A banana plantation

The big banana question

The Cavendish banana is under threat – how can we save it? Or should we look for alternatives?

The banana is one of the world’s most important food crops. In countries where bananas are produced, often by small farmers, over 400 million people rely on them for nourishment and income.

The most common variety is the Cavendish banana, which makes up around 95 per cent of the global supply, but it is under threat from a fungal disease that destroys the roots of the plants. The same disease wiped out another popular banana variety – the Gros Michel – in the 1950s. Unfortunately, because Cavendish bananas are all genetically identical and close to sterile, it’s very difficult to breed new, resistant varieties.

But there are other varieties of banana that are essential to the health of local populations. In Uganda, the East Highland variety is a staple crop and a crucial source of starch, and local scientists are working with Australian researchers at the Queensland University of Technology to improve it. This project – called Banana21 – aims to increase the banana’s levels of vitamin A and iron, often deficient in the Ugandan diet. This biofortification is similar to the way many cereals in the UK have added iron and vitamins.

The researchers are also trying to make bananas more resistant to disease and drought. One variety being trialled is a genetically modified version of a less commonly grown dessert banana called Lady Finger. The modified version has genes that change its response to stress, such as when it is infected by a fungus.

Genetic modification could be a way to develop disease-resistant Cavendish varieties too, as well as making them more nutritious.

Is this a smart approach to solving the banana problem? Or should we be trying to diversify banana farming more widely?

Pros Cons
Possible prevention of total Cavendish wipe-out. Unknown effects of new genes on banana genome.
Providing a means to sustain livelihoods in banana-producing countries. Continues the reliance on the Cavendish variety rather than diversifying banana farming.
Starting small means local populations find solutions for themselves and can contribute what they’ve learned to a potential solution. Consumer reluctance to eating a new variety of banana – and a genetically modified one at that.
  Unknown financial costs of new varieties to small farmers.

Banana stats

  • Nearly 1,000 varieties of bananas in the world.
  • 50 subgroups.
  • Cavendish variety makes up 95% of supply and is the one produced for export markets.
  • Grown in more than 150 countries.
  • 107 million tonnes of fruit produced in 2013.

Lead image:

seaskylab/Shutterstock

References

About this resource

This resource was first published in ‘Plants’ in May 2016.

Topic:
Ecology and environment
Issue:
Plants
Education levels:
16–19, Continuing professional development