Hitting a moving target: Novel genomic resources to identify and trace traded orchids

Abstract

Wildlife trade is one of the largest threats to biodiversity today. To curb the devastating effects of unrestricted trade on species that are vulnerable to overexploitation, international trade is only permitted under strict conditions. The orchid family comprises the largest group of species that are protected under international treaties. In spite of regulations, edible orchid tubers that are used for a popular Mediterranean delicacy called ‘salep’ are traded widely. This thesis explores which species are preferentially sold as salep and how this compares with traditional salep collected decades or even centuries ago. The first chapter reviews the methods available for monitoring (illegal) trade. Based on this, “target enrichment”, which captures genetic information from hundreds of target genes in the genome, was selected as the most promising tool for detecting the species identity of dried and degraded orchid tubers. The second chapter develops custom resources to capture 205 orchid-specific genes, demonstrating their effectiveness in untangling the relationships between over seventy potential salep species. The final chapter deploys these resources by identifying nearly 200 salep tubers, and shows that more species are being harvested over time – a trend that is likely to be unsustainable with negative consequences for local orchid populations.