Population Epigenomic Diversity Across the Watkins Bread Wheat Landrace Cultivar Collection

There is a high level of genetic diversity in the A. E. Watkins bread wheat landrace collection. Here, we analyze DNA methylation, an important mechanism of epigenetic gene expression control that can be passed between generations, across a core set of the Watkins collection. This core set includes 105 lines and captures the majority of the diversity in the Watkins collection. Using sodium bisulfite treatment and targeted gene enrichment we can survey genome-wide methylation across the three sub-genomes of allohexaploid wheat and effectively assess the extent of epigenetic variation across a population. Furthermore, this analysis will be combined with gene expression analyses.

We have observed that methylation is a standalone source of variation in the absence of genetic variation, however, it is clear that if two wheat accessions show more closely related genotypes then their methylomes are more likely to be related. In support of our previous hypotheses it is also apparent that tri-genome methylation is more conserved between accessions than genome specific methylation.