Monocropped Bananas Flirting with Extinction
In a small market on the South Pacific island of Raiatea, the women laughed in astonishment when I told them we had only one variety of banana in Canada. As I spoke to them in fractured French, they offered me a tiny brown-skinned banana with a buttery texture. By the time our conversation ended, they had given me samples of half a dozen varieties, assuring me there were lots of others, though nowhere near as many as when they were girls.
Now the Cavendish, the sole banana widely available in North America, may disappear from our grocery shelves. In an interview for National Public Radio, banana expert Dan Koeppel talkes about the impact of monoculture and why our insisting on more varieties may be the only thing that will save the banana split.
The last monocropped banana, the tastier Gros Michel, succumbed to Panama disease (a fungal wilt) during the first half of the 20th century. That’s when the Cavendish came to the fore, because of its resistance to the blight and other common banana diseases.
Writing in The Scientist, Koppel describes the work of Randy Ploetz (Tropical Research and Education Center, University of Florida), who discovered in the late 1980s that a new strain of Panama disease was attacking the Cavendish. Called Tropical Race 4, it “has spread across Asia, into the Pacific, and to Australia, where it has devastated the island country’s banana industry.”
Ploetz predicts it will hit America’s banana supplier, Latin America. No one can say when it will arrive, but it can spread via “no more than a speck of dirt on a shoe or a tool.” Randy Ploetz has developed a means of fighting Race 4 when it arrives in Latin America, but concedes it is a stopgap solution. It will buy time while other commercially viable varieties are developed or the Cavendish is genetically modified to resist the disease.
The long-term solution is biodiversity. Koppel writes, “A more diverse banana harvest would allow farmers to isolate susceptible bananas, surrounding them with more resistant varieties. If the solution ends up being a Cavendish stand-in that is resistant to both strains, on the other hand, the predicament of the banana monoculture—with its vulnerability to old, new and yet-to-be discovered pathogens—would continue.
So next time you pick up a bunch of bright yellow bananas, ask the produce manager for more variety. Your banana split might just depend on that.
Photos from Cathryn Wellner