pericycle

American  

[per-uh-sahy-kuhl] / ˈpɛr əˌsaɪ kəl /

noun

Botany.

1. the outermost cell layer of the stele in a plant, frequently becoming a multilayered zone.

---

pericycle British  

/ -ˈsɪk-, ˌpɛrɪˈsaɪklɪk, ˈpɛrɪˌsaɪkəl /

noun

1. a layer of plant tissue beneath the endodermis: surrounds the conducting tissue in roots and certain stems

---

pericycle Scientific  

/ pĕr′ĭ-sī′kəl /

1. A layer of nonvascular tissue that surrounds the vascular tissues in the roots of plants and is in turn surrounded by the endodermis. New lateral roots begin growth from the pericycle.

---

Other Word Forms

• pericyclic adjective

Etymology

Origin of pericycle

From the Greek word períkyklos, dating back to 1890–95. See peri-, cycle

Example Sentences

The irritated pericycle and cortex then grow and form nodules of soft juicy root-tissue at which the insect continues to suck.

From Project Gutenberg

After the cambium has been active for some time producing secondary xylem and phloem, the latter consisting of sieve-tubes, phloem-parenchyma and frequently thick-walled fibres, a second cambium is developed in the pericycle; this produces a second vascular zone, which is in turn followed by a third cambium, and so on, until several hollow cylinders are developed.

From Project Gutenberg

The root is diarch in structure, but additional protoxylem-strands may be present at the base of the main root; the pericycle consists of several layers of cells.

From Project Gutenberg

The endodermis in Pinus, Picea and many other genera is usually a well-defined layer of cells enclosing the vascular bundles, and separated from them by a tissue consisting in part of ordinary parenchyma and to some extent of isodiametric tracheids; but this tissue, usually spoken of as the pericycle, is in direct continuity with other stem-tissues as well as the pericycle.

From Project Gutenberg

It has been suggested that transfusion-tracheids represent, in part at least, the centripetal xylem, which forms a distinctive feature of cycadean leaf-bundles; these short tracheids form conspicuous groups laterally attached to the veins in Cunninghamia, abundantly represented in a similar position in the leaves of Sequoia, and scattered through the so-called pericycle in Pinus, Picea, &c.

From Project Gutenberg