(host) A buttery ear of corn at a barbecue, a big bucket of popcorn at the movies, or a blue corn tortilla. Corn is everywhere. But as our planet gets hotter, corn is facing pressure to thrive and survive. So to keep tamales and succotash and elote on our plates, scientists and farmers need to find new strains of corn that can adapt to warmer temperatures. And one researcher is doing that with an unexpected tool-- a corn a photobooth.

[photos snapping]

(Describer) Corn grows in photos.

(speaker) When I look at different types of corn, I'm trying to understand the natural responses to pick out the corn plants that grow the best under these future climate conditions.

(speaker) The Mechicas, the Incas, the Aztecs, the Mayans-- they grew their civilization because of the corn. It comes from our ancestors.

(host) This is Hungry Planet. Let's dig in.

(Describer) PBS Terra. An animated whale swims.

Corn is a staple food for people around the world, from the plains of Nebraska to the Pampas of Argentina. And globally, corn accounts for around 5% of everyone's calorie intake. And it's more than twice that in places like Latin America. But the climate crisis has the potential to reduce global corn yields by around 7% for every centigrade rise in temperature. So, if corn is going to keep feeding the world-- and it does feed the world, as well as feed our livestock and power our cars-- we need to find a way to keep it thriving. Thankfully, corn is resilient, and so are the people who work with it. Before we get into whether and how corn might handle the increased heat and decreased water of the future, let's dig into corn-based cuisine with Deysi Serrano. Deysi is the owner of Milpa Grille in Boyle Heights, LA, and she uses corn as the backbone of healthy food for her community.

(Deysi) So Milpa is the way that the three sisters grow, or where it grows, its foundation. But it was really back in Mesoamerican time. So where the three sisters came alive.

(Niba) The plants have the three sisters-- corn, beans, and squash-- they all work together. The corn provides support for the beans, the beans add important nitrogen to the soil, and the squash leaves shade out any potential weeds.

(Deysi) It was this beautiful system that came to be back in the day we have Mechicas, Incas, and also made it possible for their community to grow. How did you end up getting this restaurant? During COVID, I felt that we needed to empower the community when no one was selling and doing pop ups. And then it came into this three-concept kitchen where you're gonna see coffee, you're gonna see another brand who does burritos, and then you have Milpa. I had a gut feeling that this is what I needed to do. Boyle Heights has a lot of culture, and we know where we come from. And we decided that we deserve a nice space that you can come in and eat. You have your first generation Mexican-American children. And so the children usually are the first ones to come to the restaurant, because, you know, we're a bit more open-minded. Then you have their parents, who are usually immigrants. And then we're low income. So you have apartments where you have two, three families living in there. And so, it's tough. You know, and I think we wanted to keep a space where it's a safe space, and also make sure it's available for them. Not just that; it's the same concept you've always known, which is the corn, squash, and beans. So this is nothing new. We're plating it differently. But there's nothing else.

(Niba) Corn is important to communities around the world. From 2021 to '22, the world consumed nearly 50 billion bushels of corn. That's over 700,000 Olympic swimming pools full of corn. And part of this is because corn is an incredibly versatile crop. Domesticated in Mexico almost 9,000 years ago from an ancestral plant called teosinte, everything from the husk to the kernels can and is used. Corn is also extremely adaptable. Its genes vary a lot from plant to plant and variety to variety, which allows it to morph and grow and adapt and bloom in a huge range of environments. So for chefs like Deysi to continue providing it to their communities, corn needs to keep growing in spite of this rapidly changing climate. And that's where scientists like Dr. Katie Murphy come in. When I look at different types of corn, I'm trying to understand the natural responses to pick out the corn plants that grow the best under these future climate conditions. That way, we hope to be able to grow more food but using less land and less resources. First of all, I just love corn. Who doesn't like to eat corn on the cob, right? What am I? But also, corn is really really important. It's one of the largest calorie providers in the world, right? The world grows a lot of corn, and especially the United States. Climate change is a major issue. We know that we have more extreme weather conditions and also hotter weather in general. We as as plant scientists are trying to equip farmers to grow more food using less land and less resources. Every time a farmer plants seed, they plant their seed out in the field and the plants grow, some of those plants will die. Some plants might survive, but they might have lower yields. And that's because of pressures from the environment, temperature, water. So, what we need to do is to use the same amount of land, but grow more food.

(Niba) Katie's work looks at how individual genes in the DNA of corn affect the traits, or phenotypes, of the corn plant. Like how tall it is, how it deals with drought, how many heads of corn are made, and more. The idea is to find genes that allow corn to thrive in the future climate and environment. But accurately planting, watering, and measuring hundreds of plants is time consuming and labor intensive. So Katie's work uses a different strategy.

(Katie) What we do is we have a high throughput phenotyping facility. So this lovely plant actually lives on this carriage here. You can see it's got a barcode a number, and on the back is actually an RFID chip that we use to track this carriage. The plants wake up each morning. We have the lights slowly turn on. We have 1,140 plants that live on their little carriages here inside of our controlled-growth facility. We control the temperature, the humidity, the lighting. We have a camera that I can check from home to see how the plants are doing every morning while I have my coffee. It rides around on a conveyor belt that is really a selfie station. Right, the plants ride around every single day and they get a selfie taken. We can then analyze those images so that I don't have to go in and use a ruler to measure the plants. We can use computer science to make measurements. When once we know those measurements, we can understand how this plant has responded to different environments compared to other plants, and connect that to the plant genome, the genotype, in order to help farmers for breeding and engineering future climate-resilient crops. We can look back at a diversity of corn seed that's available for researchers to use to understand how different genotypes naturally respond to these conditions. And then we hope to prevent crop losses through traditional breeding and plant engineering from the knowledge we gain from our research.

(Niba) Once they can identify which genes are associated with resisting drought and heat, Katie and her team can engineer corn crops that can survive in the field. And that ensures that Deysi and others like her can continue making food for their communities for generations to come.

(Describer) A server hands Niba and Deysi food.

Sweet. Thank you. Nopales! I've been wanting to try these for so long. Yeah, they're delish, especially when they're grilled. You're going to have a base of grilled corn, and then you're going to have black beans on the side. And right in the middle of that, you're going to have your grilled veggies. So that's your three sisters all in one bowl. And then that's your soup there, the crema de elote. And so it's made out of some chiles poblanos and sour cream topped off with some grilled corn. We get a lot of customers saying, "Oh my God, this feels like my grandmother's soup." And it's so nice. It's not nothing crazy. It's nothing new. The crema de elote has been around, but it's nice to hear people just say, "Hey, this is what my grandma used to make."

(Niba) Like food really is the foundation of community, whether that's a civilization, like thousands of years ago, or even now here. You're nurturing your community, your civilization, whatever it is, and you're making it grow and you're making an impact through food, which is-- I don't know-- it's crazy to believe that you can do that.

(Niba) Feeding the future is going to take entrepreneurs like Deysi and scientists like Katie working in parallel to make sure corn is both available and delicious.

(Katie) I think what really gives me hope is we have so many wonderful young people who are working to understand plant science, and are really dedicating their lives and their careers to making better crops. And that for me is really exciting. We can do so much more than we could last year, than we could ten years ago. It's crazy. So I'm so hopeful for the future because there's wonderful people and wonderful technologies that I think are going to allow us to make a more sustainable food system.

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