DNA 'barcode' for tropical trees

Nov 04, 2009
Forest in French Guiana. © G.FORNET/CNRS

In foods, soil samples or customs checks, plant fragments sometimes need to be quickly identified. The use of DNA “barcodes” to itemize plant biodiversity was proposed during the 1992 Rio de Janeiro Summit. Jérôme Chave's team from the Evolution et diversité biologique laboratory has tested this method in the tropical forest where the CNRS Nouragues, French Guiana research station is located. Their study, published in PlosOne, shows that while the identification of plant species has improved considerably, some aspects of this method remain problematic, especially for tropical species.

Creating a large-scale inventory of is essential for the development of conservation strategies. Within the framework of the Convention on Biological Diversity, the use of DNA barcoding was proposed for the identification of plant and animal species. This method consists of using tissue to sequence short DNA fragments which contain a substantial amount of information. These fragments are then compared to a reference collection to identify their origin. In August 2009, after several years of debate, an international consensus headed by the Plant Working Group of the Consortium for the of Life (CBoL) was reached, according to which two DNA markers (two gene regions dubbed rbcL and matK) would suffice to characterize 250,000 plant species.

The team from the Toulouse Evolution et diversité biologique laboratory, in collaboration with Guyanese partners, conducted the first test of this DNA barcoding method in a tropical forest environment. A total of eight candidate barcodes were tested on over 200 tree species sampled at the CNRS Nouragues research station in French Guiana. More than 2,000 DNA sequences were thus generated for this project. The study yielded significant progress in species discrimination. However, identification success did not exceed 70% and one of the two markers proposed by CBoL proved very difficult to sequence.

At the crossroads between basic research and applied research, this work suggests that despite being an invaluable tool for identifying , the international DNA barcoding method poses problems for exclusively tropical plant families. Solving them would, among other things, enable researchers to itemize and track the biodiversity of Amazonian plants much more efficiently.

More information: "Identification of Amazonian trees with barcodes". M-A Gonzalez, C Baraloto, J Engel, SA Mori, P Pétronelli, B Riéra, A Roger, C Thébaud, J Chave. (Published October 16, 2009). PloS ONE 4(10): e7483. doi:10.1371/journal.pone.0007483

Provided by CNRS

Explore further: Tricking plants to see the light may control the most important twitch on Earth

add to favorites email to friend print save as pdf

Related Stories

Identifying Canadian freshwater fish through DNA barcodes

Jun 18, 2008

New research by Canadian scientists, led by Nicolas Hubert at the Université Laval in Québec and published in this week's PLoS ONE brings some good news for those interested in the conservation of a number of highly-endangered ...

Researchers push for standard DNA barcodes for plants

Jul 27, 2009

Two University of British Columbia researchers are part of an international team recommending standards for the DNA barcoding of land plants, a step they hope will lead to a universal system for identifying over 400,000 species, ...

DNA 'barcode' identified for plants

Feb 05, 2008

A 'barcode' gene that can be used to distinguish between the majority of plant species on Earth has been identified by scientists who publish their findings in the Proceedings of the National Academy of Sciences journal today. ...

Barcoding endangered sea turtles

Sep 14, 2009

Conservation geneticists who study sea turtles have a new tool to help track this highly migratory and endangered group of marine animals: DNA barcodes. DNA barcodes are short genetic sequences that efficiently ...

Cracking the species code for plants

Feb 17, 2009

A recent article published in the Botanical Journal of the Linnean Society searches for one or more short pieces of DNA code that could eventually be used in an automated fashion to reliably identify almost all land plant ...

Recommended for you

Getting a jump on plant-fungal interactions

Jul 29, 2014

Fungal plant pathogens may need more flexible genomes in order to fully benefit from associating with their hosts. Transposable elements are commonly found with genes involved in symbioses.

The microbes make the sake brewery

Jul 24, 2014

A sake brewery has its own microbial terroir, meaning the microbial populations found on surfaces in the facility resemble those found in the product, creating the final flavor according to research published ahead of print ...

User comments : 0