Stability of the Metabolite Signature Resulting from the MIPS1 Mutation in Low Phytic Acid Soybean (Glycine max L. Merr.) Mutants upon Cross-Breeding

The low phytic acid (lpa) soybean (Glycine max L. Merr.) mutant Gm-lpa-TW-1-M, resulting from a 2 bp deletion in GmMIPSI, was crossed with a commercial cultivar. F3 and F5 progenies were subjected to nontargeted GC-based metabolite profiling, allowing analysis of a broad array of low molecular weight constituents. In the homozygous 1pa mutant progenies the intended phytic acid reduction was accompanied by remarkable metabolic changes of nutritionally relevant constituents such as reduced contents of raffinose oligosaccharides and galactosyl cyclitols as well as increased concentrations in sucrose and various free amino acids. The mutation-induced metabolite signature was nearly unaffected by the cross-breeding and consistently expressed over generations and in different growing seasons. Therefore, not only the primary MIPSI 1pa mutant but also its progenies might be valuable genetic resources for commercial breeding programs to produce soybean seeds stably exhibiting improved phytate-related and nutritional properties.