London: Barcode gene opens up cataloguing for plants

Research lead

A barcode gene that can distinguish between the majority of plant species has been identified by scientists from the Royal Botanic Gardens, Kew, and Imperial College London, working in collaboration with researchers at the universities of Johannesburg and Costa Rica.

The gene, which can identify plants from a small sample, could provide a new way of cataloguing plants in species-rich areas such as rainforests. It could also lead to accurate methods for identifying plant ingredients in powdered substances, such as in traditional Chinese medicines, and help to monitor and prevent the illegal transportation of endangered plant species.

The team behind the discovery found that DNA sequences of a gene called matK differ among plant species, but are nearly identical in plants of the same species. The matK gene could thus provide a way of distinguishing between plants, including closely related species that may look the same to the human eye.

The researchers, led by Vincent Savolainen, dual appointee at Imperial College London's Department of Life Sciences and the Royal Botanic Gardens, Kew, carried out two large-scale field studies, one on the exceptionally diverse species of orchids found in the tropical forests of Costa Rica, and the other on the trees and shrubs of the Kruger National Park in South Africa.

Using specimens collected from Costa Rica, the researchers were able to use the matK gene to identify 1,600 species of orchid. They also discovered that what was previously assumed to be one species of orchid was actually two distinct species.

In the long run the aim is to build on the genetic information his team gathered from Costa Rica and South Africa to create a genetic database of the matK DNA of as many plant species as possible, so that samples can be compared to this database and different species accurately identified.

“In the future we’d like to see this idea of reading plants’ genetic barcodes translated into a portable device that can be taken into any environment, which can quickly and easily analyse any plant sample’s matK DNA and compare it to a vast database of information, allowing almost instantaneous identification,” says Savolainen.