Cavendish bananas face extinction and not all experts agree on how to save it – DNyuz

Cavendish bananas face extinction and not all experts agree on how to save it

Each year, humans worldwide eat over 100 billion bananas, most of which are a type called the Cavendish. Perhaps not long.

A fungal disease threatens to wipe Cavendish bananas off the face of the Earth. Some scientists are genetically modifying the fruit to be more resistant to disease.

But the best solution to the problem, some argue, is for farmers to completely overhaul banana production and stop growing only one variety of fruit altogether.

Why Cavendish bananas dominate the global market

There are over 1,000 varieties of bananas, but about 47% that humans eat are Cavendish bananas (Musa acuminata).

Cavendish dominates the global banana market for several reasons. It’s resistant against some major diseases that kill bananas. Two, the bananas have a longer shelf-life. And three, the farmers are able to grow more Cavendish varieties than any other variety on the same land.

“Because of all these reasons, Cavendish becomes a very practical product,” journalist Dan Koeppel, author of the book “Banana: The Fate of the Fruit That Changed the World,” told Insider.

But the Cavendish is under threat from a fungus that infects the plant. The infection is called Panama Disease (Fusarium wilt) tropical race 4.

TR4 infection starts in the banana tree’s roots and then spreads, ultimately disabling the plant’s ability to absorb water or conduct photosynthesis. Eventually, the tree dies as a result.

Panama disease is a serial banana killer

What’s happening to Cavendish bananas has happened before to another popular banana variety called Gros Michel.

According to Insider, the main banana export in the early half of the 20th century was Gros Michel.

But a predecessor to TR4, called tropical race 1, began infecting bananas in 1876. By the 1950s, it had completely decimated Gros Michel farms, forcing banana producers across the globe 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.

In 1997, scientists detected a new strain (TR4) near Darwin, Australia, that infected Cavendish. By 2015, it had spread to the banana farms in Queensland, the largest banana-producing state in Australia.

“Since that time, it has spread from Australia to India and China – the two largest banana producers in the world. Dale, a spokesperson for Insider told Insider that the virus has spread from South America to Africa and Middle East.

How scientists are trying to save the Cavendish

Some plant pathologists don’t believe that the Cavendish banana will meet the same fate as Gros Michel.

“The illness moves slowly so it will be at least 10 years before its impact becomes drastic,” Dale explained.

Also, many scientists are working on TR4-resistant Cavendish or a resistant replacement for Cavendish.

For example, Dale and his colleagues have developed a genetically modified Cavendish called QCAV-4, which they said is highly resistant to TR4.

Another research group led by scientists at the University of Cambridge is exploring grafting as a possible solution. According to the University of Cambridge, grafting tissue of one plant onto another plant can change certain traits of that plant. For example, it could make it more disease resistant.

Another team at the Taiwan Banana Research Institute is attempting a form of natural selection. The team takes Cavendish seedlings and exposes them to TR4. The small portion of seedlings that fair best then go onto additional experiments to ultimately help the Cavendish evolve to become resistant to TR4, absent of genetic modification.

“I can say that the Cavendish export market will not be severely affected before a solution is found,” Dale said.

But some banana experts argue that such solutions won’t work long term.

There’s no single solution to the problem

“It’s true that there is some resistance, but I’d say right now, nobody is even close to solving the problem,” Koeppel told Insider, adding “The answer is going to be the end of monoculture. The answer is variety.”

He suggests that replacing the current banana cultivar with a new disease-resistant variety is a short-term solution because the fungi can also come up with a new and more powerful strain in the future.

The real solution is to mass produce and sell more than one banana variety because the more genetically diverse bananas are, the less likely they’ll be susceptible to diseases, he said.

Plus, it would also reduce the dependence of humans on one type of banana.

“Apples is a great example. Today If I go to any supermarket in the US, I will find between five and 30 apple varieties,” Koeppel said. “Apple growers are going nuts trying to introduce new varieties naturally as well as through hybridization, and genetic modification.”

This reduces the risk of disease, offers more variety to customers, and as a result, “apple growers are still making a lot more money because of this,” he said.

According to Koeppel, bananas are a problem because there is a limited variety and the prices are low.

“If you add variety, the investment will pay off very quickly because suddenly some people will pay $4 a pound for certain bananas,” Koeppel told Insider.

Dale isn’t as sure. “Price is the driver,” of banana sales in his country Australia. He added, “Most people will purchase Cavendish because it is cheap.”

Introducing a wider variety of bananas would not only drive up costs but would also require a major overhaul in how we transport bananas — since you can’t just store them in freezers for long periods like apples, Dale said.

“The export market is dependent on harvesting Cavendish green and then inducing ripening by ethylene gassing. It is carried out during transportation and it’s very controlled. The Cavendish banana is the only one that is targeted. Dale added, “If multiple banana varieties were exported, each of them would likely require specific ripening requirements.” And of course the price would increase.”

There seems to be no single solution to the problem that’s working, so far. Perhaps history is bound to repeat itself and Cavendish will no longer be the banana of choice in the near future.

The post Cavendish bananas face extinction and not all experts agree on how to save it appeared first on Business Insider.