Same spuds different story: Britain's potatoes in a changing world
Potatoes are an iconic part of the British national identity and cuisine. Fish and chips is arguably the most famous British food there is, and almost every traditional British meal – pie and mash, roast dinners, shepherd’s pie – comes with a generous serving of potatoes. But the truth is that, behind the scenes, it takes constant work to ensure the potato remains a sustainable crop.
Same spuds different story: Britain's potatoes in a changing world
Potatoes are an iconic part of the British national identity and cuisine. Fish and chips is arguably the most famous British food there is, and almost every traditional British meal – pie and mash, roast dinners, shepherd’s pie – comes with a generous serving of potatoes. But the truth is that, behind the scenes, it takes constant work to ensure the potato remains a sustainable crop.
To the casual shopper, white potatoes might appear identical. Many consumers would struggle to identify different types just by looking at them. But with potatoes, it really is what’s on the inside that counts – and this goes far deeper than waxy versus starchy. Disease and pest resistance in particular are crucial to ensuring a spud’s success. The potato’s humble appearance masks just how much sweat and science it takes to keep this beloved crop on our plates.
Problems have plagued the European potato industry for as long as it’s been around. Potato diseases are many and varied, attacking potatoes at all stages of their life cycle. They are vulnerable to viral infection from aphids attacking their leaves, potato cyst nematodes are spreading through British soil and, of course, late blight attacks fully grown potatoes. These problems have always existed, but climate change is making things worse. Wetter summers make potatoes more susceptible to late blight. Warmer temperatures mean even seed potatoes from Scotland are increasingly susceptible to viruses transmitted through aphids. While the British appetite for potatoes is going nowhere, the challenges farmers face are multiplying rapidly.
One way scientists try to develop disease resistance in potatoes is through cross-breeding potatoes to develop new varieties. Dr. Max Coleman, Science Communicator for the Royal Botanic Garden Edinburgh, explained how preserving wild relatives of potatoes is critical to developing and improving potato varieties. The genetic diversity found in wild potatoes is a potential source of disease-resistant genes. As a result, gene banks like those found at the Commonwealth Potato Collection and potato species conservation are both hugely important to the British potato industry. For example, the Edinburgh potato was grown at the Royal Botanic Garden Edinburgh in the 19th century. A cross between the modern, domesticated potato and a wild Mexican potato, it inherited genetic resistance to late blight from its wild, Mexican parent. Maris Piper, now one of the most popular varieties, was introduced in 1966, using genes from wild Andean potatoes. Like many things about the potato, it feels eternal – but it’s not.
Professor Ingo Hein, Head of Potato Genetics at the James Hutton Institute, and a Professor of Crop Genetics at the University of Dundee, explained that Maris Piper was specifically developed to resist Globodera rostochiensis, a type of potato cyst nematode (PCN). Once this tiny potato-destroying worm spreads to a field, it’s extremely hard to eradicate. PCN is one of the biggest issues facing British potato farmers, costing the industry tens of millions.
‘Maris Piper was the first cultivar released that has a resistance called H1, and the resistance actually comes from the Commonwealth Potato Collection we have at the Hutton now. It controls one part of the PCN problem.’
The H1 gene was phenomenal at giving Maris Piper resistance to G. rostochiensis. However, as Professor Hein noted, H1 can only do so much. G. rostochiensis is just one type of PCN and Maris Piper potatoes are still extremely susceptible to another type of PCN called G. pallida. The enduring popularity of Maris Piper has contributed to the spread of G. pallida around the UK.
And that’s not the only problem with older varieties. Older varieties like Maris Piper and King Edwards that were once resistant to late blight lose resistance as time goes on since the water mold that causes late blight, Phytophthora infestans, evolves incredibly quickly. Hein told me ‘It’s very similar to COVID. You have a vaccine that's effective against one version, but then the virus changes and your vaccine becomes ineffective. It's exactly the same with late blight.’
‘[Maris Piper] is an older cultivar, it's over 60 years old.’ explained Hein. ‘And of course, the way it's maintained, as tubers, a cultivar will not change. But the environment has changed…Therefore now it is actually really ill equipped, I would completely agree. And it's not just Maris Piper, but it's King Edward. You’ve probably heard of King Edward potatoes. Still really, really popular, they were released in 1902: nothing in terms of resistance.’
Unusually wet weather due to climate change not only makes late blight more likely, increasing the amount of pesticide used, it means that pesticides are washed off the plants, so farmers need to spray even more. Using newer, blight-resistant varieties helps reduce the amount of pesticides farmers need to use. Businesses like Greenvale have been working for decades to bring new varieties to the market with increased resistance, such as the Karelia potato variety, which has resistance to G. rostochiensis and G. pallida.
‘I think the carbon footprint for Maris Piper, Desirée, King Edwards and so on would be really, really poor compared to something more modern, where you maybe don't need as much fertiliser, you don't need as many chemicals to protect it.’ Hein told me.
The potato industry’s problems are complex and clearly require a range of solutions and innovations. But, new varieties are critical for potato farmers. They can help reduce pesticide use, improve yields and even taste better. However, developing new varieties of potatoes takes decades. And, all that time, conditions for farmers are still constantly evolving and changing. In order to succeed, supermarkets need to be open to buying new varieties and customers need to be willing to try different potatoes.
As Professor Hein summarised, ‘Old varieties were good at the time, but they are ill adapted to the current climate and the current challenges that we have at large. We need varieties that are better attuned to the challenges, including the pathogens, which hopefully require less input with fertilisers and so on. And I think the only way we can do this is by bringing in new varieties.’
The Maris Piper, it’s true, has stayed dutifully the same – but the world it’s grown in has not.
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