Genome-wide Approaches to Identifying the Basis of Early Flowering in Epimutagenized Royal Flax

Early-flowering demethylated flax genotypes (RE1, 2 & 3) are being studied in a series of experiments to explore the genetic and epigenetic basis of traits, such as early flowering and early maturity, which will be useful in the breeding of flax adapted to the Canadian prairies. These experiments involve the use of genome-wide sequence data for the early-flowering (RE) lines and their progenitor line, Royal (RC) flax, in combination with field studies used to characterize northern adapted traits. We are currently focusing our efforts on four key areas: (1) Phenotyping three RIL (recombinant inbred line) populations derived from RC x RE crosses to characterize northern adapted traits in three separate environments, (2) a bulked QTL-seq study using two groups of RILs that show either consistently early flowering or consistently late flowering to identify loci associated with the early-flowering phenotype, (3) an RNA-seq experiment to identify differential gene expression and differences in the timing of the expression of key flowering genes between RC and RE lines, and (4) bisulphite sequencing to identify differences in methylation patterns that may correspond with differential gene expression. The findings of these studies will contribute to deciphering the flowering pathways utilized by flax and provide data necessary to identify the heritable changes resulting in the early-flowering phenotype.