Enjoy a steaming mug of Arabica or robusta in the morning? Give a high-five, then, to the scientists that have "reanimated" a fungus that kills off those varieties of coffee trees. It may sound counterintuitive, but researchers from Imperial College London have done just that, resurrecting cryogenically frozen samples of the Fusarium xylarioides pathogen behind coffee wilt disease, which has seen at least two serious outbreaks in West and Central Africa—in the 1920s-1950s and the 1990s-2000s—and cost coffee farmers billions, per a release. Via a study published in the BMC Genomics journal, the researchers hoped to discover whether the coffee-destroying fungus picked up genes from a closely related fungus responsible for wilt disease among other crops—including Panama disease in bananas—thereby boosting the destructive abilities of the coffee-specific fungus.
The scientists explain how they "woke up" two strains collected in the 1950s from the original outbreak, which affected a slew of coffee varieties, and then two strains each from the more recent fungi that affected Arabica and robusta varieties specifically. They found the newer, variety-specific strains had larger genomes, with genes strikingly similar to those found in fungi that destroys bananas and other crops. While the transfer of genes from the banana-killing fungus to another species hasn't yet been seen, scientists say coffee and banana plants are often grown next to each other, making it possible the coffee fungus absorbed the hardier genes from its banana-attacking neighbors. The researchers say this new knowledge could help coffee farmers prevent new strains of coffee wilt disease, specifically by planting coffee in a dedicated section separate from other crops or by eliminating plant debris that attracts the related fungus. "Our aim is to replicate this study for many plant pathogens, eventually drawing up a 'rule book' of how pathogenicity evolves," study co-author Timothy Barraclough says in the release. (Read more discoveries stories.)