Researchers crack bread wheat genome code

BETHESDA, MARYLAND, U.S. — The International Wheat Genome Sequencing Consortium (IWGSC) on Aug. 16 published a detailed description of the genome of bread wheat, an effort that researchers believe will pave the way for the development of wheat varieties that are better adapted to climate challenges, have higher yields and enhanced nutritional quality, and improved sustainability.

The description of the genome of the bread variety Chinese Spring appears in the international journal Science. An explainer video is available here.

The findings represent 13 years of collaborative international research from more than 200 scientists from 73 research institutions in 20 countries, the IWGSC said.

According to the IWGSC, the completion of the reference genome sequence will give breeders more tools at their disposal to address the many challenges that face wheat and its role in global food security. The IWGSC cited data suggesting wheat productivity needs to increase by 1.6% each year to meet the demands of a global population that is expected to reach 9.6 billion by 2050.

With the genome, the hope is that breeders now will be able to identify more rapidly genes and regulatory elements underlying complex agronomic traits such as yield, grain quality, and resistance to fungal diseases, the IWGSC said.

 “The wheat genome sequence lets us look inside the wheat engine,” said Rudi Appels, University of Melbourne and Murdoch University Professor, and AgriBio Research Fellow. “What we see is beautifully put-together to allow for variation and adaptation to different environments through selection, as well as sufficient stability to maintain basic structures for survival under various climatic conditions.”

The bread wheat genome not only is huge — it’s five times larger than the human genome — it’s also complex, and researchers for many years considered breaking the code a near impossible task. The IWGSC said it expects industry to see benefits similar to those observed with corn and rice after their reference sequences were produced.

“The publication of the wheat reference genome is the culmination of the work of many individuals who came together under the banner of the IWGSC to do what was considered impossible,” said Kellye Eversole, executive director of the IWGSC. “The method of producing the reference sequence and the principles and policies of the consortium provide a model for sequencing large, complex plant genomes and reaffirms the importance of international collaborations for advancing food security.”

In addition to the sequence of the 21 chromosomes, the Science article also presents the precise location of 107,891 genes and of more than 4 million molecular markers, as well as sequence information between the genes and markers containing the regulatory elements influencing the expression of genes.

Publication of the complete genome of bread wheat elicited strong responses across the industry.

“It is a dream come true for Kansas wheat farmers, who were the first to invest in the wheat genome sequencing project and were pivotal in rallying U.S. wheat farmers in support of the wheat genome sequencing project,” said Bikram Gill, distinguished professor emeritus of plant pathology at Kansas State University who organized the first National Science Foundation and U.S. Department of Agriculture-sponsored workshop planning meeting on wheat genome sequencing in Washington, D.C., in 2003.

Jesse Poland, associate professor at KSU and director of the Wheat Genetics Resource Center and the U.S. Agency for International Development Innovation Lab for Applied Wheat Genomics, said it was “exciting” to be a part of the landmark achievement.

“This international effort, toward something that was once deemed impossible, will have tremendous impact on wheat in Kansas, and the world,” Poland said.

Curtis Pozniak, researcher and wheat breeder at the Crop Development Centre in the University of Saskatchewan’s College of Agriculture and Bioresources, said he was proud to be part of a research team that made a discovery with the potential for “disruptive innovation in wheat improvement.”

“Essentially we have completed the wheat genome jigsaw puzzle with all the pieces put together in their correct positions and order, providing an enormous advantage for breeders when searching for genes that control important traits in the crop,” Pozniak said. “This breakthrough research will help produce better wheat varieties over the long term.”

With the wheat genome now sequenced, the IWGSC said the next step will be focusing on producing a genome-sequenced based toolbox for breeders and scientists to use for wheat improvement. The IWGSC said researchers will undertake several projects, including maintaining and improving the current reference genome to ultimately produce a “Gold Standard” reference genome sequence that is manually and functionally annotated; sequencing other varieties of wheat to represent the worldwide diversity of wheat; and continuing to develop a database for the wheat community to access all the genomic resources.

The IWGSC, with 2,400 members in 68 countries, is an international, collaborative consortium, established in 2005 by a group of wheat growers, plant scientists, and public and private breeders. The goal of the IWGSC is to make a high-quality genome sequence of bread wheat publicly available to lay a foundation for basic research that will enable breeders to develop improved varieties.

Source: WORLD-GRAIN.COM