[Science News] – Rediscovery of a wild coffee tree with key assets for the future of coffee
A team of researchers from Meise Botanic Garden, together with KULeuven and Congolese partners, has just published a major study in Annals of Botany dedicated to Coffea dactylifera, a wild coffee species rediscovered after more than half a century without field observations.
A coffee tree long known only from herbaria, rediscovered after 50 years
This species was collected for the first time in 1936 and for the last time in 1960, and it remained undescribed till 1999 when Elmar Robbrecht and Piet Stoffelen (Meise Botanic Garden) named it Coffea dactylifera and was then known only from herbarium specimens. Its rediscovery in the forests of Yangambi, Bas-Uele and Tshopo (Democratic Republic of Congo) enabled the collection of living specimens, which are now held in Meise and Yangambi. The species is listed as “Vulnerable” on the IUCN Red List, meaning it faces a high risk of extinction in the wild.
A promising wild coffee tree
The study shows that C. dactylifera is genetically close to Arabica coffee (C. arabica). This relationship marks it as a potential useful candidate for breeding programmes, at a time cultivated coffee plants are in need to adapt to increasingly extreme climatic conditions.
While occurring in the hot, lowland forests of Central Africa, where seasonality is low, C. dactylifera shows a compact growth and its leaf traits suggest a drought resistance. However, from an agronomic perspective, its productivity remains low, notably due to the small size of its berries.
Despite this low productivity, its beans reveal an unexpectedly sweet flavour, with notes of brown sugar and a syrupy texture. The species achieved an average score of 78.75 according to Fine Robusta standards.
A strategic resource for the future
Although C. dactylifera is unlikely to be used for commercial bean production, its unique flavour, resilience and genetic proximity to cultivated species make it a valuable resource for breeding programmes.
“This rediscovery reminds us just how precious the wild coffee species of Central Africa are,” the researchers conclude. “They may hold some of the key traits essential for the coffee sector to adapt to a changing climate or increase sensory experience.”