A portion of xylem (PO:0005352) tissue that is a distinct ring-like structure composed of tracheids (PO:0000301), that is part of a seed (PO:0009010) and surrounds the hilum (PO:0020063) and forms a groove in the surface of the pericarp (PO:0009084) immediately adjacent to the hilum. [ ISBN:0080280293 ]
术语信息
- PO_GIT:434
A portion of xylem (PO:0005352) tissue that is a distinct ring-like structure composed of tracheids (PO:0000301), that is part of a seed (PO:0009010) and surrounds the hilum (PO:0020063) and forms a groove in the surface of the pericarp (PO:0009084) immediately adjacent to the hilum.