Fig. 4From: Biosynthetic mechanisms of isoflavone accumulation affected by different growth patterns in Astragalus mongholicus productsStructural anatomy of A. mongholicus roots. P: Periderm; SP: Secondary phloem; PF: Phloem fiber; PP: Phloem parenchyma cells; PX: Primary xylem; V: Vessel; VR: Vascular ray; VC: Vascular cambium; and SX: Secondary xylem. The red circle indicates the gaps in the principal roots. The yellow box indicates an enlarged view of the principal rootBack to article page