Back in the mid-1800s, humanity encountered one of the most infamous and deadly  food catastrophes of all time: the Great Potato Famine.

At a time when potatoes provided  many communities with most or all of their daily nutrients, a  devastating disease tore across farmlands, destroying crops and leaving millions to starve. Maybe you learned about all  of this in history class.

But potato problems aren’t  just a thing of the past. With pesticide resistance and  global temperatures on the rise, potatoes may be in trouble again. So here’s what scientists and farmers are doing right now to prevent the next Great Potato Famine. [♪INTRO] Potatoes were first domesticated  more than 7,000 years ago by people living near the Andes  Mountains in South America.

Because the Andes have cold  peaks and warm valleys, a lot of different kinds of potatoes  could grow in their native Peru. And I mean a lot. There’s an  International Potato Center in Peru that holds almost 5,000 varieties.

So potatoes are a super diverse  crop. But only in the Andes. When potatoes were picked  up by European colonizers and spread around the world,  they clearly didn’t replicate the huge diversity that existed in South America.

It became common practice to fill farmlands with lots of nearly identical potato plants. In fact, there are only around  seven species of cultivated potatoes and only one of them  is distributed around the world. Nevertheless, potatoes persisted!

They ended up thriving in  Ireland, where they formed an essential part of daily diets,  especially among people who were kept from cultivating  their own food on large farms. See, potato plants are pretty easy to grow, even on small, less fertile plots of land. On top of that, potatoes are super nutritious.

They have all sorts of  vitamins, minerals, and fiber, and are generally considered a  nearly perfect food for us humans. Plus, there’s so much you can do with them! Boil ‘em, mash ‘em, stick ‘em in a stew… So, many Irish people pretty much lived off potatoes in the late 1700s and early 1800s.

Unfortunately, as potatoes were  shipped all over the world, they brought along little hitchhikers. The 1800s saw the rise of a fungus-like pathogen known as potato blight. The signs of a blighted  potato tend to start off small with little green lesions on the plant’s leaves.

In the right conditions, these  can give rise to white mildew and rotting blotches that can destroy the leaves and infect the underground  tubers, AKA the potato itself. If it isn’t treated properly,  potato blight can wipe out an entire field of potatoes in a matter of days. Back in the potato’s homeland in South America, farmers didn’t have to worry  much about blight because their crops contained many  different types of potatoes.

The disease might infect some of the  crops, but it couldn’t jump easily between potato types, so any  outbreaks were pretty well contained. But the monocultures on other  continents meant that if potato blight got a foothold, it could  quickly devastate the food supply. During the 1840s, lots of  countries around the world were having blight problems, but  none had it as bad as Ireland.

At the time, there weren’t any established techniques for combating the disease. And a series of unhelpful  policies adopted by their neighbors in the UK only made  things worse for the Irish. Like taking ownership of most  Irish farmland and exporting their goods so Irish farmers struggled to  grow food for their own families.

During a time when the Irish people really only had enough land to farm potatoes, they suffered enormous losses to their crops from potato blight. This led to the infamous Irish Potato Famine. Around one million people starved to death, and another million or so  left the country to escape.

The famine had a devastating and lasting impact on the population and culture of Ireland. It wasn’t until later that century that scientists finally found a solution to  potato blight: a cocktail of lime and copper sulfate called the Bordeaux mixture, which killed the pathogen and  stopped infections in their tracks. It was the world’s first fungicide.

Since then, pesticides for other potato pathogens have been developed, and together, they’ve protected the crop for more than a century. It seemed like a happy ending for the potato. Today, more than 300 million tons  of potatoes are produced each year, which go on to become pierogies,  samosas, french fries, and so much more, providing  food for billions of people.

They’ve been farmed everywhere from  Antarctica to literal outer space! Potatoes are now one of the world’s most important food crops, coming in behind only rice and wheat. But you saw the title of this video, so you know that’s only the  first chapter of the story.

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To this day, blight remains  a huge pain in the potatoes. Several blight outbreaks have  happened over the last few decades, and every year, many tons of  potatoes are lost to infection. See, fungicides aren’t perfect.

