Using Whole-Genome Sequences for Breeding Climate Resilient Cereals

Cereals are vital components of the diets of humans, contributing around 42% of total calories, of which nearly 90% are provided by bread wheat (Triticum aestivum) and rice (Oryza sativa).  To meet the demands of a global human population expected to exceed 9.6 billion by 2055, wheat and rice production must expand significantly in the face of a steadily changing climate and increased biotic and abiotic stressors.  Both crops will need a full complement of genetic and genomics resources to enable systematic improvements.  Currently, rice is the only crop with a finished genome sequence and the advantages this confers with respect to molecular understanding of genetic diversity and interactions with the environment are becoming apparent.  Achieving a high quality reference sequence of the bread wheat genome is proving a much greater challenge because of the cost and bioinformatics complexity of assembling a large, 17Gb, hexaploid genome containing over 85% repetitive sequences.  To reduce the complexity, the IWGSC is following a chromosome-specific approach to generate physical maps, draft sequences, and BAC-based reference sequences. Already, the IWGSC resources are being used to accelerate gene discovery and breeding for traits related to climate change. Examples of how wheat and rice genomics resources are being used to develop climate resilient varieties will be presented.