Byebye, Mr Banana?
The succulent, yellow fruits pictured above will be familiar to you as bananas, AKA the world's most popular fruit. To be very specific, they are 'Cavendish' bananas- the variety of banana most commonly sold in the West (it's not too uncommon here in the East, either :P). Unfortunately, that may not be the case in a few years time- the 'Cavendish' is being ravaged by disease and production may drop to the point where it's impossible to satisfy global demand.
The varieties of banana commonly eaten by man are, sadly, quite susceptible to disease. The reason for this is a fact that I myself wasn't aware of til a few days ago: the domestic banana plant is a clone! Genetic engineering is hardly a new science- farmers, through their selective breeding, have been doing it since time immemorial. Our domestic plants and animals have all been changed significantly from their wild counterparts through human efforts. Likewise, the domestic banana has been selected for a trait that makes it's fruit edible to us- namely, a distinct lack of seeds.
I've always wondered why bananas have no seeds and how the heck the tree reproduces. Well, I've found my answer. New banana plants are commonly grown by planting young offshoots of an existing banana plant. The new plant, then, will be a genetic clone of the plant it was propogated from. It is this practice that has allowed the spread of identical-tasting banana plants from Southeast Asia to Africa and the Americas- ensuring that everyone gets to eat the same great-tasting and nutritious fruit.
On the flipside, this also means that there's precious little genetic variation amongst the domestic varieties of banana- hence their remarkable lack of resistance to disease. What affects one banana plant can and will affect all other banana plants of the same variety. History has proved this fact- a 'banana apocalypse' has already happened once. The 'Gros Michel' variety of banana was once the favoured variety sold in the Western world until it was hit by a fungus called Panama disease in the early part of the 20th century. By mid-century, the production had been crippled. After it was clear that there was no way to save the 'Gros Michel', the 'Cavendish'- resistant to Panama Disease- entered the picture as it's replacement.
Unfortunately for us, the wild fungi weren't as genetically-static as the bananas they attacked. In 1992, a new strain of Panama Disease (called Race 4) that could affect 'Cavendish' varieties was discovered. It has since wiped out many plantations in Southeast Asia. It seems certain now that 'Cavendish' will suffer the same fate as 'Gros Michel' before it. All isn't lost, however. This fascinating Popular Science article details efforts by two groups of people to create a new, resistant form of banana: farmers who are trying to create a replacement plant similar enough to 'Cavendish' that consumers won't notice (or rather, mind) the difference and bioengineers who are manipulating the plant's genes to create a hardier, disease-resistant form of 'Cavendish.' Both groups have their work cut out for them; particularly the farmers, as new banana hybrids are hard to grow.
While the loss of the 'Cavendish' will certainly be a loss for banana-growing economies and fruit-lovers everywhere in the developed world, there is an even more pressing issue at hand. Bananas are a staple food in many parts of Africa and even though it is not the 'Cavendish' but other varieties that are commonly grown in many African countries, they too are under threat from the same diseases. The loss of the fruit would be no laughing matter for the millions of people who rely on it as a primary source of nutrition. Finding a solution to the banana's woes is thus a matter of utmost importance.
