Mapping of the Barley and Bread Wheat Genomes

Together with international partners, a team of the Department of Plant Genome and Systems Biology has created ordered sequence resources of the highly complex genomes of barley and bread wheat. Both crops are of enormous importance.

In the framework of the International Barley Sequencing Consortium, scientists at the Helmholtz Zentrum München have made a major contribution to deciphering and analyzing the barley genome and to develop new approaches for molecular breeding.

The research of the International Barley Sequencing Consortium, which along with other partners, includes scientists led by Klaus Mayer at the Department of Plant Genome and Systems Biology, provides a detailed view into the barley genome. For the first time a high-resolution genome overview was created for a genome that by far exceeds the size of the human genome. In addition, the team was able to gain insight into gene regulation and make comparisons between wild barley and cultivated strains. Thus, an in-depth molecular understanding of the inventory of cereal genomes and a first glimpse into molecular circuits was obtained. The findings are seen as an important basis to accelerate the breeding of barley varieties that e.g. show improved resistance or are better adapted to climate change. At the same time, the barley genome served the researchers as model for the more complex bread wheat genome. Here the team headed by Klaus Mayer, together with British scientists from the Universities of Bristol und Liverpool and the John Innes Centre carried out and published a first genome analysis. Along with rice and corn, wheat is the most important cereal crop. The bread wheat genome is hexaploid (contains six copies) and contains approximately 96 000 genes. Due to its size and complexity, it has not yet been fully sequenced. The now published genome gene atlas is an important step towards understanding the interplay of the different genome copies of this cereal and to enable molecular breeding even for wheat.

Barley is one of the earliest domesticated and most important cereal crops. The barley genome is diploid, contains slightly more than 26 000 genes and includes 5.1 billion base pairs (5.1 Gb). The bread wheat genome, with 17 billion base pairs (17 Gb), is not only much larger but also contains considerably more genes – approximately 96 000. A wheat cell is hexaploid and has six copies of its chromosomes.