Dr Aaron Davis, Head of Coffee Research at Kew, said: "Among the coffee species threatened with extinction are those that have potential to be used to breed and develop the coffees of the future, including those resistant to disease and capable of withstanding worsening climatic conditions".
They include wild Arabica, a species from Ethiopia that has been cultivated to provide 60% of the multibillion-pound global trade in coffee but which is assessed as endangered largely as a result of climate change.
Davis added that coffee plants grow in very specific natural habitats, so rising temperatures and increased rainfall brought by climate change can make coffee impossible to grow in places the plants once thrived.
The study found that 75 of coffee species are now threatened with extinction, 13 of which were listed as "critically endangered".
DAVID UNWIN STUFFSome 75 wild coffee species are considered threatened with extinction the study said
Many of these wild coffees do not taste good to drink, but may contain genes that can be harnessed to help coffee plants survive in the future, amid climate change and emerging diseases that attack coffee trees.
"As a coffee drinker you don't need to worry in the short term", said Davis. "In another way, it's hardly surprising because a lot of species are hard to find, grow in restricted areas. some have a population only the size of a football pitch".
The analysis was based on the scientists' examination of the 124 known coffee species, and an assessment was produced for the International Union for Conservation of Nature, which publishes the global Red List of threatened species.
Arabica, which has been harvested for millennia in Ethiopia and South Sudan, is without question the most popular, making up roughly 60 to 70 percent of all coffee sales worldwide.More news: Microsoft Pledges $500 Million to Ease Seattle Housing Crunch
"Given the importance of Arabica coffee to Ethiopia, and to the world, we need to do our utmost to understand the risks facing its survival in the wild", said Dr Tadesse Woldemariam Gole, of the Environment and Coffee Forest Forum in Addis Ababa. "With so much deforestation going on around the world, wild coffee species are being impacted at an alarming rate". Two exceptions are arabica, which has been farmed for hundreds of years in East Africa, and robusta, which has gone from the wild to one of the world's most important commodities in the past 100 years.
They found that almost a third of all wild Arabica species were grown outside conservation areas.
The researchers called for a major commitment from countries that grow coffee, particularly African countries such as Ethiopia and South Sudan, to "develop and conserve their wild coffee resources [supported] by the global development and conservation communities".
The multi-billion-dollar coffee sector is founded on, and has been sustained through, the use of wild coffee species, researchers said.More news: Pundit Questions Higuain Transfer to Chelsea
It had not been seen in the wild since 1954, and has all but vanished from coffee plantations and botanic gardens.
What are crop wild relatives? Finding coffee among thousands of other plants was extremely hard, he says. Another 38 closely related species can cross-fertilise commercial coffees through pollen transfer.
Overall, the two new studies present a dire vision of coffee's future-or lack thereof.More news: Arsenal's Alex Iwobi surprised by Petr Cech retirement