Abstract

Phytic acid (PA) is the most abundant form of phosphorus (P) in cereal grains. PA chelates mineral cations to form an indigestible salt and is thus regarded as an antinutritional agent and a contributor to water pollution. Grain with low phytic acid (lpa) genotypes could aid in mitigating this problem. In barley, more than 20 lpa mutant lines have been isolated, representing at least 6 different genetic loci. These mutants have significantly reduced levels of seed PA, which are largely replaced by inorganic P, a form readily digestable by animals. Use of lpa lines in breeding has proved a practical approach for improvement of phosphorus nutrition in barley. Efficient utilization of these loci in marker-assisted selection breeding programs requires identification of closely-linked, high-throughput molecular markers. Here we report development of flanking, PCR-based markers for 3 major lpa loci in barley: lpa1-1 (M422), lpa2-1 linked locus (M640), and a locus linked to the myo-inositol 1-phosphate synthase (MIPS) gene (M678). In addition, marker position accuracy in the MIPs region has been improved by detection and elimination of marker redundancy.

Key words:  Barley breeding, SSR marker, low phytic acid (lpa), grain nutrition.