Bananas At Risk Of Extinction Due To Fungus Outbreak, Warn Scientists

Experts caution that the most widely consumed variety of bananas may be on the verge of extinction as a disease outbreak wreaks havoc on this potassium-rich fruit. Cavendish banana is under attack from a fungal infection called Panama disease (Fusarium wilt) tropical race 4. There are several varieties of bananas, but about 47 per cent that humans consume are Cavendish bananas.

"Nobody is even close to solving the problem," Dan Koeppel, who wrote the book "Banana: The Fate of the Fruit That Changed the World", told Business Insider. 

The fungal infection originates in the tree's roots and metastasizes to the rest of the plant. It prevents the plant from absorbing water or conducting photosynthesis. Eventually, the tree dies. 

Some scientists are engaged in genetic modifications to enhance the fruit's disease resistance. However, there is an alternative viewpoint that suggests the ultimate remedy for this issue is for farmers to fundamentally transform banana production practices, moving away from exclusively cultivating a single fruit variety, the media outlet reported. 

Initially identified in Taiwan in 1989, Tropical Race 4, also known as TR4, has subsequently expanded its presence to Australia, followed by India and China, both major global banana producers. It has also made inroads into regions in the Middle East and Africa.

Concurrently, the disease has most recently surfaced in South America, as reported by James Dale, a professor leading the banana biotechnology program at Queensland University of Technology.

"Once it's in a country it's very hard to get rid of it," said Dan Bebber, a biosciences lecturer at the University of Exeter, in 2019.

The fate currently befalling Cavendish bananas has previously afflicted another well-liked banana variety known as Gros Michel.

TR4 infected the banana variety in 1876 and by the 1950s it was completely extinct. Farmers were forced to look for a new variety. In the following years, "Cavendish became the leading export banana replacing Gros Michel because it was immune to TR1," Dale added.

However, some plant pathologists believe that the Cavendish banana will not meet the same fate as Gros Michel. 

"The disease moves slowly, so we have at least a decade before the impact is drastic," Dale said.

Potential remedies encompass genetically engineered strains that exhibit resistance to TR4 and the practice of fruit grafting, which involves transferring tissues between plants to confer distinct attributes, such as resistance to disease.