Leafing through genetic barcodes: An assessment of 14 years of plant DNA barcoding in South Africa

Abstract

South Africa, a global biodiversity hotspot, faces escalating threats to its rich plant diversity, including habitat loss, climate change, invasive species, and illegal harvesting. These threats are further exacerbated by the country's taxonomic impediment, which hinders both conservation and sustainable development efforts. This paper assesses the efficiency of DNA barcoding as a tool for species identification and biodiversity conservation within the South African context. While DNA barcoding offers promising applications in conservation, significant gaps and challenges persist. We provide a comprehensive overview of plant barcoding initiatives in South Africa – by querying the public data portal for plant barcoding records, 12,456 published specimen records encompassing 159 families and ca. 3,449 species were returned. These numbers highlight historical progress, database contributions, technological advancements, and taxonomic coverage. Despite South Africa contributing the third-highest number of Magnoliophyta records to the Barcode of Life Data System (BOLD), significant gaps in endemic families and geographic regions highlight the urgent need for targeted DNA barcoding initiatives and increased collaboration, as only ca. 16 % of the known flora has been barcoded. The underutilisation of BOLD and financial constraints pose significant barriers to expanding plant barcoding records. However, advancements in sequencing technologies offer cost-effective solutions. We advocate for concerted efforts to enhance DNA barcoding utilisation, harmonise databases, and prioritise sampling of underrepresented taxa to effectively preserve South Africa's diverse plant life.