Why the next banana you eat might be the last

Banana farmers and fans are being urged to expand their tastes, with fears the popular Cavendish variety might soon be wiped out.

Around half of all bananas sold in the world - and almost all we see in the West - are Cavendish, which is at risk thanks to infections and climate change.

The problem is Cavendish bananas are all clones, so there's no genetic diversity.

 "When you have monoculture, you just have this endless amount of food for the pest," Cardiff University ecologist Angelina Sanderson Bellamy told LiveScience. "It's like a 24-hour buffet."

The Cavendish bananas we know today were developed in the mid-20th century to replace the Gros Michel variety, which had been devastated by disease. But since the 1990s Cavendish bananas have faced threats from fungal diseases, including fusarium wilt and  black sigatoka, raising fears it could be wiped out.

Because they don't reproduce sexually like most plants, Cavendish bananas are slow to evolve. But they're popular because they're good at resisting environmental disasters and quick to recover, according to the UN's Food and Agriculture Organization.

Experts are now looking for potential replacements, should disaster strike.

"We are now making an inventory of all types of bananas found in the local market, mainly for their taste quality, to convince breeders to focus on these," Nicolas Roux, banana genetics researcher, told LiveScience.

"We are in danger, with so much of the market taken up by this one subgroup."

Around 50 billion tonnes of Cavendish bananas are produced every year.

An alternative scientists are working on is finding ways to edit the Cavendish genome to make it more resistant to threats. 

Dr Bellamy said diversifying banana crops into other varieties will end up costing consumers more, but that's the price we might have to pay if we want to keep eating bananas.

"I think there is a crisis in our food system, and I think the [Cavendish] banana is a good example of the way that crisis is manifesting itself."