Estimating Genetic Diversity and Population Structure of Founder Lines in a Pennycress Breeding Program.

The conventional agriculture system in the U.S. faces major challenges including the need to increase production on less land while managing a changing climate and improving sustainability. In order to face these challenges, we must increase the productivity and profitability of our current agriculture system in ways that are easy and useful for farmers. For example, a cover crop that protects the soil over the winter and produces a marketable crop could be a major incentive for farmers to prevent soil erosion and water pollution. The winter annual oilseed, field pennycress (Thlaspi arvense L.), could be easily integrated into our production systems to protect the soil from fall to early spring when it can be harvested to provide an early cash crop. The University of Minnesota Pennycress breeding program began in 2013 with the goal of developing high yielding, non-shattering, fast germinating, and winter hardy pennycress varieties. The foundation of this breeding program is 126 spring and winter annual pennycress accessions collected by the by the National Genetic Resources Program and faculty at UMN. We used genotyping-by-sequencing to estimate the genetic diversity and population structure of the founding pennycress accessions as well as to investigate genetic control of flowering time. This data has been used to inform breeding program decisions such as crossing plans to maintain genetic diversity while rapidly improving this new crop species. This combination of traditional and advanced breeding tools will allow us to rapidly develop a new cash cover crop for the Upper Midwest.