The world's favourite banana is named after a duke, and it is a clone in danger.
The Cavendish banana is named after the 6th Duke of Devonshire, whose gardener Joseph Paxton grew it at Chatsworth in the 1830s. It replaced an earlier favourite, the Gros Michel, after a fungus wiped out plantations. Now the same kind of disease threatens the Cavendish too.
Around 1834, William Cavendish, 6th Duke of Devonshire, received a shipment of banana plants from Mauritius. His head gardener, Joseph Paxton, raised them in the glasshouses at Chatsworth, described the plant as Musa cavendishii, and won a Royal Horticultural Society medal for it in 1835. Chatsworth bananas were later sent to the Pacific, and in 1888 bananas of the Dwarf Cavendish type were imported from the Canary Islands into England, though whether the Canary plants came from Chatsworth is disputed.
For decades, though, the world's export banana was another variety, the Gros Michel or 'Big Mike', prized because its thick skin resisted bruising and its dense bunches were easy to ship. It was grown on huge plantations in Central America. Then Panama disease, a wilt caused by a soil fungus, devastated those plantations, and by the 1950s and 60s exporters switched to Cavendish cultivars, which grew in the infected soils. The Gros Michel had more of the flavour compound used in artificial banana flavouring, but the popular idea that the flavouring was modelled on it is a myth.
The deeper problem is how bananas are grown. Cavendish plants are seedless and cannot reproduce sexually, so every plant is a clone, propagated from cuttings. With so little genetic diversity, planted in vast monocultures, a disease that can kill one can kill them all. The Cavendish now makes up around 99 per cent of banana exports to developed countries.
It was assumed to be resistant to Panama disease, but a new strain, Tropical Race 4, began attacking Cavendish in Asia by 2008 and was found in the Americas in 2019. No fungicide is effective against it. Conventional breeding has not yet produced a replacement with the Cavendish's flavour and shelf life; in 2017 researchers in Australia developed a genetically modified Cavendish resistant to TR4, though such crops are banned in some countries.
Source: Wikipedia — Cavendish banana · Text summarised from Wikipedia (CC BY-SA 4.0)
