Genomic Diversity and Climate Adaptation in Brachypodium

Abstract

The Brachypodium genus contains the model grasses B. distachyon, B. stacei and B. hybridum, that are useful for molecular and physiological studies relevant to grain, pasture and bioenergy crops, as well as ecology. In this chapter we discuss the natural variation in climate/geography, genotypic and phenotypic diversity that exists within these species. We describe utilisation of this diversity via two methods, Genome Wide Association Studies and Landscape Genomics, to examine the interaction between specific genetic variants, phenotype, and environment. The aim is to identify adaptive loci that control specific traits in specific environments and understand the contribution of background polygenetic variation shaped by demographic processes. With recent developments in high throughput phenotyping, cheaper genotyping by sequencing and higher spatial/temporal resolution of climate data, these approaches can exploit the diversity of the Brachypodium. Experiments using this toolkit will reveal alleles, genes and pathways underlying agriculturally important and environmentally sensitive traits for use in grass breeding.