Responsible for the provision of inositol required for synthesis of phosphatidylinositol and polyphosphoinositides. a myo-inositol phosphate + H2O = myo-inositol + phosphate Polyol metabolism; myo-inositol biosynthesis; myo-inositol from D-glucose 6-phosphate: step 2/2. Expressed in the shoot apex, roots, stems, leaves, flowers and young and mature green fruits. Up-regulated by light and down-regulated by Li(+). Belongs to the inositol monophosphatase superfamily.