Finding hidden genetic treasure: Research reveals untapped diversity in historic wheat collections

A decade of collaborative research has uncovered vast untapped genetic potential in modern wheat varieties. An international study that appears in Nature shows that at least 60% of the genetic diversity found in the historical collection of wheat is underutilized, providing an unprecedented opportunity to improve modern wheat and sustainably feed the world’s growing population.

To make this discovery, the collaboration of various institutions led by Dr. Simon Griffiths, at the John Innes Center and Professor Shifeng Cheng at the Institute of Agricultural Genomics in Shenzhen, Chinese Academy of Agricultural Sciences (CAAS), studied the AE Watkins Landrace Collection, a historic collection of non-domesticated landrace varieties. again anywhere in the world and compared to modern folklore.

The success is the result of joint efforts of the union. Cheng says, “We built a collaborative and complementary consortium with full transparency, making resources in genetic, genomic and phenotypic databases publicly available through the Watkins Worldwide Wheat Genomics to Breeding Portal (https://wwwg2b.com/). Efforts ours has facilitated and accelerated many existing projects in basic research and breeding.”

One of the key factors that contributed to the success was extensive testing, including test stations from the UK (three locations) and field evaluation (five locations) from north to south China. In total, 137 characteristics were examined in this study. This work was supported in particular by Rothamsted Research, which acted as a phenotyping hub to increase understanding of wheat traits and characteristics, cross-breeding and genetic sequencing.

The team created a wheat mutation map, a haplotype-phenotype association map. A cross-farm comparison revealed that modern wheat varieties utilize only 40% of the genetic diversity found in the Watkins Collection.

The remaining diversity represents a gold mine with the potential to improve modern wheat, says Dr. Griffiths, group leader at the John Innes Center, and author of the paper, “This missing 60% discovered in this study is full of beneficial genes that we need to feed people sustainably. Over the past ten thousand years, we have tended to select for traits that increase yield and improve disease resistance.

“We have found that the Watkins landraces are full of important differences that are not present in modern wheat, and it is important to carry this forward into modern breeding. What is exciting is that genes and traits are already being discovered using data and tools. Developments in the last decade.”

The AE Watkins landrace collection of bread wheat (Watkins collection) collected in the 1920s and 1930s from 32 countries, represents the most comprehensive collection of historic wheat anywhere in the world.

The collection provides a snapshot of the variety of wheat cultivated before the advent of modern, systematic plant breeding and shows how genetic variation is dispersed among populations, or ancestral groups, around the world.

“We can bring back the novel, functional and useful diversity that was lost in modern wheat after the ‘Green Revolution’ in the 20th century, and have the opportunity to add them to elite breeding programs,” says Professor Cheng.

Genomics and bioinformatics analysis completed by researchers at the Institute of Agricultural Genomics in Shenzhen, allowed the consortium to see where modern wheat originated. They found that globally, wheat varieties originated in central and western Europe, with only two of the seven ancestral groups in the Watkins collection used in modern plant breeding.

Using three association genetic methods (QTL mapping, GWAS and NAM GWAS), the team identified hundreds of unique Watkins cultivars that could provide superior traits in modern wheat, informing breeders which genes carry important loci or alleles. in their breeding. program.

Key traits already found in this untapped variety include nitrogen use efficiency, slug resistance and resistance to pests and diseases.

Dr. Griffiths adds “There are genetics that will enable plant breeders to increase the efficiency of nitrogen use in wheat. If we can find these in modern varieties that farmers can plant, they will have to apply less fertilizer, save money and reduce carbon emissions. .”

The use of fertilizers in agriculture is expensive and contributes to the emission of greenhouse gases, reducing its use can help agriculture move towards net zero. Improving the efficiency of nitrogen use in crops and reducing the amount of nitrogen in agriculture is currently a big challenge worldwide, especially for countries like China.

To achieve this unprecedented research breakthrough, the team developed a core set of 119 loci that represented the breadth of genetic variation within the Watkins collection. This diverse set was backcrossed to modern wheat to form a collection of 12,000 wheat lines now housed in the Germplasm Resource Unit at the John Innes Centre.

This means that for the first time in 100 years these lost traits have been incorporated into modern wheat, and data and tools are already being used to improve crops.

This study establishes the first whole-genome design breeding system for wheat by integrating genomics and phenomics with breeding practices. “We implemented a breeding strategy before deciphering, discovering, designing and making progress in breeding,” says Dr. Griffiths.

“Obviously, the genomics revolution is leading to a genetic revolution and a breeding revolution,” says Cheng. This research was truly collaborative, long-term, and could not have been completed without international cooperation.

In collaboration with UK commercial plant breeders, the team has developed a freely available breeder’s toolkit, a set of online resources that are open source and available globally for anyone to use. The toolkit provides an integrated set of tools for research and breeding communities, allowing others to access and use new, profitable varieties to produce sustainable, resistant wheat now and in the future.

These cells, resources and equipment developed in this research, are still being further investigated in various experimental centers in China. These efforts are expected to contribute greatly to the improvement of wheat genetics and breeding in China.