NORWICH, England – A vast collection of landrace wheat samples representing wheat before breeding may be the secret to improving modern wheat crops.

Simon Griffiths, group leader of the Delivering Sustainable Wheat program at the John Innes Centre in the United Kingdom, and his team worked for over a decade to understand how modern wheat differs from landraces.

“We began (producing wheat) in the Fertile Crescent, so coming down from Turkey through Mesopotamia and around to Israel, where it was domesticated,” Griffiths said. “Then it spread around the world from there, and that was only 10,000 years ago. But in those 10,000 years, obviously, people selected wheat for all sorts of extreme environments.”

The selection of wheat for certain traits simultaneously across the globe led to the loss of landraces. Today, many crops are produced by breeding companies focused on high yield. Griffiths wanted to know if any useful variations from the landraces had been left behind in modern wheat.

To do so, the team utilized a vast collection of landrace wheat samples that began in the 1920s in England when a scientist convinced the London Board of Trade to collect wheat samples. This resulted in a collection of 7,000 wheat samples from 32 countries. Over the years, the collection dwindled to 827 samples due to moth damage, disruption in upkeep during World War II, and the fact that dehumidification and refrigeration for seed storage didn’t arrive until much after the collection was begun.

The team sequenced the genomes of all 827 landraces and 208 modern cultivars for comparison. First, they compared the landrace sequences to a reference wheat genome representative of modern wheat.

“We take the sequences of the landraces and align it to the reference, and that immediately allows us to say how many of the (genetic) variants in the landraces are absent in modern wheat,” Griffiths said. “That was the real moment we knew we were onto something because 60 percent (of the variants) were not present in modern wheat.”

Griffiths and his team found seven ancestral groups to which the landraces could be assigned. Today, only two of the seven groups are present in modern wheat varieties, representing a loss of genetic diversity from crops adapted to arid environments and different disease pressures across the globe.

The team discovered a variety of beneficial traits from the landraces that they could map to specific genes. Griffiths said that the team found genes related to increased yield, increased resistance to strip rust and septoria, and increased nutritional benefits like calcium, zinc and iron.

Additionally, some of Griffiths’ colleagues have cloned a gene for resistance to wheat blast, a devastating fungal disease that is currently spreading in the tropics. Griffiths likened using all this data as a tool to look into the past to solve the problems of our present and future. The data from this project allow researchers to identify genes for almost any trait desirable for wheat.

Griffiths said that the team is also working directly with farmers in the UK to study landrace diversity. Slugs are putting a lot of pressure on crops, and many chemicals used to eliminate slugs are banned in the UK. Griffiths said that they screened the landraces collection for slug resistance. They found a variety resistant to slugs and worked with 12 farms across the country to plant the ancient landrace. The first year of the study was so dry that there was no slug pressure, but the research team noted early slug pressure last year. After slug monitoring and data analysis, the team concluded that slugs don’t like that ancient landrace and will leave it alone.

Researchers and breeders can access all of the genomic data and resources from the project at no cost, as well as seeds from the landraces. However, it may be some years before ancient wheat traits are widely used in modern wheat varieties. There are barriers to combining novel findings from studies of landraces within a single variety. New innovations in breeding technology are needed to introduce new traits while maintaining the optimal combinations already present in modern varieties.

Still, Griffiths is confident that this work is important for the evolving world and will beneficially impact wheat producers. Producers must balance scaling wheat production for a growing population while minimizing greenhouse gases.

“We’re not saying, ‘Well, the answer is genetic diversity’, but I’m convinced this will contribute to (solving global challenges),” he said.