QTL Analysis For Seed Metabolites In Brachypodium distachyon

Agriculturally and economically important traits of crops, such as grain yield and quality, are influenced by metabolic performance. To investigate genetic basis of metabolic phenotypes, a metabolome-QTL (mQTL) analysis was performed for seeds of Brachypodium distachyon. The combinatorial use of metabolome analytical platforms and genetic populations allows us to figure out novel insights into genetic regulatory mechanisms underlying metabolic phenotype variation. To identify differentially accumulated metabolites between parental lines, Bd21 and Bd3-1, we performed widely-targeted metabolome analysis for known 517 compounds. As the result, we chose 28 target metabolites that are stably detectable and showed significantly differences in abundance between these two lines. Then, 164 recombinant inbred lines (RILs) derived from a cross between Bd21 and Bd3-1, which have been genotyped with 551 single nucleotide polymorphism (SNP) markers, were used for a mQTL analysis. To detect and map mQTLs, the genotyping data and the metabolic phenotype data on chosen 28 compounds were calculated by using  the R/qtl software. We found 6 metabolites which showed QTL peaks allocated on the Brachypodium chromosomes with significantly high logarithm of odds (LOD) scores. For example, each of these compounds likely related to flavonoid biosynthesis, anthocyanin biosynthesis and vitamin B6 biosynthesis. Non-targeted metabolome analysis of seeds of B. distachyon will also be discussed in our talk.