In 2003 The New Scientist claimed bananas could be extinct in a decade due to the leaf disease Black Sigatoka as well as Panama Disease, caused by a soil fungus that attacks the roots of the plant. The article may seem alarmist, given that we’d have to lose all bananas within the next two years for it to be true, but it shouldn’t be ignored. After all, the Panama disease has struck in a big way before.
Most of the bananas traded today (as much as 99 percent) are of the Musa acuminata variety, commonly known as the Cavendish, and around 100 billion are sold every year. But prior to 1960 the Gros Michel variety (aka The Big Mike) accounted for almost all commercial sales. The problem was that it was susceptible to blights and fungal attacks.
Panama disease killed it off, leading to a global banana shortage and some terrible music. The 1923 musical hit “Yes, We Have No Bananas” is said to have been inspired by a shortage of the Big Mike in the early 20th Century. By 1960 importers were facing financial ruin and (at great cost) they totally re-organised the business, focusing instead on the Cavendish, which was seemingly resistant to the disease. The Big Mike is still cultivated in some places, but as a commercially viable food for export it’s down there with the dodo burger.
And now history is being repeated. While we can spray chemicals to fight Black Sigatoka, the fungicides are becoming increasingly ineffective and the Panama disease has evolved. The Cavendish is now highly susceptible to a new strain, “Panama race 4”, just as the Big Mike was exposed to the original Panama-causing fungus.
One of the reasons it’s such a problem is the way we have altered the fruit for our own needs. Dan Koeppel, author of Banana: The Fate of the Fruit That Changed the World writes: “After 15,000 years of human cultivation, the banana is too perfect, lacking the genetic diversity that is key to species health. What can ail one banana can ail all. A fungus or bacterial disease that infects one plantation could march around the globe and destroy millions of bunches, leaving supermarket shelves empty.”
Since discovering the new strain of Panama disease in Asia in 1992, it has wiped out plantations in Indonesia, Malaysia, Australia and Taiwan, and is now spreading through Southeast Asia. The UN Food and Agriculture Organisation (FAO) has responded by urging producers to promote greater genetic diversity in commercial bananas, as there are over 300 species of banana in existence.
This would undoubtedly help matters. Historically bananas were not the sweet, yellow ones that were, well, banana shaped. They were more like the red and green cooking variety, now generally referred to as plantains. The sweet yellow banana we eat today is a mutant strain that was discovered in 1836 by a Jamaican called Jean Francois Poujot. He found one of the banana trees on his plantation was bearing yellow, rather than green or red, fruit. When he noticed how sweet it tasted straight from the tree, he began to cultivate this variety.
This is significant because one of the main problems is our cultivation process. Modern bananas grown for mass consumption are propagated asexually from offshoots of the plant rather than seeds. According to the FAO, many of the genes that could save the Cavendish may already be lost, and one variety that contains genes that resist Black Sigatoka survives only as a single plant in the botanical gardens of Calcutta.
Given that bananas are grown in over 100 countries, it would be highly improbable that such a disease would spread to all the regions, but there is clearly a problem for the Cavendish. What we may have to do in future is reassess what we consider to be the norm for a banana. And there’s some good news. The Honduras Foundation for Agricultural Research (FHIA) has been crossbreeding bananas for decades in the hope of finding a Panama-resistant strain, and they appear to have finally had some success. The bad news is that the new variety tastes more like apples.
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