Britain’s recent ‘Sausage Wars’ remind me of Boris Johnson’s previous pork pies about straight bananas — back in his journalism days — and they coincide with a serious threat to our favourite fruit.
anama disease, a strain of fusarium, could cripple international trade in bananas.
If a banana is a fruit, where are the seeds? In a commercial banana there aren’t any because the plant that produces it is sterile. Wild bananas have seeds and by all accounts are not very nice to eat.
Naturally occurring mutations of the banana plant occasionally produce a triploid variant which has three sets of chromosomes and cannot reproduce sexually.
For thousands of years these variants have been grown for food, as their seedless fruits are more palatable.
They are multiplied by cuttings, each genetically identical to its parent, with the same strengths, such as high yield, tasty fruit and drought tolerance.
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Unfortunately, they also share weaknesses, and fungi are superbly equipped to exploit these. Fungi breed at phenomenal rates and are continuously mutating, and when they produce a variant with a big advantage in a particular environment, they can rapidly multiply — literally mushrooming.
Think of the fungus as a thief and imagine that the individual plants in a crop are the houses in a city.
If the fungus has to pick a different lock to get into each house, it will not get into very many each night; this is the situation a fungus finds in a genetically diverse crop.
But if the fungus finds that every lock is identical, and a single key opens every door, then the city is there for the taking.
With its identical clones, the banana crop now finds itself in this terrible situation, and not for the first time; 99pc of internationally traded bananas are of a single variety, the Cavendish, which is succumbing to a strain of Panama disease.
The disease is soil-borne, persisting in the ground for decades, and fungicides now have little effect on it.
In the 1950s the then dominant banana variety, Gros Michel, was devastated by the disease, and Cavendish, which was resistant, was hailed as the saviour.
Cavendish has done pretty well to last nearly seven decades, probably with the help of more fungicides than we care to think about, but its days are numbered and there is no obvious replacement variety.
Despite the earlier experience of losing a single dominant variety, and the inevitability of the eventual breakdown of Cavendish, there appears to have been very little ongoing work to develop replacement varieties.
Breeding triploid plants is not impossible but it is tricky and very slow and is not likely to replace Cavendish in time to save the banana industry.
Genetic modification offers speedier results, and the most promising work involves the insertion of genes from nematodes — microscopic parasites — into the banana plant to protect it from Panama disease.
Genetic modification covers a wide range of technologies, from transgenic work producing so-called Frankenfoods to gene-editing techniques that claim to be little more than enhanced natural selection.
Potatoes are another important crop that reproduces asexually, and gene editing is proposed to speed up the development of new varieties.
We already make distinctions in practice between humans and livestock when it comes to consuming GM products: GM crops are not allowed to be grown in the EU, but our farmers compete with them in animal feed markets.
We face some tough choices. Are we comfortable with GM tech? Or do we accept that bananas may become scarce and expensive?
Genetically modified foods are prohibited in the EU, so the British could have the last laugh as they continue eating bendy bananas while we have none.
It may be time for a more detailed look at our attitudes to GM foods.
And it is also time to look at the kind of cropping practices that have led to this banana crisis.
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Andrew Bergin is a tillage farmer based near Athy, Co Kildare