Which are the plant tissues that form the plant roots?

The roots have a central portion known as medulla made of vascular tissue (inner xylem and outer phloem). The medulla is surrounded by the medullary parenchyma and delimited by pericycle, a meristem that originates the secondary roots (ramifications). Externally to the medulla lies the cortical portion produced of endodermis (that surrounds the pericycle) and cortical parenchyma. The covering of the roots is epidermis (with root hairs) later substituted by suberized (corky) periderm.

Image Diversity: root structure root hairs