DNA sequences of the gene, named matK, are nearly identical in plants of the same species.
The findings were published last month in the Proceedings of the National Academy of Sciences of the United States of America.
Co-author Vincent Savolainen, a researcher at Imperial College London and the Royal Botanic Gardens (RBG), Kew, said: “Now we have isolated the matK gene on a DNA barcode we could distinguish between species from just a small fragment of leaf.”
The research team, including collaborators from the universities of Johannesburg and Costa Rica, aims to create a genetic database of matK DNA. Scientists would then compare samples to this database and be able to identify them.
The method will make field work in threatened habitats easier. Savolainen said: “In future we’d like to see this idea of reading plants’ genetic barcode translate into a portable device… which can quickly and easily analyse any plant sample’s matK DNA… allowing almost instantaneous identification.”
He suggested the method could be used by customs officials checking if plant species were being transported illegally or for identifying plant ingredients in powdered substances such as medicines.
Savolainen added: “But it’s not the end of the story. The matK gene appears in 90 per cent of plant species. Yet there are still 10 per cent that are problematic.”
Minister for climate change and biodiversity Joan Ruddock said: “This is a great breakthrough that could save many endangered plants. I congratulate everyone involved in this project, which could have huge benefits for plant identification and conservation.”
The project was funded by the UK Government Defra’s Darwin Initiative, the universities of Johannesburg and Costa Rica, the South African National Research Foundation, RBG Kew and the Royal Society.