and Russian wheat aphid.
• Comparison of metabarcoding results with traditional morphological identification and confirmatory barcoding.

Main Results:

• The protocol reliably detected target insects in mixed communities, including specimens missed by morphological identification.
• Metabarcoding sensitivity was influenced by community size, primer bias, target loci, and indexing strategy.
• Non-destructive DNA extraction facilitated verification and re-analysis of specimens.

Conclusions:

• The developed metabarcoding protocol is a sensitive tool for detecting invasive agricultural pests.
• Non-destructive DNA extraction is valuable for resolving identification discrepancies and enabling confirmatory analyses.
• Further optimization is needed to address limitations in diversity estimation and enhance sensitivity in complex samples.