Research Progress on Plant Seed Phytate

Phosphorus (P) is an essential macro-element for higher plant growth and develop-ment. Phytate is the storage form of P in seeds, and plays vitally important roles in P sensing and homeostasis during seed development. Phytate is hydrolyzed by phytases and releases P, mineral nutrients, and myo-inositol for seedling growth during seed germination. This paper reviewed advances in studies, including the biosynthesis pathway of phytic acid, heredity of phytate in seeds, and the breeding of low phytic acid crops. Firstly, glucose 6-phosphate and inositol (Ins) serve as the initial substrates for two pathways to synthesize phytic acid: the lipid-dependent and lipid-independent pathways. Several key genes and enzymes involved in the biosynthesis and transport of phytic acid have been identified, including genes encoding myo-inositol-3-P₁ synthase (MIPS), MIK, IPK, and a multi-drug resistance-associated protein (MRP) ATP-binding cassette transporter. Secondly, some genetic loci for seed phytate content have been detected in rice, Brassica rapa, common bean, mung bean and chickpea, using the genetic mapping population and/or genome-wide association panel, respectively. Thirdly, identification of valuable low phytic acid mutants is important for the breeding of low-phytate crops. Once breeding low-phytate crops is a target, scientists can focus on how to reduce the negative effects accompanied by low phytic acid in crops.