Potato  blight is impressively adaptable, and it’s constantly developing  resistance to our chemical treatment, rendering it less and less effective over time. And blight isn’t the only potato pest out there. Farmers have to watch out for insects like the infamous Colorado potato beetle.

These colorful little critters  can be found across North America, Europe, and Asia, where they’re  known to spend their entire life cycle chomping happily on  potato leaves, stems, and tubers. It’s a feast for the beetles and  a death sentence for the plants. If they’re not controlled, these bugs can wipe out entire fields of potatoes.

Like potato blight, potato beetles are also really good at developing  resistance to pesticides. And if that fails, they’re  migratory, so they can just fly off to greener potato pastures. So  they’re really hard to eliminate.

On top of that, pesticide resistance  isn’t the only troubling change. The Earth’s climate is changing,  too, leading to warmer global temperatures and more droughts,  storms, and other extreme weather. Scientists estimate that pests like potato beetles are going to thrive under those warmer conditions, and expand their home ranges into new areas.

And increasing rainfall in some  regions will create moist conditions that encourage the growth of  infectious microbes like potato blight. So the changing climate will  almost certainly help pests. But it may also hinder potato plants.

When temperatures get too high,  the most common potato plants grow slower, develop physical deformities,  and end up with tissue damage. On the other hand, cold snaps  can generate ice that damages potato leaves and stems, basically  causing potato frostbite. And if conditions become too dry,  potato plants get dehydrated, which disrupts their growth and can cause a type of tissue decay called blackheart.

We’re already seeing the effects  of climate change on potatoes. Germany lost 30% of their potato  crops after a 2018 summer drought. Using predictive climate models,  researchers have estimated that without preventative  action, global potato crops could decline as much as  25% in the coming decades.

In certain regions, models  predict nearly 100% loss. So unless we do something, a future Potato Famine is not out of the question. Fortunately, we’re doing something.  Lots of somethings, actually.

Farmers and food scientists around the world have been developing solutions. Some of these solutions come  from the potatoes themselves. Despite all the dangers,  potato plants aren’t helpless.

They’re hardy organisms capable of  surviving various tough conditions. And some of them are better at it than others. Which means the occasional  extra-tough potato plant can be cultivated into a whole  new strain of super-potatoes.

Various breeding programs  have produced potatoes that are extra good at dealing  with droughts and heat waves, while others have developed  potatoes that mature early, providing extra flexibility to planting schedules. For example, in India, kufri  pukhraj potatoes mature early and do well in droughts, while kufri sindhuri potatoes are particularly resistant to high heat. Of course, there are limitations to all of this.

Most potato breeds are one-trick taters. It’s tough to cultivate plants  with multiple special qualities. For example, your potatoes  could be drought-resistant or heat-resistant, but they often can’t be both.

Unless we give the potatoes a  little boost with genetic editing. In a 2024 study, scientists deleted  the gene that codes for a specific protein in potatoes, allowing them  to become more resilient in the face of drought and more resistant to  their dreaded nemesis, potato blight. But pesticides and gene therapy aren’t the only ways to keep potato blight away.

Studies have shown that just covering  a potato field with straw mulch can reduce the impacts of both  potato blight and potato beetles. So farmers have a lot of tools in their belt. And that’s before we even ask  our microbe friends for help.

I know I’ve talked a lot about  microbes causing terrible disease, but not all microbes are anti-potato. Research has found that certain  root bacteria can promote healthy plant growth, and when  carefully applied to crops, they can help potatoes thrive  even in harsh conditions. The future is full of dangers for potatoes, but a combination of specialized  farming techniques, targeted breeding, and genetic engineering  might just keep them safe.

The Great Potato Famine of the past was devastating because people  weren’t prepared for it. But we have all the knowledge and  the tools to prevent the next one. So let’s hope scientists are successful  in their quest to save the spuds.

Because I would really miss potato chips, and aloo gobi, and tater tots, and potato wedges, and potato salad, and crinkle-cut fries– Should I keep going? [♪OUTRO]