The Future of Diploid Potatoes
February 1, 2023
A new movement is happening in the potato industry: simplifying the potato genome. Growers around the country have experienced the effects of unpredictable weather, which impacts production and profitability, and consumers continually shift their wants, requiring changes from potato processors. These uncontrollable factors explain why breeding is important. The industry has a team of 11 individuals from seven institutions and USDA’s Agricultural Research Service (ARS), dedicated to increasing the likelihood of genetic improvement through a project known as Potato 2.0, and education about diploids to increase the likelihood of grower adoption.
Genetics are largely responsible for the breeding difficulties associated with potatoes. While many crops hold two copies of chromosomes, potatoes astoundingly contain four copies, disrupting what most people know and understand about the fundamentals of genetics. The additional set of chromosomes leads to slow and meticulous breeding practices. To simplify the breeding process, a team of researchers has been studying the genetic processes of moving from tetraploids (four chromosomes) to diploids (two chromosomes) and are making significant progress. In the first four years, the team geared up for and executed a trial with diploid potatoes to measure, evaluate, and optimize the process. In the fifth and final year of the project, the team will continue to develop a breeding system that is responsive to grower and market needs while putting effort into market traits to compete with traditional tetraploid lines.
Diploid potatoes are not a novel concept. China and Europe have engaged in their own diploid potato experiments. With environmental changes, it’s universally understood that optimizing control in the breeding process must happen.
Growers will experience additional benefits from genetically simplified potatoes such as disease resistance and other quality traits. Moving from four to two chromosomes increases the probability of desired varieties and ultimately improves profitability for growers and processors. For example, genes have been identified that contribute strong, multi-strain resistance to late blight. Breeding for these genes could result in greater potential for durable late blight resistance.
While there are many reasons to be excited about the evolution of potato breeding, skepticism exists surrounding diploid potatoes. Growers have expressed fear of introducing diploids to their fields and harvesting tubers that look, feel, and process strangely. However, the team has conducted experiments with seasoned potato growers. The growers were given multiple tubers and asked to determine which tuber was the diploid variety. To the participants’ surprise, most were unable to identify the diploid. In addition to disrupting misconceptions about the appearance of diploids, the team is also interested in providing education on the consistency of growing and harvesting between tetraploids and diploids – such as not needing additional or alternative harvest equipment. Challenging misconceptions is always difficult, but this does not deter the team from making diploids a reality.
To learn more about diploids, scan the QR code to learn more about the project and the team.