Fine Points of Marker-Assisted Pyramiding of Anthocyanin Biosynthesis Regulatory Genes for the Creation of Black-Grained Bread Wheat (Triticum aestivum L.) Lines

Abstract

Enrichment of grains with anthocyanins is considered a feasible approach to improving the nutritional properties of bread wheat. Here, two black-grained substitution lines with either 4B or 4D chromosomes substituted by wheatgrass (Thinopyrum ponticum) 4Th were created via marker-assisted combining the anthocyanin biosynthesis regulatory genes Pp-1, Pp3 (Purple pericarp), and Ba1 (Blue aleurone) in the genetics background of cv. Saratovskaya 29. The black grains manifested the simultaneous accumulation of anthocyanins in aleurone, and the pericarp layers resulted in the highest total anthocyanin content (TAC), which amounted to approximately the sum of TACs of the purple and blue grains. The lines with substitution 4Th(4B) had long trichomes on the leaves, whereas the lines with substitution 4Th(4D) did not differ from parental cv. Saratovskaya 29. Despite the chromosome substitution having a positive effect on the main spike length, the other yield-related traits (grain weight per main spike, the spike number per plant, and the 1000-grain weight) were decreased in the lines with chromosome substitution. The developed lines together with the parental ones constitute a valuable model for comparative studies and genetic stock for breeding commercial wheat cultivars featuring high levels of anthocyanins in grains.