Studying genetics of potatoes

When most people think of potatoes, the word research does not usually follow. But with their Mr. Potato head mascot watching over the lab, the University of Nevada Reno’s plant biology tag team, Dylan Kosma and Patricia Santos, are searching for ways to reduce potato crop losses during storage.

The University’s Kosma-Santos lab, in the College of Agriculture, Biotechnology and Natural Resources, was recently awarded a $1.37 grant by the National Science Foundation to investigate the molecular-genetics and biochemistry that underlies potato crop losses during tuber storage. As the number one vegetable crop in the United States and a top five crop for the state of Nevada, potato crop losses can be economically devastating to farmers and the potato industry as a whole. A large proportion of these crop losses are due to factors such as rapid water loss and disease while in storage.

In 2013, approximately 33 percent of the U.S. crop was lost, which equated to $1.2 billion in lost profits for farmers. Kosma, assistant biochemistry professor, and Santos, assistant research professor, are focusing their research on reducing this number.

“Even a 5 percent reduction in potato losses during storage would improve the economic return for the producers and the potato industry by $170 million,” Kosma said.

The research delves into comprehending how different potato varieties can have different storage lives. They are using one variety that stores very well and another that stores very poorly to understand the molecular basis of this differential storage capacity. From a basic science perspective, no one has yet figured this out.

Specifically, Kosma is interested in the corky lipid polymer that comprises a large proportion of the skin. This polymer is referred to as “suberin.” Suberin can be found in nearly every plant, and although it is widespread, there is still little known about its makeup and function.

Kosma and Santos want people to know that potatoes do not just go straight from the field to the store. Potatoes are grown and harvested in the fall and kept in cold storage until sold and distributed. The problem occurs when potatoes are not stored properly, which then impacts profits.

When potatoes are harvested in the field, they tend to get damaged and form “scabs” or wound periderm that prevent the sugars and water from coming out and also keeps bacteria and fungi from getting in. This wound-healing tissue is made up of suberin. These are the rough raises we tend to see on potatoes from the supermarket. It is important for potatoes to form this wound-repairing tissue to prolong storage life.

The idea of this research is to ultimately improve how potatoes heal with this wound suberin deposition and how to, in turn, improve their lasting storability.

A native of Illinois, Kosma showed an interest in plant biology from a young age. Although he jokes that he was not tremendously influenced by potatoes growing up, he always enjoyed going outside to forage wild foods and plants for both fun and to satisfy his general curiosity about the natural world. He received both his bachelors and master’s degrees in plant biology from Southern Illinois University, and furthered his education at Purdue University, where he received his doctorate degree. His post-doctorate work led him to Michigan State University where he met Santos, his wife and research partner. Santos, an assistant research professor, has an emphasis in plant pathology with specific interests in plant-microbe interactions.

Both are interested in plant stress tolerance in relation to the environment, and found that Nevada well suited those research interests. They have been a part of the Department of Biochemistry and Molecular Biology at the University of Nevada, Reno for two years, having moved here in January 2015.

The two are extremely passionate about their work, and this project is something that had been stewing in Kosma’s thoughts well before their move to Nevada.

“In Michigan, two years prior to moving here Dylan was already talking about writing a project about potatoes and how cool it would be,” Santos said.

Since then, their research team has grown to include: Professor Karen Sclauch, who specializes in bioinformatics at the University; Professor Dave Douches, a potato breeder out of Michigan State University; and Professor Ray Hammerschmidt, a plant pathologist also from Michigan State. They have one graduate student and numerous undergraduates working with them in their lab.

The $1.37 million National Science Foundation grant will keep this research going for the next four years.