Global Researchers Collaborate to Advance the Mapping of the Barley Genome

The advance will give researchers the tools to produce higher yields, improve pest and disease resistance, and enhance nutritional value of barley.

18 Oct 2012 --- In a major advance that will unlock the benefits of the mapping of the barley genome--one of the world's most important cereal crops--work conducted and supported by the U.S. Department of Agriculture (USDA) in collaboration with researchers around the world has resulted in the most advanced sequencing of the barley genome to date, as reported today in the journal Nature. The advance will give researchers the tools to produce higher yields, improve pest and disease resistance, and enhance nutritional value of barley. Past genomic research supported by USDA has provided similar benefits to crops such as tomato and corn, and helped improve cattle breeding and enhance the productivity of dairy cows.

"USDA supports innovative genomics research that is really moving us forward to meeting the many challenges we face in food, fuel and agriculture production," said Catherine Woteki, USDA's Chief Scientist and Under Secretary for Research, Education, and Economics. "This important step toward full barley genome sequencing offers enormous potential for global food security. Using the tools of genetics and genomics, we are keeping farmers profitable and our food supply safe and abundant."

Along with project investigators Timothy Close and Stefano Lonardi at the University of California, Riverside (UCR) and Gary Muehlbauer at the University of Minnesota, supported by grants from USDA's National Institute of Food and Agriculture (NIFA), USDA's Agricultural Research Service (ARS) scientists Roger Wise and Jesse Poland, together with scientists from 19 other organizations around the world, make up the International Barley Sequencing Consortium (IBSC).

Nearly twice as large as the human or maize genomes, the barley genome was a challenge to sequence, due to its complexity and its large proportion of repetitive regions, which are difficult to piece together into a true linear order. By developing and applying a series of innovative strategies that allowed them to circumvent these difficulties, the IBSC created a high-resolution assembly that places the majority of barley genes in order. This new resource provides the sequences of nearly all genes and associated regulatory regions, which will offer new direction to researchers seeking to improve barley yield and quality through functional genomics (determining the functions of important barley genes) and genomics-assisted breeding.

The work of IBSC highlighted in Nature provides a detailed overview of the functional portions of the barley genome, revealing the order and structure of most of its 32,000 genes and a detailed analysis of where and when genes are switched on in different tissues and at different stages of development. They describe the location of dynamic regions of the genome that carry genes conferring resistance to devastating diseases, such as powdery mildew, Fusarium head blight and rusts. This will provide a far better understanding of the crop's immune system. The achievement will also highlight with unprecedented detail the genetic differences among barley cultivars.

The success of the barley genome sequencing, and other grass family crops including wheat and rye, will allow breeders and scientists to effectively address the challenge of feeding the world's growing population living in an environment that increasingly challenges farmers and ranchers with extreme weather events.

The research, published in the journal Nature, will also help to produce new and better barley varieties that are vital for the beer and whisky industries.

The UK team behind the research was led by Professor Robbie Waugh of Scotland's James Hutton Institute who worked with researchers at The Genome Analysis Centre, Norwich.

Barley is the second most important crop in UK agriculture and malting barley underpins brewing and pub industries worth some £20 billion to the UK economy. The breakthrough is a critical step towards barley varieties able to cope with the demands of climate change. It should also help in the fight against cereal crop diseases that cause millions of pounds of losses annually.

Barley is the world's fourth most important cereal crop both in terms of area of cultivation and in quantity of grain produced. In addition to whisky and beer, barley is also a major component of the animal feed for meat and dairy industries. Barley straw is a source of nutrition for ruminants and is used for animal bedding and frost protection in the winter.

The barley genome is almost twice the size of that of humans and determining the sequence of its DNA has presented a major challenge. This is largely because its genome contains a large proportion of closely related sequences that are difficult to piece together into a true linear order.

By developing and applying a series of innovative strategies that allowed them to circumvent these difficulties, the International Barley Genome Sequencing Consortium (IBSC) - including UK researchers in Dundee and Norwich and funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and Scottish Government - has managed to construct a high resolution draft DNA sequence assembly that contains the majority of barley genes in linear order.

Their publication provides a detailed overview of the functional portions of the barley genome, revealing the order and structure of most of its 32,000 genes and a detailed analysis of where and when genes are switched on in different tissues and at different stages of development. They describe the location of dynamic regions of the genome that, for example, contain genes conferring resistance to diseases. This will provide a far better understanding of the crop's immune system. The achievement also highlights with unprecedented detail the differences between several different barley cultivars.

Professor Waugh commented: "Access to the assembled catalogue of gene sequences will streamline efforts to improve barley production through breeding for varieties better able to withstand pests and disease and deal with adverse environmental conditions such as drought and heat stress.

"It will accelerate research in barley, and its close relative, wheat. Armed with this information breeders and scientists will be much better placed to deal with the challenge of effectively addressing the food security agenda under the constraints of a rapidly changing environment."

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11543.html