Establishing a Standard DNA Barcode for Land Plants (project completed 2007) 

Deciding which short sequences of DNA can be used to identify plants

Kew staff contributed to this themed issue of Philosophical Transactions of the Royal Society B (vol. 360, 2005) following the 1st international DNA barcoding conference, held in Feb. 2005, at the Natural History Museum, London.

The Consortium for the Barcode of Life (CBOL) was established in 2004 with the goal of enabling the identification of all plant and animal species using standardized short DNA sequences. CBOL has been making considerable progress with animal species using the mitochondrial cytochrome oxidase 1 gene (CO1 or cox1), which also promises to be a useful approach in fungi and at least some algae. However the CO1 gene cannot be used with land plants due to their low rate of sequence divergence for mitochondrial DNA in general. This 18 month project aimed to identify potential plant DNA barcode regions, develop universal primers for them, and 'ground test' them on a range of plant groups for which complete or near complete species level sampling is available. Infraspecific studies were also performed to ascertain the value of DNA barcodes as a tool for species delimitation.

Other associated projects such as DNA banking in South Africa, Orchid Monitoring in Costa Rica and barcoding the flora of the Kruger Park, South Africa, focused on the application of the DNA barcode to biodiversity studies and species identification in specific geographical regions.

The outcome of the project was a convergence of the plant diversity community on a standard barcoding system for all land plants. This will have a wide range of applications including: biodiversity studies, forensics, authentication of herbal medicines and foodstuffs, and monitoring international trade in protected species.

Update: In 2009 a proposal was put forward to CBOL by the Plant Working Group for a standard barcode for land plants and published in PNAS:

• CBOL Plant Working Group (2009). A DNA Barcode for Land Plants. PNAS 106 (31): 12794-12797.