Humans Risk Killing Off One-in-Five of All Plant Species
Examples of invasive species. Image: RBG, Kew


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Humans Risk Killing Off One-in-Five of All Plant Species

Luckily, we’re still finding 2,000 new species every year, but we need to act now to help conserve them.

Twenty-one percent of the world's plant species—essential to food and medicine supplies—are threatened with extinction, according to a report published Tuesday by the Royal Botanical Gardens (RBG) in Kew, London.

But there's hope: It's not too late to remedy the solution, and researchers are still finding as many as 2,000 new species every year.

The first annual "State of the World's Plants" report took a year to produce and involved more than 80 researchers.


"It provides a basis that can inform policy makers and researchers, what the major challenges are and where we should be putting our efforts in order to conserve plant species," said Monique Simmonds, Kew Garden's deputy director of science, over the phone.

She added that while there were various reports on the state of the world's turtles or mammals, to date, nothing similar existed for plants.

Dendrobium cynthiae—a species among the new orchids discovered in 2015. Image: Steve Beckendorf

There are currently 391,000 vascular plants of which 369,000 are flowering plants known to science. The report found that 31,000 plant species have a documented use for medicines, food, and materials.

Some of the most spectacular discoveries from this year include a 1.5 metre-tall carnivorous bug-eating plant called Drosera magnifica found via Facebook in Brazil, and a close relative of the sweet potato (Ipomoea batatas) in Bolivia that could offer an alternative option to the regular spud in the future.

Plants species face extinction owing to the destruction of their habitats for farming, deforestation, building works, climate change, as well as disease and invasive species.

So far the researchers have sequenced the whole genomes of 139 vascular plant species and put them online. Similar to the UK's Human Genome Project that seeks to give a better understanding of the roles of different genes, the researchers at Kew are keen on chronicling the genomic makeup of different plant species.

Drosera magnifica—a bug-eating plant found in Brazil in 2015. Image: Paulo Gonella

"The genomic makeup becomes important when you're looking at traits of disease-resistance to understand how to improve yield, or improve tolerance to different environmental conditions," said Simmons, noting that genome differences allowed some plants to withstand extreme environmental weather conditions where others could not.

The researchers know that their report only covers the bare essentials, but they're hoping that it will make a few more people aware of just how important plants are.

"We wouldn't be having this conversation if plants didn't exist," said Simmonds. "They provide us with oxygen, food, are a source of clothing, and down the food chain they feed animals."