Identification of Low Phytic Acid in a Maize Inbred Line and Primary Screening of Its Molecular Markers

Abstract

Reducing the content of phytic acid (PA, myo-inositol-1,2,3,4,5,6-hexakis phosphate) is important for improving the nutritional value of maize (Zea mays L.). The identification and application of low phytic acid (lpa) maize germplasm is an economical and effective approach in breeding program. In our previous study, Qi319 was identified as a low phytic acid inbred line. In this study, we found that the content of phytic acid phosphorus in Qi319 kernels is about one fourth of normal maize inbred lines based on quantitative analysis. The characterization of agronomic traits revealed that the germination rate of Qi319 was 75.5%, lower than that of normal inbred lines, however, Qi319 plants grew normally in the field. F2 population was generated by crossing between Qi319 and Lpa241, segregation was found for the content of phytic acid among F2 populations. The segregation ratio of 3:1 confirmed that the lpa trait was determined by a single recessive gene. We then identified two molecular markers (IDP7818 and IDP7635) located on the long arm of chromosome 2 that were co-segregated with low phytic acid loci. This result provides a fundamental basis for marker-assisted maize lpa selection process.