Researchers at the Land Institute and the HudsonAlpha Institute for Biotechnology have produced the first chromosome-scale, haplotype-phased genome assemblies for two wild North American prairie plants: Silphium integrifolium and Silphium perfoliatum. The work, published in Nature Communications, lays the genomic groundwork needed to domesticate these deep-rooted giant sunflower species into perennial crops.
The stakes are notable given how narrow the world’s food supply already is: more than half of all human calories come from just five crops—rice, wheat, corn, sugarcane, and barley. Perennial species like Silphium, which regrow for multiple years after a single planting, could add diversity and productivity to that supply while also benefiting the ecosystems they grow in.
According to senior author David Van Tassel, wild perennials “could help improve food security by contributing sustainability-enhancing traits such as deep roots,” and that genomic-informed breeding “will help generate new crop varieties more quickly than in the past,” even in “a stubborn genus that previously resisted genome assembly.”
The genomes themselves are enormous—7.6 gigabases for S. integrifolium and 7.5 for S. perfoliatum—with individual chromosomes among the largest recorded in plants, organized by an unusual helical DNA structure the team identified. Mapped genetic markers for traits such as drought tolerance, heat adaptation, and seed yield should let breeders domesticate Silphium faster while retaining its wild resilience. S. integrifolium in particular stands out as a potential oilseed crop, with seeds yielding 11.8 to 25.3 percent edible oil and containing squalene, used in vaccines and cosmetics. Ecologically, Silphium roots can reach 4.5 meters deep, helping stabilize soil, build organic carbon, and improve water infiltration and drought resilience.
First author Renan Souza explained that the urgency behind the work comes from “the growing instability of climate patterns and disruptions in global food supplies,” adding that the genomic framework “will help speed up the improvement of not only Silphium, but also other wild species with agricultural potential.”
The team also developed a DNA fingerprinting method breeders can use to select for traits like disease resistance and seed head size, and to identify genetic diversity hotspots. Next steps include scaling fingerprinting to thousands of plants annually and further studying the chromosomes’ unusual structure.
The stakes are notable given how narrow the world’s food supply already is: more than half of all human calories come from just five crops—rice, wheat, corn, sugarcane, and barley. Perennial species like Silphium, which regrow for multiple years after a single planting, could add diversity and productivity to that supply while also benefiting the ecosystems they grow in.
According to senior author David Van Tassel, wild perennials “could help improve food security by contributing sustainability-enhancing traits such as deep roots,” and that genomic-informed breeding “will help generate new crop varieties more quickly than in the past,” even in “a stubborn genus that previously resisted genome assembly.”
The genomes themselves are enormous—7.6 gigabases for S. integrifolium and 7.5 for S. perfoliatum—with individual chromosomes among the largest recorded in plants, organized by an unusual helical DNA structure the team identified. Mapped genetic markers for traits such as drought tolerance, heat adaptation, and seed yield should let breeders domesticate Silphium faster while retaining its wild resilience. S. integrifolium in particular stands out as a potential oilseed crop, with seeds yielding 11.8 to 25.3 percent edible oil and containing squalene, used in vaccines and cosmetics. Ecologically, Silphium roots can reach 4.5 meters deep, helping stabilize soil, build organic carbon, and improve water infiltration and drought resilience.
First author Renan Souza explained that the urgency behind the work comes from “the growing instability of climate patterns and disruptions in global food supplies,” adding that the genomic framework “will help speed up the improvement of not only Silphium, but also other wild species with agricultural potential.”
The team also developed a DNA fingerprinting method breeders can use to select for traits like disease resistance and seed head size, and to identify genetic diversity hotspots. Next steps include scaling fingerprinting to thousands of plants annually and further studying the chromosomes’ unusual structure.