Origin of black glume color in Triticum aestivum lines with introgressions from wheat wild relatives

Abstract

Dark glume color in Triticinae is a much-studied morphological character. However, pigments that cause the color, the molecular basis of their biosynthesis, and mechanisms of its regulation are still unknown. Dark glume is a common trait in Triticum aestivum lines with alien introgressions. To elucidate the molecular basis of this character, we analyzed the total phenolic content (TPC) in the dark glumed introgression lines (ILs) and their parents. TPC in the dark ILs was found to be higher than their parents and light-glumed lines. All the genotypes were screened for the expression of eight genes encoding the flavonoid biosynthesis pathway enzymes. Expression of three flavonoid genes in the pathway was changed in the introgression lines as compared with their parents. The expression of F3′H and FNS was absent in the lines with introgressions from Aegilops spp. The expression of three genes, F3′H, FLS, and FNS, was found to be altered in the light glumed lines with introgressions from Amblyopyrum muticum. No expression of F3′H was detected in the T. aestivum/Am. muticum lines with light and dark plants, and the other genes of the pathway were found to be expressed at the parental levels. No correlation between the expression profiles and the phenotype was found in the T. aestivum/Am. muticum lines indicating other undetected changes in these lines.