CHARACTERIZATION OF THE MYO-INOSITOL (3) PHOSPHATE SYNTHASE GENE (MIPS) AND MAPPING OF A LPA MUTANT IN SOYBEAN (GLYCINE MAX (L.) MERRILL).

Abstract

Low phytic acid (LPA) is a mutation causing phosphorus to be stored as unbound phosphorus in the seed. LPA mutants show a high inorganic phosphorus (HIP) phenotype. Previous studies had indicated that LPA might be linked to the myo-inositol (3) phosphate synthase (MIPS) gene; this research attempted to associate a soybean HIP mutant with the MIPS gene. The parental and the F2 genotypes were tested in four ways: 1) SNP detection using the LCR protocol; 2) polymorphism detection with PCR; 3) high inorganic phosphorus (HIP) phenotype detection; and 4) oil and protein concentration. The two parental genotypes could not be differentiated in the LCR study. A PCR-based polymorphism was heritable in the F2 genotypes. HIP assay indicated multiple genes control the LPA mutant. A polymorphism was associated to the HIP phenotype. The three types of HIP phenotypes were not statistically different in oil and protein concentrations allowing implementation into a breeding program.