Laura Shannon

Potato Breeding

Potatoes are the largest non-grain crop in the world and Minnesota growers produce about 2 billion pounds of potatoes a year in all market classes. We develop new potato cultivars to address changing environmental, disease, and market pressures and meet the needs of Minnesota’s diverse growers.

The traditional breeding processes for potatoes is slow because cultivated potatoes in the US are clonal tetraploids. In the Shannon lab, we leverage genetic data and enhancing our understanding of tetraploid genetics to speed this breeding process through marker-assisted selection.

Potato 2.0 

One way to speed the potato breeding process is to reduce ploidy.  In collaboration with potato breeders across the US and internationally we are developing diploid potatoes. Our first step is to develop diploid germplasm by crossing tetraploid germplasm to a diploid inducer and introgressing self-compatibility genes. In the long term, this will allow potato breeders to take advantage of the tools and techniques available in other crops like inbred-hybrid breeding and introgression. Along the way, it will provide opportunities to better understand the potato genome at both the diploid and tetraploid level. 

Potato Domestication and Diversity

Cultivated potato consists of multiple species (taxonomists disagree about how many) ranging from diploid to pentaploid, these were domesticated from a complex of wild Peruvian species. The history of potato improvement has involved continual introgression from wild species into the cultivated germplasm and selection for distinct morphologies. We use population and quantitative genetics to unravel this history based on the signatures it leaves in the genome. In the process, we discover how autopolyploidy and clonal reproduction affect evolutionary genetic patterns.