Date: Saturday, January 14, 2012
Time: 9:30 AM
Time: 9:30 AM
Room: Royal Palm Salon 5-6
Wheat is a major export crop for Australia, but yields are often limited by abiotic stress, with water availability being the major limiting factor. Climate change is likely to impact the reliable production of wheat in Australia and the breeding of cultivars for Australia’s harsh climate is a priority for Australian crop researchers. The genome of bread wheat (Triticum aestivum) is greater than 16 Gbp in size and consists predominantly of repetitive elements, features which limit the application of molecular or genomic tools for wheat improvement. Second generation sequencing technologies and applied bioinformatics tools can provide an unprecedented insight into genome structure, variation and function, though there has been some debate over whether second generation sequencing can be applied for such a large and complex genome. We have reduced genome sequence complexity by sequencing isolated chromosome arms, with the aim to assemble low copy and genic regions. Our approach enabled the assembly of all genes, as well as a substantial portion of the repetitive fraction. The syntenic relationship between wheat and a sequenced close relative, Brachypodium distachyon,has been used to produce annotated syntenic builds whereby the majority of genes have been placed in an approximate order and orientation. A study of differential gene expression and gene loss between homeologous chromosomes reflects the known evolution of this complex genome. Our results suggest that the sequencing of isolated chromosome arms can provide valuable information on the gene content of wheat, and that these assemblies can be applied for genome wide SNP discovery, the identification of candidate genes associated with genetically mapped traits and investigation of genome evolution in this important crop. This information is being applied within the Australian Centre for Functional Genomics to improve abiotic stress tolerance in wheat, supporting reliable crop production in Australia’s increasingly hostile environment. All data is available at http://wheatgenome.info/.