The seed guardians in the Andes trying to save the potato

From potatoes to quinoa, many of our favourite foods are at risk from threats like climate change and disease. The “seed guardians” of Peru’s Potato Park are hoping to change that. The potatoes that grow in the Andes of South America are far more than a starchy staple of the local diet. They are a rich part of the culture. “There’s one really wonderfully beautiful potato, it looks almost like a rose. And the name of that one is ‘the-one-that-makes-the-daughter-in-law-cry’,” says Tammy Stenner, executive assistant at Asociación Andes, a non-profit organisation in Cusco, Peru, that works to protect biodiversity and indigenous rights in the region. “A potential mother-in-law would ask the young woman who wants to marry her son to peel this potato, but she has to peel it with care, so not wasting the flesh, not ruining the shape.” It is just one of more than 1,300 varieties of potato to be found growing in the mountains of the Andes, somewhere between 3,200m and 5,000m (10,500ft-16,500ft) above sea level. These are not the smooth-skinned russets or pale Maris Pipers that can be found on supermarket shelves in Europe and the US. Instead, they come in shades of purple, pink, red, and black, as well as white and yellow. Some have so many lumps and bumps that peeling them is enough to bring tears to the eyes. Others require special methods of preparation. There are some that have to be freeze-dried (using one of two different methods for doing so), some that should only be cooked whole, and those that can be peeled and cut up for cooking. Individual varieties often have wonderfully descriptive names that describe their shape: one name translates to “puma’s paw”, another to “llama’s nose”. Then there are the potatoes named according to the role they play in the field, like the wild relatives of the cultivated potatoes known as the “grandfathers”, or the role they play in local customs. But now these beguiling vegetables have a new and vital role to play – helping to ensure potato crops can adapt to the challenges of climate change. There are more than 1,300 varieties of potato to be found growing in the mountains of the Andes (Credit: Andes) Potato Park , located near the Peruvian town of Pisac, was founded by six indigenous communities in 2002 to preserve the genetic diversity of potatoes grown in the region, as well as the cultural heritage of the people that grow them. Other native Andean crops grow here, too, from maize to quinoa. The agricultural methods used in the park have been developed over thousands of years, and resilience to extreme weather, such as that caused by El Niño, is built in . Farmers also vary planting locations within the almost 10,000-hectare (38 sq miles) reserve, and harvest at multiple times across the year. As well as preserving many varieties of potatoes that might otherwise be lost – along with the agricultural knowledge and traditions involved in growing potatoes at high altitude – farmers are testing which of the existing varieties can best adapt to the kind of extreme conditions that are expected to become more common as the global climate changes .   “Potatoes were domesticated in the Andes about 8,000 years ago, so there’s a lot of history and a lot of knowledge about how to grow potatoes,” says Stenner, who helps to support the park through her work with Asociación Andes. “But it’s always been based on diversity.” The work taking place at Potato Park is part of a much larger effort to find ways of preserving and adapting valuable food plants around the world as they face threats from climate change, habitat destruction, pollution and plain old neglect. Seed banks are often seen as the ultimate protectors of crop diversity to help ensure food security. The Svalbard Global Seed Vault , which holds backup versions of seeds from all over the world, including some deposited by representatives of the Potato Park in 2017, is nicknamed “the doomsday vault”. Such repositories may be a vital safeguard against losing valued crops, but they’re just one part of a global network that includes peasant farmers and even backyard growers who are protecting the genetic diversity of our food. These small-scale growers keeping alive thousands of rare and unusual crop varieties do so through careful cultivation and seed-saving in gardens and on farms. In fact, research suggests that the majority of global seed diversity is held by the world’s 2.5 billion smallholders rather than in gene banks . Many crops cultivated by these seed guardians are far more interesting than anything you could buy in a supermarket – from purple potatoes to cucumbers that look just like lemons and rainbow corn whose kernels resemble tiny jewels on the cob . Growing a diverse range of varieties of a particular crop used to be a widespread practice in agriculture. But when scientists began breeding “improved” varieties of staple crops such as corn and wheat, many farmers replaced locally adapted varieties – known as landraces – with modern versions . “There have been profound transformations in agriculture, and there has been loss of crop diversity, that’s incontrovertible,” says Helen Anne Curry, a professor in the history of technology at Georgia Tech in Georgia, US. For several decades, seed banks, also known as gene banks, where seeds and other plant materials are kept in long-term storage, have been one answer to this problem . But in situ conservation – where crops are preserved through cultivation in the field – is another vital piece of the puzzle. “The seed banks are not a final destination, but a holding place as part of a larger operation,” says Curry. By conserving crops through cultivation, they are constantly given opportunities to adapt to real world conditions – and by selecting for crops that thrive in certain conditions, or cross-breeding varieties that have desirable traits, farmers are given the chance to influence how they change over time, too. In fact, you don’t need to be a farmer to save seeds and steward a diverse range of crops for the future. Seed Savers Exchange is a non-profit organisation based in Iowa, US, dedicated to the preservation of heirloom seeds. The organisation uses a combination of ex situ conservation (long-term storage of seeds in their gene bank) and in situ conservation (sharing their seeds with gardeners and farmers to grow). All of their seeds are open-pollinated, which means that growers can save their own seed year after year. The potato park in Pisac, Peru, was founded by six indigenous communities in 2002 (Credit: Andes) As well as holding information on the cultural heritage of their heirloom seeds – gathered by specialist seed historians – Seed Savers Exchange is working with a network of 700 gardeners across the US to help it learn which varieties might best adapt to different environments. Those gardeners grow seeds that the organisation would like more information on, then report back on aspects like germination rate, growth habit, and how the plants are doing in their climate. “These are people that are all across the country, so it allows us to be able to start to see what sort of environments some of these crops are thriving in,” says Mike Bollinger, executive director of Seed Savers Exchange. Seed saving also opens up possibilities to create new varieties that are better adapted to local conditions, or which have other selling points. Take the German pink tomato, one of the heirloom varieties brought to the US in 1883 by the grandfather of Seed Savers Exchange co-founder Diane Ott Whealy. If you grow several plants of that one variety in your garden, there’ll be slight variations between all of them. One might produce its tomatoes slightly earlier, whereas another might make bigger or tastier fruits. By choosing which plants to save seed from, you can select for those plants with the traits that you want to preserve. “It continues to be that same German pink tomato, but you’re adapting for the environment that you’re in, the traits that you like,” says Bollinger. You can also go one step further, allowing different varieties of a plant with traits you’d like to combine to cross-pollinate, then saving seeds from plants that have those desirable traits. Repeating this process year after year is how Oklahoma farmer Carl Barnes cultivated the rainbow-coloured glass gem corn that became an internet sensation in 2012 . This process of adaptation is also key when it comes to finding crops that will be resilient in the face of extreme weather and climate change. Instead of relying on scientists to create new varieties in the laboratory using seeds pulled from cold storage, cultivation offers constant opportunities for existing varieties to adapt to whatever is thrown at them. “In situ conservation is really important because then the plants are continually adapting to the real conditions, not laboratory conditions,” says Stenner. In the Potato Park, research by farmers has shown that the ideal conditions for different potato varieties are moving up the mountain to cooler altitudes as average temperatures rise . But they can only do this for so long. “Because they’re so high already, they’re running out of space to keep doing that,” says Stenner. As one of the community elders said: “You can’t grow potatoes in the sky”. So, the farmers are instead nudging the potatoes towards re-adapting to lower altitudes. “There’s so much built into a lot of these open-pollinated varieties already, it’s a matter of being able to start growing these out and using the inherent genetics in them,” says Bollinger. “You can navigate through that with the intelligence that is already built in… as opposed to trying to use technology to create something that doesn’t exist.” — Join one million Future fans by liking us on Facebook , or follow us on Twitter or Instagram . If you liked this story, sign up for the weekly bbc.com features newsletter , called “The Essential List” – a handpicked selection of stories from BBC Future , Culture , Worklife , Travel and Reel delivered to your inbox every Friday. ;