vascular bundle

Also found in: Dictionary, Thesaurus, Medical, Wikipedia.

vascular bundle,

in botany, a strand of conducting tissue extending lengthwise through the stems and roots of higher plants, including the ferns, fern allies, gymnosperms, and angiosperms. The vascular bundle consists of xylem, which conducts water and dissolved mineral substances from the soil to the leaves, and phloem, which conducts dissolved foods, especially sugars, from the leaves to the storage tissues of the stem and root. The structure of vascular bundles varies among the different plant groups. See woodwood,
botanically, the xylem tissue that forms the bulk of the stem of a woody plant. Xylem conducts sap upward from the roots to the leaves, stores food in the form of complex carbohydrates, and provides support; it is made up of various types of cells specialized for each of
..... Click the link for more information.
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Vascular Bundle


in plants, the aggregate of elements of the vascular tissue. The vascular bundle appears in the sprout from the apical meristem or, more precisely, from the procam-bium. It comprises the xylem, the phloem, mechanical tissues, and cells of the living parenchyma. A vascular bundle may be complete or incomplete; that is, in the latter case it may consist of only phloem or only xylem. Dicotyledons are marked by open vascular bundles; in other words, part of the procambium is not differentiated into vascular tissue and remains in the form of cambium. Monocotyledons have closed bundles, without a cambium.

In a collateral bundle, the phloem occurs along one side of the stem, outside the xylem. The presence of phloem along both sides of the xylem makes the bundle bicollateral. A concentric bundle is one that is either amphibasal, with the xylem surrounding the phloem, or amphicribral, with the phloem surrounding the xylem. The structure of a vascular bundle may vary at different points along the stem.

In roots the vascular bundles form radial structures consisting of individual alternating sections of xylem and phloem along the radii of the vascular cylinder.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

vascular bundle

[′vas·kyə·lər ′bənd·əl]
A strandlike part of the plant vascular system containing xylem and phloem.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Abbreviations: proportion Of the adaxial epidermis (ADE%); proportion of abaxial epidermis (ABE%); proportion of chlorophyll parenchyma (PAR%); proportion of the sum of total phloem in the leaf (PHT%); proportion of the phloem in one vascular bundle (PHVB%); proportion of the bundle sheath in the vascular bundle (BS%); proportion of the vascular bundles in the leaf (VB%); proportion of the sum of total xylem in the leaf (XLT%); proportion of the phloem in one vascular bundle (XLVB%); proportion of the sum of total fibers in the leaf (FBT%), proportion of the fibers in one vascular bundle (FBFV%).
a- Starch occurring near the larval chamber; b- proteins around the larval chamber; c- reducing sugar near the larval chamber; d- lipid compound detected in secretory cavity; e, f, g- oxidative stress occurs predominantly in the epidermis (e), secretory cavities (f) and in the vascular bundles near the larval chamber (g).
In this present study, however, the lower basic density in the nodal area was presumably attributed to its bigger bulk with less vascular bundle in comparison with the internode.
Collateral vascular bundles of second order (Figure 3i) occurred periodically in the mesophyll of the leaf blade, interspersed with smaller frequency by first-order bundles (Figure 3g).
Large cortical cell area, epidermal thickness, midrib thickness, vascular bundle area, metaxylem area and spongy cell area in leaves increased in all Rosa species as contamination increased in irrigation waters and R.
On the other hand, after observing the impact of the UV frequency on the material removal rate, as shown in Figure 3, we clearly found that with an increase in vibration frequency, the material removal rate increased because the UV effect made the diamond slurry go through the vascular bundle of bamboo charcoal more quickly, and further enhancing the removal rate of machining materials.
Digitaria insularisshowed differences in stomata, vascular bundle, parenchyma, xylem/ phloem relation and trichomes that caninfluence the different glyphosate efficacy between biotypes.The herbicide resistance caused by differential absorption is complex and still need further studies.
This scale is then one of few armoured scale species that are capable of piercing lignified plant cells walls like fibers and the xylem vessels in vascular bundles. Leaf vascular bundle penetration by SB has been previously reported in only 2 species of scales (Heriot 1934; Washington & Walker 1990).
According to the early mesoscopic research about bamboo by the authors in this paper, bamboo is a kind of composite composed of a vascular bundle and matrix (thin-walled cells).
Angiography is mainly done in cases where the injury is in close proximity to the vascular bundle (proximity wounds) and there are no obvious signs of vascular injury25 or when exact localization of vascular injury are required.

Full browser ?