Scientists Advance Barley Genome Mapping

WASHINGTONU.S. Department of Agriculture (USDA) scientists, in collaboration with the International Barley Sequencing Consortium (IBSC), have advanced the mapping of the barley genome, which will give them the tools necessary to produce higher yields, improve pest and disease resistance, and enhance nutritional value of barley.

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.

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 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 thee difficulties, the IBSC created a high-resolution assembly that places the majority of barley genes in order. The 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 and genomics-assisted breeding.

The work, highlighted in the journal 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.

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.