Researchers map complete sunflower genome

Researchers published the complete sunflower genome in Nature today, a major step toward improving the crop’s genetic diversity and ability to withstand climate change.

The $20 billion, healthy oilseed crop holds great promise for climate change adaptation. It can grow and flourish across a diverse range of environmental conditions, including drought.

“This is one of the most challenging genomes published to date,” says University of British Columbia professor Loren Rieseberg, a senior author on the paper.

“Not only have we sequenced sunflower’s genome but we’ve built physical and genetic maps of its structure, which increases the genome’s value for research and breeding.”

Cultivated sunflowers are one of the five largest oilseed crops in the world, and the last of these crops to have its genome fully sequenced.

In evolutionary biology the sunflower is a long-time model for research on how new species arise, and in plant science the sunflower is a model for understanding solar tracking and plant growth.

Despite this large interest, assembling the sunflower genome has been extremely difficult. Between 70 and 80 percent of the plant’s genome is made up of repeating regions and this complexity has challenged leading-edge assembly protocols for close to a decade. The sunflower genome is about 10 per cent larger than the human genome. The challenge, however, is that the duplications in the sunflower are both longer and younger (more similar to each other) than in the human genome.

The publication of the sunflower genome in Nature comes after two major investments in sunflower genomics, totaling over $18 million, by Genome British Columbia (Genome BC), Genome Canada and other funders in 2009 and 2015.

“We congratulate Dr Rieseberg and the entire team on this accomplishment,” says Dr Catalina Lopez-Correa, Chief Scientific Officer and Vice President, Sectors, at Genome BC.

“Our investment will have significant benefits to academic and industry stakeholders because this information will help to inform the development of strains with stress-resistant traits like resistance to drought and low nutrients, enabling them to grow in dry and degraded soils. Such resistance traits will be key to increasing food production under climate change, especially in demanding environments like those found in sub-Saharan Africa.”