Grad student develops a family tree for corn varieties in North America

By Meghan Chua

Corn at a UW-Madison crop nursery
As of May 2019, the genetic information for 460 varieties of corn alone are available to the public since their plant variety protections expired. By 2028, there will be 750 more corn varieties available.

When plant breeders develop a new line of crops, plant variety protections allow that breeder to keep the rights to it. Plant varieties, many of which are created by private seed companies, are protected this way for 20 years before their genetic information becomes publicly available.

As of May 2019, the genetic information for 460 varieties of corn alone are available this way. By 2028, there will be 750 more corn varieties available. All of this adds up to a lot of data of different corn lines that public and private researchers can access.

Mike White
Mike White

“The material is quite elite still,” said graduate student Mike White. “Even though it’s 20 years old it is a large source of elite germplasm for companies to use and improve on.”

To help researchers better understand the relationships between these varieties of corn, White and his colleagues developed molecular markers and genomic tools that give breeders a glimpse into the genetic features of each line.

Using statistics and bioinformatics, White organized unrelated corn varieties into a vast family tree for maize lines in North America. Previous studies have clustered maize varieties together, but a greater understanding of these crop varieties will help public researchers and other breeding companies better use the information.

“Just like how 23andMe shows your ancestry, it’s the same principle with corn,” White said. “We’re looking at what lines are related, how they’ve been utilized over the history of breeding, and ways that we could make this information less complex and allow smaller-share or public universities to use the material present without doing a lot of this work themselves.”

White’s paper on the subject will be published in the journal Crop Science.

White has long been part of the plant breeding field. Growing up in Janesville, Wisconsin, he started working at Syngenta as a summer job when he was 11 years old. He continued working summers there through his undergraduate study at the University of Minnesota.

“I was always intrigued by genetics and how things can improve over time with selection, and using molecular markers and new bioinformatic techniques to improve crops that we use in the U.S.,” he said.

He came to UW–Madison to pursue a PhD in the Plant Breeding and Plant Genetics program, studying with Natalia de Leon and Shawn Kaeppler. White said he was drawn by the multidisciplinary connections among the department, and the opportunity to pursue his research interests.

During graduate school, he has found the connections with people and alumni from the department invaluable.

“There’s a lot of people that our lab and our program have sent out to bigger companies and it’s great to stay connected with them, see what industry is doing, and really to help tailor your research to do what you [want],” he said. “I’ve been interested in private industry, so I’ve had the flexibility to tailor my research and network more with people that are in private industry.”

This winter, White will receive his PhD and move to France to work for the private seed company Euralis as a corn breeder developing future generations of maize.

This work was supported by the USDA National Institute of Food and Agriculture Hatch Projects WIS01923 and WIS02020. White’s graduate work was also supported by the Dave and Sharron Mies Fellowship.