Coffee is under threat: how scientists are fighting to save it from extinction

Ethiopia is the homeland of arabica coffee (Coffea arabica).Credit: hadynyah/Getty

“A mathematician is a machine for turning coffee into theorems” is a quote often attributed to the late Hungarian mathematician Paul Erdős. The brew is one of the world’s favourite drinks and an essential stimulant for many researchers — but its future is uncertain.

“Coffee is critically threatened by climate change,” says Kassahun Tesfaye, a plant geneticist at Addis Ababa University.

Nearly all the 10 million tonnes of coffee beans consumed annually around the world come from two plant species: the strong and often bitter robusta (Coffea canephora) and the more-delicate-tasting arabica (Coffea arabica). Unfortunately, arabica suffers or dies when temperatures rise just a few degrees1, and robusta requires massive amounts of water and its yields drop drastically in a drought.

Researchers are racing to keep the world’s coffee-drinkers awake — and preserve the livelihoods of the many lower-income-country farmers who grow the cash crop. Solutions vary from improving the resilience of the two main species, to experimenting with relatives in the Coffea genus, to squeezing more coffee out of current crops with clever chemistry tricks.

Cold coffee beans grind smaller

Arabica’s birth

Ethiopians are proud of their country for being the homeland of arabica coffee — and coffee rituals are a social glue across the country’s many cultures, Tesfaye says.

The Ethiopian government has been establishing conservation areas to preserve the natural genetic diversity of the species. It also grows more than 12,000 arabica plants in living collections at the Ethiopian Biodiversity Institute in Addis Ababa and at the Ethiopian Institute of Agricultural Research in Jimma.

The government is betting that these plants will provide the material for breeding — or genetically engineering — arabica cultivars with traits designed to withstand high temperatures and drought. The plants' cells also come with four full sets of chromosomes, rather than the two found in many other Coffeas (or in humans), reflecting arabica's origins from the spontaneous interbreeding of two other species within the past 50,000 years, Tesfaye points out. “I believe we have enough gene pool to fight climate change.”

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