Development of Genomic Resources to Facilitate the Domestication of Silphium integrifolium as a Perennial Oilseed Crop

The domestication of wild plant species presents a number of opportunities to fill new agricultural niches, but also a number of challenges. Historically, domestication took place over many human generations, but leveraging modern genomics and genetics will significantly reduce the time necessary to domesticate new crops. Here, we present basic breeding-oriented genomic resources towards the domestication of the wild sunflower relative Silphium integrifolium for use as a perennial oilseed crop. We have developed a draft linkage map from 77 F1 individuals, where 330 out of 548 SNP markers were resolved into 17 linkage groups. Additional work will be needed to resolve these into the seven physical S. integrifolium chromosomes. We used these markers to study synteny with the Helianthus annuus genome. 204 of the markers assigned to a linkage group mapped with a high level of confidence to the H. annuus genome, and 10 linkage groups showed regions of synteny. We have also developed an association mapping panel that represents the breadth of the S. integrifolium breeding germplasm available. To assess the level of linkage decay in this population, a subset of cosegregating and tightly linked markers identified in our linkage map will be genotyped using KASP markers. Ultimately, we will use this information to assess the suitability of our panel for mapping domestication traits in S. integrifolium, which will provide the foundation for continued domestication and breeding of S. integrifolium as a perennial oilseed crop.