Forward Steps in Food Security
By Eve Daniels
There’s no easy answer to the challenge of meeting the nutritional needs of nearly 9 billion people around the world in just a few decades.
One piece of the puzzle, though, is training the next generation of scientists who will have to keep up with evolving demands. That’s the idea behind the MnDRIVE (Minnesota's Discovery, Research and InnoVation Economy) Global Food Ventures Graduate Fellowship program. Now beginning its fourth year, the program is designed to give fellows a better understanding of food systems and policies, so that the fellows can better apply their specific expertise to solve food problems in Minnesota and beyond.
Extending the strawberry season
If you’ve ever tasted a strawberry right from the patch, you know that most store-bought berries are bland in comparison. They also tend to spoil within days of buying them. That’s because strawberries spend most of their lives on a truck, then in a warehouse, then on an airplane, then on store shelves, before they finally make it to our homes.
This issue is especially close to home in Minnesota, where the strawberry growing season lasts just six weeks or less, from June to early July. The rest of the year, most of our berries come from California or Florida. Fortunately, there may be a way to solve this problem in a sustainable way—one that benefits both the environment and the local economy.
Through new cultivars and techniques, MnDRIVE fellow Andrew Petran has been able to extend the season through late October. He’s growing day-neutral strawberries, which differ from the June-bearing types usually grown here, because they are insensitive to day length.
“We’ve been treating them as annuals and using plastic mulch and low tunnels (i.e. miniature greenhouses), versus treating them as perennials and using straw mulch,” explains Petran, who earned his doctoral degree in applied plant sciences in May.
“This approach helps to keep the leaves dry, which reduces disease and protects them from the elements, including wind gusts of up to 80 miles per hour.”
Petran grew the plants at two sites, St. Paul and Morris, on organically certified land using organic fertility practices and drip-tape irrigation, which can reduce water expenditure by up to 75 percent compared to overhead irrigation.
After two years, he’s seen an average rate of more than 20,000 lbs./acre/year, using plastic mulch with low tunnels. That’s a lot more strawberries than the region’s average 5,500 lbs./acre/year.
Moreover, the strawberries are delicious. “They taste like they were already rolled in sugar,” says Petran, adding that each variety has its own unique flavor.
It seems Minnesotans are happy to pay extra for them, too. “We donated a lot of fruit to University of Minnesota students to sell at the farmer’s market,” says Petran. “They sold them all for $5 a pint, which equates to more than triple what retailers get.”
Resisting rust fungi
Growing up in Yingxian, a small village in northern China, Feng Li saw the effects of plant disease first hand. “My aunt was a farmer, and when she would have a bad year in the field, I wanted to do something to help,” says Li.
Today, as a graduate student in plant pathology, Li is getting a chance to help farmers like her aunt, across the globe. Following in the footsteps of Norman Borlaug and notable researchers like him, she’s advancing our knowledge of stem rust, one of the world’s most devastating plant diseases.
As part of her MnDRIVE project, Li is investigating the factors of stem rust resistance in Brachypodium distachyon, a grass species from southern Europe, northern Africa and southwestern Asia. This grass is related to cereal grain species including wheat, barley, oats and maize.
Her findings will not only increase our knowledge of non-host resistance against rust fungi, but also help to establish Brachypodium as a model for studying cereal disease resistance.
“I would like to have a better understanding of the plant microbe interactions so that we can develop novel strategies for plant protection,” she says. “Advancing our knowledge in this field can make translational research and innovations possible.”
Fighting foodborne illness
Listeria is a worrisome word for the food industry. The infection, caused by eating food with the bacterium Listeria monocytogenes, is responsible for 1,600 cases of foodborne illness each year in the United States. Of those cases, about 255 people die
So, finding ways to control the infection is truly a matter of life and death. It’s also a financial matter, as the impacts of listeria cost the food industry nearly $3 billion annually, according to a recent USDA analysis.
To tackle this critical issue, MnDRIVE fellow Zach Metz is combining his undergraduate training in chemical engineering with his graduate work in food science.
“I’m using genome-scale metabolic models, which are created by downloading publicly available genome strains of Listeria monocytogenes, and then I upload those genomes to an online database to create a base model,” he explains.
“I take those models and run computer simulations, and try to predict what compounds listeria can use as a source of carbon, nitrogen, phosphorus and sulfur.” From there, he tries to grow listeria on those compounds in the lab, and to make those results agree with the model as much as possible.
“After doing the experiments in the lab and adjusting the models, I got them so that they agree about 85 percent with experimental results, which is pretty standard for a published version of one of these models,” says Metz.
The ultimate goal is to provide a more accurate predictive tool to aid in the prevention and treatment of listeria.
Protecting animal feed
Since its appearance in the U.S. in 2013, porcine epidemic diarrhea (PEDv) has quickly spread within the swine industry. The virus has killed millions of pigs and has boosted pork prices to all-time highs.
Speculation continues about the origins of the virus, but experts believe that animal feed is one way it can enter pig barns. That’s where Mickie Trudeau’s research comes into play.
“I focus on how long the virus survives in different feeds and what can be done to limit its survival and make the feed safe for the farms,” she explains. “This includes heating the feed or using different feed additives, such as organic acids, to reduce virus survival.”
Early research trials show that plant-based meal may be an ingredient to watch more closely. “Originally, animal byproducts were blamed because they come from pigs, but we’re seeing soybean meal and even corn have high survival rates, so we’re trying to figure out what’s causing that,” says Trudeau.
After defending her master’s thesis later this summer, Trudeau plans to stay at the University of Minnesota to pursue her PhD in swine nutrition. Over the past year, she says the MnDRIVE fellowship has not only paid her salary, but has also given her a more balanced perspective on food systems in general.
“As fellows, we’ve all taken classes in food production, food security and other relevant topics, so instead of being really good at just one thing, we have a broader sense of how our project fits into everything.”