History and future perspectives of barley genomics

Barley (Hordeum vulgare), one of the most widely cultivated cereal crops, possesses a large genome of 5.1 Gbp. Through various international collaborations, the genome has recently been sequenced and assembled at the chromosome-scale by exploiting available genetic and genomic resources. Many wild and cultivated barley accessions have been collected and preserved around the world. These accessions are crucial to obtain diverse natural and induced barley variants. The barley bioresource project aims to investigate the diversity of this crop based on purified seed and DNA samples of a large number of collected accessions. The long-term goal of this project is to analyse the genome sequences of major barley accessions worldwide. In view of technical limitations, a strategy has been employed to establish the exome structure of a selected number of accessions and to perform high-quality chromosome-scale assembly of the genomes of several major representative accessions. For the future project, an efficient annotation pipeline is essential for establishing the function of genomes and genes as well as for using this information for sequence-based digital barley breeding. In this article, the author reviews the existing barley resources along with their applications and discuss possible future directions of research in barley genomics.