A major international research collaboration has revealed what makes wheat tick, promising discoveries to combat disease and produce higher yields more sustainably in tough conditions.
More than 200 scientists from 73 research institutes in 20 countries over 13 years have produced the most comprehensive map of a wheat genome, paving the way for more resilient and nutritious varieties of a staple crop that feeds more than a third of the global human population.
The detailed findings, published in Science, describe more than 94% of the genome of Chinese Spring, a variety of bread wheat (Triticum aestivum), which is the world’s most widely cultivated crop. But all wheat varieties will benefit from the knowhow.
The project has been an immense challenge, acknowledges the International Wheat Genome Sequencing Consortium (IWGSC), which co-ordinated work. The wheat genome is five times the size of the human genome, with now well over 100,000 genes and more than 4 million molecular markers already identified and positioned across 21 chromosomes in three sub-genomes.
“For me, as a functional genomics and genetics researcher, having a continuous and fully annotated sequence for each of the 21 wheat chromosomes is of paramount importance,” says Kostya Kanyuka who, with bioinformatician Rob King, represented Rothamsted Research in the IWGSC.
“This will greatly speed up our efforts on identification of agriculturally important wheat genes, including those that would help to combat major fungal diseases,” notes Kanyuka. “This will also be hugely and immediately beneficial for wheat breeders, accelerating development of new elite varieties.
Kanyuka and King provided manual annotation and curation of all genes belonging to two large families, Amino Acid Transporter (AAT) and Wall Associated Kinase (WAK), which are particularly important for wheat breeding and improvement.
Wheat productivity needs to increase by 1.6% a year to meet the demands of a projected world population of 9.6 billion by 2050. And to preserve biodiversity, water and nutrient resources, the world needs to produce more from existing cultivated land rather than cultivate more land.
Wheat breeders now have new tools at their disposal to address these challenges. They will be able to identify more rapidly factors that underlie agronomic traits, such as yield, grain quality, resistance to fungal diseases and tolerance to abiotic stress, and produce hardier wheat varieties.
“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,” says Kellye Eversole, IWGSC’s Executive Director.
“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,” notes Eversole.
Details of this high-quality reference genome sequence are expected to boost wheat improvement over the next decades, with benefits similar to those observed with maize and rice after their reference sequences were produced.