Scientists pursue wild idea to rescue coffee

Scientists have "rediscovered" a species of coffee which could help future proof the industry against the damaging impact of climate change.

A paper published in Nature Plants reveals that a rare and threatened species from West Africa named Coffea stenophylla－which grows in the wild－is more tolerant of high temperatures than the world's premier arabica coffee bean. The most widely grown variety are robusta coffee beans.

As well as offering a superior flavor, this discovery could provide a lifeline to coffee farmers facing the challenges of the climate crisis. The leading coffee grower and producer in the world is Brazil, followed by Vietnam, Colombia and Indonesia.

The study was compiled by scientists from the London's Royal Botanic Gardens, Kew, the University of Greenwich, the French Agricultural Research Centre for International Development, and Sierra Leone.

A statement from the organization, also known as RBG Kew, explained the coffee's unique qualities mean that stenophylla could soon be grown commercially, but in much warmer places than arabica coffee can.

Aaron Davis, head of coffee research at RBG Kew and lead author of the paper, said future-proofing the supply chain to deal with climate change is going to be needed by the industry.

"Coffee drives a multibillion-dollar global industry, supports the economy of several tropical countries, and provides livelihoods for more than 100 million coffee farmers," he said.

"To find a coffee species that flourishes at higher temperatures and has an excellent flavor is a once-in-a-lifetime scientific discovery. This species could be essential for the future of high-quality coffee."

Coffee farmers are facing challenges such as extreme weather events brought on by climate change and an increasing incidence of ruinous pests and diseases.

Vulnerable supply chain

Scientists have said there has been "limited progress in future-proofing the supply chain under current climate change projections, so finding a climate-resilient coffee crop is considered vital".

In the past, suggested solutions were met with cost challenges and negative impacts on livelihoods and local communities. Finding a coffee plant that can withstand rising global temperatures while retaining taste and flavor has been a challenge for researchers.

Until late 2018, the stenophylla had not been seen in the wild since 1954. RBG Kew said the term "forgotten" is applied to this species because it was once wildly farmed in Upper West Africa and now its use as a crop species is nonexistent. Only a few examples exist in coffee research collections.

The species was found after researchers traveled to Sierra Leone in December 2018, where they discovered a single plant in their main target location. The scientists then located a healthy population after several hours of trekking through dense forest.

Justin Moat, scientist at RBG Kew, who led climate analysis in the paper said: "It is widely known that our beloved arabica coffee in being impacted by climate change, and so the results of the study are extremely exciting. Our analysis shows that stenophylla coffee grows at substantially higher temperatures than arabica, providing the sort of robust differences we need if we are to have any chance of a sustainable coffee sector under climate change."

Coffea stenophylla is classified on the International Union for Conservation of Nature Red List of Threatened Species as "Vulnerable", so efforts are urgently required to safeguard the future of the species in the wild.

RBG Kew said further work is needed to fully evaluate its potential as a climate-resilient, high-value crop species and breeding resource.