An optimized high‐throughput colorimetric assay for phytic acid quantification

Abstract Phytic acid (PA) is the primary storage form of phosphorus in seeds and is considered an anti‐nutritional factor because of its ability to chelate essential minerals, thereby reducing their bioavailability. However, identifying low‐PA mutants in large populations requires a cost‐effective, accurate, and high‐throughput screening method. A previously reported colorimetric method for quantifying PA in soybean ( Glycine max (L.) Merr.). However, the throughput of that method is relatively low. In this study, we modified several key steps of the protocol to improve its throughput. The accuracy of the modified protocol was validated by comparing it with the original method and a commercially available PA quantification kit. The new high‐throughput protocol showed high reproducibility and successfully distinguished existing low‐PA mutants from their wild‐type parent. The protocol was then used to screen a diversity panel of 202 pea accessions ( Pisum sativum L.), which revealed a wide genetic variation in PA content. We identified two novel low‐PA accessions, JI0383 and JI3253, with 69% and 48% reductions in PA, respectively, compared to the population mean values. This cost‐effective method is expected to help researchers and breeders accelerate the development of low‐PA crops to meet the current demand for high‐quality plant‐based foods.