The transverse section of canna root shows the following features under microscope.
(i) Epiblema:
It is the outer most layer containing a single layer of cells. Cells are without cuticle. Some of the cells produce unicellular root hairs.
(ii) Cortex:
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It is a broad zone of parenchyma cells with intercellular spaces found inner to epiblema. Some of the cells possess starch grains which appear as black spots. Large or small air spaces are seen in this region.
(iii) Endodermis:
It is the inner layer of cortex and consists of a simple layer of barrel shaped cells. Some thin walled rounded cells are also present corresponding to the protoxylem points.
(iv) Pericycle:
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It is a layer of compactly arranged thin walled parenchyma below the endodermis.
(v) Vascular bundles:
Vascular bundles are radial in nature. Xylem is polyarch, i.e., more than six patches of xylem are found alternating with equal patches of phloem. Vascular bundle is closed and exarch. Parenchymatous conjunctive tissue is present in between xylem and phloem patches.
(vi) Pith:
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It is the central zone made up of compactly arranged parenchymatous cells. Sometimes these cells are lignified.