People consume 100 billion bananas a year. For many of us it was one of the first solid foods we ate. We are so in love with bananas that we wrote songs about it: Oddly enough, bananas are mentioned in music more than any other fruit.
And if we discovered that someday in the not too distant future? Will this familiar staple disappear from the breakfast table? The most prevalent subgroup of bananas – the Cavendish, which accounts for the largest part of the world market – is infested with insect infestation, decreasing soil fertility and climate change. However, by far the greatest danger are two plant pathogens making their way through huge monoculture plantations (large-scale individual cultures) of this fruit worldwide. "We are in danger as this subgroup has so much market," said Nicolas Roux, senior scientist at Bioversity International in France and team leader of the organization's banana genetics resources.
Bananas are doomed to fail ̵
There are thousands of varieties of bananas worldwide, but over time, few have been selectively bred for commercialization. Prior to the Cavendish strain, which we consume frequently today, this breeding process resulted in the exceptionally large, creamy and sweet banana called Gros Michel. The fruit was loved all over the world. In the 1950s, as the banana plantations expanded to meet the growing global appetite, a strain of the Fusarium Wilt soil fungus – known as Tropical Race 1 – began to benefit from the abundance that spread throughout the farmland. In response, the breeders developed a more resilient plant that could replace the beating Gros Michel – and so the robust Cavendish banana was born.
The Cavendish has colonized the global market like no banana before. Despite hundreds of banana types around the world – some no bigger than a finger, others with big crispy seeds or red skin – the perfect Cavendish in many parts of the world is everything we know. "In Western countries, the vast majority of the bananas we eat come from the same Cavendish subgroup," Roux told Live Science. Worldwide, this variety accounts for almost 50% of production.
So, when? In the 1990s, a new species of Fusarium developed, infecting Cavendish farms. People began to worry that the reign of this banana could also be short-lived. The variety called Tropical Race 4 gets into the trunk, interrupts the water supply of the plant and finally kills it. The pathogen can not be treated with fungicides – so it lives on in the soil.
Angelina Sanderson Bellamy, an ecologist at Cardiff University in Wales, said the way we grow bananas is an accomplice to these threats. United Kingdom, which deals with sustainable agricultural systems including banana plantations. "If you have monoculture, you only have that endless amount of food for the pest – it's like a 24-hour buffet," she said. Pathogens breed on these crops, and huge farms fuel their spread across vast tracts of land.
Another weakness of the Cavendish bananas is that they are asexually bred – so each plant is simply a clone of the previous generation. This means that pathogens spread like wildfire: Without genetic variation, the population is not threatened.
There is also the spread of another fungal disease, the black sigatoka, whose spores migrate through the air, infecting plants and reducing fruit yields. Climate change also supports the spread of this fungus. The increase in the weather conditions favorable for black sigatoka has increased the risk of infection since 1960 in some parts of the world by almost 50%. And while this infection can be treated with a fungicide, farmers need to use it up to 60 times a year, Roux said. "It's terrible for the workers there and terrible for the environment." [Where Do Fruit Flies Come From?]
Fusarium, in particular, has withered banana plantations throughout Asia – including China, India and Taiwan – in parts of Australia and East Africa. Many now fear that it will spread to important exporting countries in South America like Ecuador – which could mean the end of the Cavendish harvest. "There is a great risk that it matters where many large Cavendish plantations are grown as monocultures for export to Western countries," said Roux.
Bananas on the Edge
Faced With This Terrible Prediction, Can We Bring Bananas Back From The Abyss? Well, there are not really any bananas that need to be saved. Several hundred varieties of this fruit thrive successfully around the world, and some are even resistant to Fusarium wilt. It is only the well-known Cavendish that is so threatened – and there is a real possibility that the Cavendish will follow the path of the Great Michel when the Fusarium reaches South America. For this reason, a major focus of Roux's and colleagues' work is to highlight the importance of local banana varieties in different countries.
"We are now conducting an inventory of all the varieties of bananas found on the local market, mainly" In order to convince growers to focus on them, it is also important to protect this variety, as some of these wilder varieties may be even contain genetic traits that are crucial to the survival of the Cavendish. "Recent advances in the mapping of the banana genome have simplified this process a little and are helping researchers to examine the interplay of disease and specific traits and to examine wilder banana strains for multiple genetic traits which may make them wither resistant to pathogens such as Fusarium, by isolating these traits they can be conventionally bred or genetically engineered with commercial banana strains to make them more resilient.
Sanderson Bellamy, on the other hand, believes that we lan In the long run, we need to change the way we farm. "It's been 70 years [since the first fusarium wilt outbreak] and we still have not developed a new variety that could meet all these criteria," she said. "The root cause of the problem is the way we grow bananas."
Solving this problem would mean switching monoculture to smaller farms that are integrated into a variety of crops, she said. These richer agricultural tapestries would be more resistant to pathogens that favor a single crop for their spread and would require fewer pesticides. She believes that the Cavendish catastrophe is a lesson for our increasingly unsustainable agricultural system as a whole. "I think there is a crisis in our food system, and I think the [Cavendish] banana is a good example of how the crisis is manifesting," Sanderson Bellamy said. [How Do Pineapples Grow?]
Changing the way we grow bananas would inevitably mean that we would grow less of them and that they would probably be more expensive, she added. But perhaps this is part of the solution: Consumers need to realize that the ubiquitousness and affordability of this beloved fruit is in reality only the result of a faulty system – and that we may need to adjust to a future where we are looking for more sustainable production pay product. "I do not think the banana price reflects the cost of growing these fruits," said Sanderson Bellamy.
Our next steps will determine whether the famous Cavendish banana can be saved. Although Ella Fitzgerald and Louis Armstrong have crooned "I like bananas and you like banahnahs", we really do not want to break it all off: we like this sweet, yellow fruit way too much.
Originally published on Live Science.